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Journal Cover Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy
  [SJR: 0.717]   [H-I: 80]   [17 followers]  Follow
    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 1386-1425
   Published by Elsevier Homepage  [3039 journals]
  • Antimycobacterial, antimicrobial activity, experimental (FT-IR, FT-Raman,
           NMR, UV–Vis, DSC) and DFT (transition state, chemical reactivity, NBO,
           NLO)
    • Authors: Poonam Rawat; R.N. Singh; Alok Ranjan; Sartaj Ahmad; Rajat Saxena
      Pages: 1 - 10
      Abstract: Publication date: 15 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 179
      Author(s): Poonam Rawat, R.N. Singh, Alok Ranjan, Sartaj Ahmad, Rajat Saxena
      As part of a study of pyrrole hydrazone, we have investigated quantum chemical calculations, molecular geometry, relative energy, vibrational properties and antimycobacterial/antimicrobial activity of pyrrole-2-carboxaldehyde isonicotinyl hydrazone (PCINH), by applying the density functional theory (DFT) and Hartree Fock (HF). Good reproduction of experimental values is obtained and with small percentage error in majority of the cases in comparison to theoretical result (DFT). The experimental FT-IR and Raman wavenumbers were compared with the respective theoretical values obtained from DFT calculations and found to agree well. In crystal structure studies the hydrated PCINH (syn-syn conformer) shows different conformation than from anhydrous form (syn-anti conformer). The rotational barrier between syn-syn and syn-anti conformers of PCINH is 12.7kcal/mol in the gas phase. In this work, use of FT-IR, FT-Raman, 1H NMR, 13C NMR and UV–Vis spectroscopies has been made for full characterization of PCINH. A detailed interpretation of the vibrational spectrum was carried out with the aid of normal coordinate analysis using single scaling factor. Our results support the hydrogen bonding pattern proposed by reported crystalline structure. The calculated nature of electronic transitions within molecule found to be π→π*. The electronic descriptors study indicates that PCINH can be used as robust synthon for synthesis of new heterocyclic compounds. The first static hyperpolarizability (β0) of PCINH is calculated as 33.89×10−30 esu, (gas phase); 68.79×10−30 (CHCl3), esu; 76.76×10−30 esu (CH2Cl2), 85.16×10−30 esu (DMSO). The solvent induced effects on the first static hyperpolarizability were studied and found to increase as dielectric constants of the solvents increases. Investigated molecule shows better NLO value than Para nitroaniline (PNA). The compound PCINH shows good antifungal and antibacterial activity against Aspergillus niger and gram-positive bacteria Bacillus subtilis, respectively. The compound also shows good antituberculosis activity against Mycobacterium tuberculosis H37Rv using the microplate alamar blue assay (MABA).
      Graphical abstract image

      PubDate: 2017-02-18T11:59:56Z
      DOI: 10.1016/j.saa.2017.02.021
      Issue No: Vol. 179 (2017)
       
  • A novel sensor for determination of naproxen based on change in localized
           surface plasmon peak of functionalized gold nanoparticles
    • Authors: Javad Khodaveisi; Ali Mohammad Haji Shabani; Shayessteh Dadfarnia; Dariush Saberi
      Pages: 11 - 16
      Abstract: Publication date: 15 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 179
      Author(s): Javad Khodaveisi, Ali Mohammad Haji Shabani, Shayessteh Dadfarnia, Dariush Saberi
      A highly selective and sensitive colorimetric sensor for the determination of naproxen (NAP) based on the aggregation of the thiolated β-cyclodextrin (Tβ-CD) functionalized gold nanoparticles (Tβ-CD-Au NPs) in the presence of NAP and Zn2+ is described. The hydrophobic end of NAP interacts with the immobilized Tβ-CD on the Au NPs and forms the complex of Tβ-CD:NAP while the Zn2+ ions form a 1:2 complex of (NAP)2Zn with the carboxyl groups of NAP resulting in the aggregation of functionalized gold nanoparticles. As a result of aggregation, the localized surface plasmon resonance (LSPR) band of functionalized gold nanoparticles around 520nm decreases and a new red shifted band at 650nm appears which increases gradually as the function of NAP concentration. The calibration graph derived from the intensity ratios of absorbance at 650nm to 520nm was linear in the concentration range of 4–180μgL−1of NAP. At the optimum conditions, the limit of detection (LOD) and quantification (LOQ) were found to be 0.6 and 2.1μgL−1, respectively and the relative standard deviation at 20μgL−1of NAP (n=5) was 2.5%. The selectivity and applicability of the method was verified through analyzes of the synthetic samples containing the major interference compounds reported in literature as well as tablets, wastewater and urine samples. The accuracy of the method was evaluated by recovery experiments and analysis of pharmaceutical tablets.
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      PubDate: 2017-02-18T11:59:56Z
      DOI: 10.1016/j.saa.2017.02.008
      Issue No: Vol. 179 (2017)
       
  • Thermostability of photosystem I trimers and monomers from the
           cyanobacterium Thermosynechococcus elongatus
    • Authors: Vladimir V. Shubin; Irina V. Terekhova; Yulia V. Bolychevtseva; Eithar El-Mohsnawy; Matthias Rögner; Werner Mäntele; Marta J. Kopczak; Enela Džafić
      Pages: 17 - 22
      Abstract: Publication date: 15 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 179
      Author(s): Vladimir V. Shubin, Irina V. Terekhova, Yulia V. Bolychevtseva, Eithar El-Mohsnawy, Matthias Rögner, Werner Mäntele, Marta J. Kopczak, Enela Džafić
      The performance of solar energy conversion into alternative energy sources in artificial systems highly depends on the thermostability of photosystem I (PSI) complexes Terasaki et al. (2007), Iwuchukwu et al. (2010), Kothe et al. (2013) . To assess the thermostability of PSI complexes from the thermophilic cyanobacterium Thermosynechococcus elongatus heating induced perturbations on the level of secondary structure of the proteins were studied. Changes were monitored by Fourier transform infrared (FT-IR) spectra in the mid-IR region upon slow heating (1°C per minute) of samples in D2O phosphate buffer (pD 7.4) from 20°C to 100°C. These spectra showed distinct changes in the Amide I region of PSI complexes as a function of the rising temperature. Absorbance at the Amide I maximum of PSI monomers (centered around 1653cm−1), gradually dropped in two temperature intervals, i.e. 60–75 and 80–90°C. In contrast, absorbance at the Amide I maximum of PSI trimers (around 1656cm−1) dropped only in one temperature interval 80–95°C. The thermal profile of the spectral shift of α-helices bands in the region 1656–1642cm−1 confirms the same two temperature intervals for PSI monomers and only one interval for trimers. Apparently, the observed absorbance changes at the Amide I maximum during heating of PSI monomers and trimers are caused by deformation and unfolding of α-helices. The absence of absorbance changes in the interval of 20–65°C in PSI trimers is probably caused by a greater stability of protein secondary structure as compared to that in monomers. Upon heating above 80°C a large part of α-helices both in trimers and monomers converts to unordered and aggregated structures. Spectral changes of PSI trimers and monomers heated up to 100°C are irreversible due to protein denaturation and non-specific aggregation of complexes leading to new absorption bands at 1618–1620cm−1. We propose that monomers shield the denaturation sensitive sides at the monomer/monomer interface within a trimer, making the oligomeric structure more stable against thermal stress.
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      PubDate: 2017-02-18T11:59:56Z
      DOI: 10.1016/j.saa.2017.02.010
      Issue No: Vol. 179 (2017)
       
  • Extraction, preparation and application of pigments from Cordyline
           fruticosa and Hylocereus polyrhizus as sensitizers for dye-sensitized
           solar cells
    • Authors: Mahmoud A.M. Al-Alwani; Norasikin A. Ludin; Abu Bakar Mohamad; Abd. Amir H. Kadhum; Kamaruzzaman Sopian
      Pages: 23 - 31
      Abstract: Publication date: 15 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 179
      Author(s): Mahmoud A.M. Al-Alwani, Norasikin A. Ludin, Abu Bakar Mohamad, Abd. Amir H. Kadhum, Kamaruzzaman Sopian
      Current study employs mixture of chlorophyll-anthocyanin dye extracted from leaves of Cordyline fruticosa as new sensitizers for dye-sensitized solar cell (DSSCs), as well as betalains dye obtained from fruit of Hylocereus polyrhizus. Among ten pigments solvents, the ethanol and methanol extracts revealed higher absorption spectra of pigments extracted from C. fruticosa and H. polyrhizus respectively. A major effect of temperature increase was studied to increase the extraction yield. The results indicated that extraction temperature between 70 and 80°C exhibited a high dye concentration of each plant than other temperatures. The optimal temperature was around 80°C and there was a sharp decrease of dye concentration at temperatures higher than this temperature. According to experimental results, the conversion efficiency of DSSC fabricated by mixture of chlorophyll and anthocyanin dyes from C. fruticosa leaves is 0.5% with short-circuit current (Isc) of 1.3mA/cm−2 , open-circuit voltage (Voc) of 0.62V and fill factor (FF) of 60.16%. The higher photoelectric conversion efficiency of the DSSC prepared from the extract of H. polyrhizus was 0.16%, with Voc of 0.5V, Isc of 0.4mA/cm−2 and FF of 79.16%. The DSSC based betalain dye extracted from fruit of H. polyrhizus shows higher maximum IPCE of 44% than that of the DSSCs sensitized with mixed chlorophyll-anthocyanin dye from C. fruticosa (42%).
      Graphical abstract image

      PubDate: 2017-02-18T11:59:56Z
      DOI: 10.1016/j.saa.2017.02.026
      Issue No: Vol. 179 (2017)
       
  • Selective detection of Cu2+ and Co2+ in aqueous media: Asymmetric
           chemosensors, crystal structure and spectroscopic studies
    • Authors: Samira Gholizadeh Dogaheh; Hamid Khanmohammadi; E. Carolina Sañudo
      Pages: 32 - 41
      Abstract: Publication date: 15 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 179
      Author(s): Samira Gholizadeh Dogaheh, Hamid Khanmohammadi, E. Carolina Sañudo
      Two new azo-azomethine receptors, H2L1 and H2L2, containing hydrazine, naphthalene and different electron withdrawing groups, Cl and NO2, have been designed and synthesized for qualitative and quantitative detection of Cu2+ and Co2+ in aqueous media. The crystal structure of H2L1is reported. The H2L1was used as a chemosensor for selective detection of trace amount of Cu2+ in aqueous media. H2L2 was also applied to naked-eye distinction of Cu2+ and Co2+ from other transition metal ions in aqueous media. Detection limit of Cu2+ is 1.13μM and 1.26μM, in water, for H2L1 and H2L2, respectively, which are lower than the World Health Organization (WHO) recommended level. The binuclear Cu2+ and Co2+ complexes of the receptors have been also prepared and characterized using spectroscopic methods and MALDI-TOF mass analysis. Furthermore, the binding stoichiometry between the receptors upon the addition Cu2+ and Co2+ has been investigated using Job's plot. Moreover, the fluorescence emission spectra of the receptors and their metal complexes are also reported.
      Graphical abstract image

      PubDate: 2017-02-18T11:59:56Z
      DOI: 10.1016/j.saa.2017.02.017
      Issue No: Vol. 179 (2017)
       
  • Intense 2.7μm emission in Er3+ doped zinc fluoride glass
    • Authors: Feifei Huang; Yanyan Guo; Ying Tian; Shiqing Xu; Junjie Zhang
      Pages: 42 - 45
      Abstract: Publication date: 15 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 179
      Author(s): Feifei Huang, Yanyan Guo, Ying Tian, Shiqing Xu, Junjie Zhang
      A novel erbium ion doped zinc fluoride glass was prepared. 2.7μm emission and transmittance properties together with thermal ability were investigated. An enhanced 2.7μm emission was observed by introducing ZnF2 in the ZrF4-based fluoride glass. Meanwhile, the J-O parameters and branching ratios (β) of Er3+-doped zinc fluoride glass were calculated and analyzed. The present Er3+-doped zinc fluoride glass with large emission cross-section (0.92×10−20 cm2) and long decay lifetime (2.05ms) at 2.7μm indicates that it have very promising applications for solid state lasers around 3μm.
      Graphical abstract image

      PubDate: 2017-02-18T11:59:56Z
      DOI: 10.1016/j.saa.2017.02.020
      Issue No: Vol. 179 (2017)
       
  • Chiral-aminoquinoline-based fluorescent pH probe with large stokes shift
           for bioimaging
    • Authors: Yong-Sheng Xie; Xin-Ling Zhang; Kun Xie; Yanmei Zhao; Huan Wu; Jidong Yang
      Pages: 51 - 57
      Abstract: Publication date: 15 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 179
      Author(s): Yong-Sheng Xie, Xin-Ling Zhang, Kun Xie, Yanmei Zhao, Huan Wu, Jidong Yang
      The aminoquinoline derivatives, (R)- and (S)-2-phenyl-2-(quinolin-6-ylamino)ethan-1-ol ( R-PEO and S-PEO), were synthesized by a tandem one-pot three-step CN coupling method where Smiles rearrangement was the key procedure. The selected compound R-PEO showed a significant fluorescence enhancement with a turn-on ratio over 98-fold and enabled the real time determination of proton concentration in acidic solution. The fluorescence intensity of R-PEO exhibited strong pH-dependent performance with a large Stokes shift (115nm) and responded linearly to minor pH change within the range of 3.8–6.0. With the help of 1H NMR spectrum, we also confirmed the protonation of the quinoline unit should be the proposed reaction. Compared with the conjugated acid of N-hexylquinolin-6-amine (NQA), the conjugated acid of R-PEO shows significant planar intramolecular charge transfer (PICT) character. Furthermore, biological imaging proved that R-PEO probe can be used to monitor the pH change of S. cerevisiae in vivo.
      Graphical abstract image

      PubDate: 2017-02-18T11:59:56Z
      DOI: 10.1016/j.saa.2017.02.025
      Issue No: Vol. 179 (2017)
       
  • Photo-degradation of basic green 1 and basic red 46 dyes in their binary
           solution by La2O3-Al2O3nanocomposite using first-order derivative spectra
           and experimental design methodology
    • Authors: Bahareh Fahimirad; Alireza Asghari; Maryam Rajabi
      Pages: 58 - 65
      Abstract: Publication date: 15 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 179
      Author(s): Bahareh Fahimirad, Alireza Asghari, Maryam Rajabi
      In this work, the lanthanum oxide-aluminum oxide (La2O3-Al2O3) nanocomposite is introduced as an efficient photocatalyst for the photo-degradation of the dyes basic green 1 (BG1) and basic red 46 (BR46) in their binary aqueous solution under the UV light irradiation. The properties of this catalyst are determined by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Brunauer-Emmett-Teller (BET), and UV–visible spectrophotometry. The first-order derivative spectra are used for the simultaneous analysis of the dyes in their binary solution. The screening investigations indicate that five parameters including the catalyst dosage, concentration of the dyes, irradiation time, and solution pH have significant effects on the photo-degradation of the dyes. The effects of these variables together with their interactions in the photo-degradation of the dyes are studied using the Box-Behnken design (BBD). Under the optimum experimental conditions, obtained via the desirability function, the photo-catalytic activities of La2O3-Al2O3 and pure Al2O3 are also investigated. The results obtained show an enhancement in the photo-catalytic activity when La2O3 nanoparticles are loaded on the surface of Al2O3 nanoparticles.
      Graphical abstract image

      PubDate: 2017-02-18T11:59:56Z
      DOI: 10.1016/j.saa.2017.02.022
      Issue No: Vol. 179 (2017)
       
  • Green synthesis, characterization and catalytic activity of silver
           nanoparticles using Cassia auriculata flower extract separated fraction
    • Authors: Karuppiah Muthu; Sethuraman Priya
      Pages: 66 - 72
      Abstract: Publication date: 15 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 179
      Author(s): Karuppiah Muthu, Sethuraman Priya
      Cassia auriculata L., the flower aqueous extract was fractionated by separating funnel using n-hexane (A1), chloroform (A2), ethyl acetate (A3) and triple distilled water (A4). The A4 fraction was concentrated and determined the presence of preliminary phytochemicals such as tannins, flavonoids, glycosides, carbohydrates and polyphenolic compounds. These phytochemical compounds acted as reducing as well as a stabilizing agent in the green synthesis of Ag NPs from aqueous silver ions. Initially, the colour change and UV–vis absorbance surface Plasmon resonance strong, wide band located at 435nm has confirmed the synthesis of Ag NPs. The X-ray diffraction (XRD) pattern of Ag NPs shows a face-centered cubic crystal structure. The observed values were calculated by Debye-Scherrer equation to theoretical confirms the particle size of 18nm. The surface morphology of Ag NPs was viewed by HRTEM, the particles are spherical and triangle shapes with sizes from 10 to 35nm. Further, the Ag NPs was effective catalytic activity in the reduction of highly environmental polluted organic compounds of 4-nitrophenol and methyl orange. The green synthesis of Ag NPs seems to eco-friendly, cost-effective, conventional one spot synthesis and greater performance of catalytic degradation of environmentally polluted organic dyes.
      Graphical abstract image

      PubDate: 2017-02-18T11:59:56Z
      DOI: 10.1016/j.saa.2017.02.024
      Issue No: Vol. 179 (2017)
       
  • Corrigendum to “Laser-induced optical breakdown spectroscopy of polymer
           materials based on evaluation of molecular emission bands” [Spectrochim.
           Acta A Mol. Biomol. Spectrosc. 174 (2017) 331–338]
    • Authors: Stefan Trautner; Juraj Jasik; Christian G. Parigger; Johannes D. Pedarnig; Wolfgang Spendelhofer; Johannes Lackner; Pavel Veis; Johannes Heitz
      First page: 73
      Abstract: Publication date: 15 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 179
      Author(s): Stefan Trautner, Juraj Jasik, Christian G. Parigger, Johannes D. Pedarnig, Wolfgang Spendelhofer, Johannes Lackner, Pavel Veis, Johannes Heitz


      PubDate: 2017-02-18T11:59:56Z
      DOI: 10.1016/j.saa.2017.02.016
      Issue No: Vol. 179 (2017)
       
  • Microwave dielectric relaxation spectroscopy study of propylene
           glycol/ethanol binary mixtures: Temperature dependence
    • Authors: T. Vishwam; Suriya Shihab; V.R K. Murthy; Ha Sie Tiong; S. Sreehari Sastry
      Pages: 74 - 82
      Abstract: Publication date: 15 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 179
      Author(s): T. Vishwam, Suriya Shihab, V.R K. Murthy, Ha Sie Tiong, S. Sreehari Sastry
      Complex dielectric permittivity measurements of propylene glycol (PG) in ethanol at various mole fractions were measured by using open-ended coaxial probe technique at different temperatures in the frequency range 0.02<ν/GHz<20. The dipole moment (μ), excess dipole moment (Δμ),excess permittivity (εE), excess inverse relaxation time(1/τ)E, Bruggeman parameter (f B ), excess Helmholtz energy (ΔF E ) are determined using experimental data. From the minimum energy based geometry optimization, dipole moments of individual monomers of propylene glycol and ethanol and their binary system have been evaluated theoretically at gaseous state as well as alcoholic medium by using PCM and IEFPCM solvation models from the Hatree-Fock (HF) and Density Functional Theory (DFT-B3LYP) methods with 6-311G* and 6-311G** basis sets. The obtained results have been interpreted in terms of the short and long range ordering of the dipoles, Kirkwood correlation factor (geff), thermodynamic parameters, mean molecular polarizability (αM) and interaction in the mixture through hydrogen bonding.
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      PubDate: 2017-02-18T11:59:56Z
      DOI: 10.1016/j.saa.2017.02.023
      Issue No: Vol. 179 (2017)
       
  • A chemiluminescence biosensor based on the adsorption recognition function
           between Fe3O4@SiO2@GO polymers and DNA for ultrasensitive detection of DNA
           
    • Authors: Yuanling Sun; Jianbo Li; Yanhui Wang; Chaofan Ding; Yanna Lin; Weiyan Sun; Chuannan Luo
      Pages: 1 - 7
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Yuanling Sun, Jianbo Li, Yanhui Wang, Chaofan Ding, Yanna Lin, Weiyan Sun, Chuannan Luo
      In this work, a chemiluminescence (CL) biosensor was prepared for ultrasensitive determination of deoxyribonucleic acid (DNA) based on the adsorption recognition function between core-shell Fe3O4@SiO2 - graphene oxide (Fe3O4@SiO2@GO) polymers and DNA. The Fe3O4@SiO2@GO polymers were composed by GO and magnetite nanoparticles. And the core-shell polymers were confirmed by Scanning Electron Microscope (SEM), X-Ray Powder Diffraction (XRD) and Fourier Transform Infrared (FTIR). Then Fe3O4@SiO2@GO was modified by DNA. Based on the principle of complementary base, Fe3O4@SiO2@GO-DNA was introduced to the CL system and the selectivity, sensitivity of DNA detection was significantly improved. The adsorption properties of Fe3O4@SiO2@GO to DNA were researched through the adsorption equilibrium, adsorption kinetic and thermodynamics. Under optimized CL conditions, DNA could be assayed with the linear concentration range of 5.0×10−12–2.5×10−11 mol/L. The detection limit was 1.7×10−12 mol/L (3δ) and the relative standard deviation (RSD) was 3.1%. The biosensor was finally used for the determination of DNA in laboratory samples and recoveries ranged from 99% to 103%. The satisfactory results revealed the potential application of Fe3O4@SiO2@GO-DNA-CL biosensor in the diagnosis and the treatment of human genetic diseases.
      Graphical abstract image

      PubDate: 2017-02-05T09:37:21Z
      DOI: 10.1016/j.saa.2017.01.057
      Issue No: Vol. 178 (2017)
       
  • Spectrophotometric and electrochemical study for metal ion binding of
           azocalix[4]arene bearing p-ethylester group
    • Authors: Tae Hyun Kim
      Pages: 8 - 13
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Tae Hyun Kim
      The complexation behavior of diazophenylcalix[4]arene bearing para-ethylester group (p-EAC) for alkali, alkaline earth, various heavy and transition metal ions (Li+, Na+, K+, Rb+, Cs+, Mg2+, Ca2+, Sr2+, Ba2+, Cr3+, Fe2+, Co2+, Ni2+, Cu2+, Zn2+, Pb2+) was investigated by spectrophotometric and electrochemical methods in CH3CN. p-EAC exhibits decreased absorbance at 353nm in the presence of Cr3+, Fe2+, Pb2+, and Cu2+. The spectra of p-EAC showed bathochromic shift in absorption maximum on the addition of Cr3+, Fe2+, or Pb2+ with decreasing order of absorbance (Cr3+ >Fe2+ >Pb2+), and on the other hand, hypsochromic shift on the addition of Cu2+. This leads to the selective coloration from light green to orange and colorless for Cr3+ and Cu2+ that can be detected by the naked eye, respectively. In electrochemistry experiments, p-EAC also showed two different types of voltammetric changes toward Cr3+, Fe2+, or Pb2+, and toward Cu2+, whereas no significant changes occurred in the presence of the other metal ions. Nonlinear fitting curve procedure was used to determine a logarithmic value of 5.20, 4.92, 3.54 and 4.80 for the stability constants of the complex of p-EAC with Cr3+, Fe2+, Pb2+, and Cu2+, respectively.
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      PubDate: 2017-02-05T09:37:21Z
      DOI: 10.1016/j.saa.2017.01.055
      Issue No: Vol. 178 (2017)
       
  • New design of experiment combined with UV–Vis spectroscopy for
           extraction and estimation of polyphenols from Basil seeds, Red seeds,
           Sesame seeds and Ajwan seeds
    • Authors: Fazal Mabood; Syed Abdullah Gilani; Javid Hussain; Sulaiman Alshidani; Said Alghawi; Mohammed Albroumi; Saif Alameri; Farah Jabeen; Zahid Hussain; Ahmed Al-Harrasi; Zahra K.M. Al Abri; Saima Farooq; Zakira Naureen; Ahmad Hamaed; M. Rasul Jan; Jasmin Shah
      Pages: 14 - 18
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Fazal Mabood, Syed Abdullah Gilani, Javid Hussain, Sulaiman Alshidani, Said Alghawi, Mohammed Albroumi, Saif Alameri, Farah Jabeen, Zahid Hussain, Ahmed Al-Harrasi, Zahra K.M. Al Abri, Saima Farooq, Zakira Naureen, Ahmad Hamaed, M. Rasul Jan, Jasmin Shah
      New experimental designs for the extraction of polyphenols from different seeds including Basil seed, Red seed, Sesame seeds and Ajwan seeds were investigated. Four variables the concentration and volume of methanol and NaOH solutions as well as the temperature and time of extraction were varied to see their effect on total phenol extraction. The temperature was varied in the range from 25°C to 200°C while the time in the range from 30 to 200minutes. Response surface methodology was used to optimize the extraction parameters. The estimation of polyphenols was measured through phenols reduction UV–Vis spectroscopic method of phosphotungstic-phosphomolybdic acids (Folin-Ciocalteu's reagent). Calibration curve was made by using tannic acid as a polyphenols standard in the concentration range from 0.1 to 10ppm. The regression line obtained shows the value of correlation coefficient i.e. R =0.930 and Root mean square error of cross validation (RMSEC) value of 0.0654. The Basil seeds were found containing the highest amount of total phenols i.e. 785.76mg/100g. While the Sesame seeds having the least amount i.e. 33.08mg/100g. The Ajwan seeds and the Red seeds are containing the medium amounts i.e. 379mg/100g and 220.54mg/100g respectively.
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      PubDate: 2017-02-05T09:37:21Z
      DOI: 10.1016/j.saa.2017.01.051
      Issue No: Vol. 178 (2017)
       
  • Terahertz spectra of l-phenylalanine and its monohydrate
    • Authors: Tingting Pan; Shaoping Li; Tao Zou; Zheng Yu; Bo Zhang; Chenyang Wang; Jianbing Zhang; Mingxia He; Hongwei Zhao
      Pages: 19 - 23
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Tingting Pan, Shaoping Li, Tao Zou, Zheng Yu, Bo Zhang, Chenyang Wang, Jianbing Zhang, Mingxia He, Hongwei Zhao
      The low-frequency vibrational property of l-phenylalanine (l-Phe) and l-phenylalanine monohydrate (l-Phe·H2O) has been investigated by terahertz time-domain spectroscopy (THz-TDS) at room and low temperature ranging from 0.5 to 4.5THz. Distinctive THz absorption spectra of the two compounds were observed. Density functional theory (DFT) calculations based on the crystal structures have been performed to simulate the vibrational modes of l-Phe and l-Phe·H2O and the results agree well with the experimental observations. The study indicates that the characterized features of l-Phe mainly originate from the collective vibration of molecules. And the characterized features of l-Phe·H2O mainly come from hydrogen bond interactions between l-Phe and water molecules. l-Phe and l-Phe·H2O were also verified by differential scanning calorimetry and thermogravimetry (DSC-TG) and powder X-ray diffraction (PXRD) examinations.
      Graphical abstract image

      PubDate: 2017-02-05T09:37:21Z
      DOI: 10.1016/j.saa.2017.01.050
      Issue No: Vol. 178 (2017)
       
  • A selective chemosensor for fluoride ion and its interaction with Calf
           Thymus DNA
    • Authors: Soumen Ghosh; Abdulla Al Masum; Aniruddha Ganguly; Md. Maidul Islam; Md. Akhtarul Alam; Nikhil Guchhait
      Pages: 24 - 31
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Soumen Ghosh, Abdulla Al Masum, Aniruddha Ganguly, Md. Maidul Islam, Md. Akhtarul Alam, Nikhil Guchhait
      The amido-Schiff base 1 (N1, N3-bis (2-nitrobenzylidene)benzene-1,3-dicabohydrazide) containing a CONH group and CHN linkage has been synthesized by the condensation between isophthalic acid dihydrazide and o-nitrobenzaldehyde. This molecule can act as a fluoride ion sensor with high selectivity and sensitivity. Presence of nitro group in the phenyl ring may be responsible for the detection of fluoride ion visually with a dramatic color change from colorless to deep red in aqueous dimethyl sulphoxide solution. This Schiff base can be used as test kit for sensing of fluoride ion in the solid state. Compound 1 can detect fluoride also in commercially available toothpaste. As the compound has adequate solubility in DMSO–water mixture (7:93, v/v) and having some hydrogen bond donor and acceptor centers, we have investigated its nature of binding with Calf Thymus-DNA (CT-DNA) using theoretical molecular modelling and other experimental methods like UV–vis spectroscopy, circular dichroic and thermal melting studies. Thermodynamic parameters have been obtained using the well known Van't Hoff's equation. From both theoretical and experimental findings it has been observed that it can interact effectively with CT-DNA with binding energy −7.55kcal/mol to −7.50kcal/mol.
      Graphical abstract image

      PubDate: 2017-02-05T09:37:21Z
      DOI: 10.1016/j.saa.2017.01.044
      Issue No: Vol. 178 (2017)
       
  • Fourier-transform infrared spectroscopy (FTIR) analysis of triclinic and
           hexagonal birnessites
    • Authors: Florence T. Ling; Jeffrey E. Post; Peter J. Heaney; James D. Kubicki; Cara M. Santelli
      Pages: 32 - 46
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Florence T. Ling, Jeffrey E. Post, Peter J. Heaney, James D. Kubicki, Cara M. Santelli
      The characterization of birnessite structures is particularly challenging for poorly crystalline materials of biogenic origin, and a determination of the relative concentrations of triclinic and hexagonal birnessite in a mixed assemblage has typically required synchrotron-based spectroscopy and diffraction approaches. In this study, Fourier-transform infrared spectroscopy (FTIR) is demonstrated to be capable of differentiating synthetic triclinic Na-birnessite and synthetic hexagonal H-birnessite. Furthermore, IR spectral deconvolution of peaks resulting from MnO lattice vibrations between 400 and 750cm−1 yield results comparable to those obtained by linear combination fitting of synchrotron X-ray absorption fine structure (EXAFS) data when applied to known mixtures of triclinic and hexagonal birnessites. Density functional theory (DFT) calculations suggest that an infrared absorbance peak at ~1628cm−1 may be related to OH vibrations near vacancy sites. The integrated intensity of this peak may show sensitivity to vacancy concentrations in the Mn octahedral sheet for different birnessites.

      PubDate: 2017-02-05T09:37:21Z
      DOI: 10.1016/j.saa.2017.01.032
      Issue No: Vol. 178 (2017)
       
  • Analysis of the binding interaction in uric acid - Human hemoglobin system
           by spectroscopic techniques
    • Authors: Magdalena Makarska-Bialokoz
      Pages: 47 - 54
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Magdalena Makarska-Bialokoz
      The binding interaction between human hemoglobin and uric acid has been studied for the first time, by UV–vis absorption and steady-state, synchronous and three-dimensional fluorescence techniques. Characteristic effects observed for human hemoglobin intrinsic fluorescence during interaction with uric acid at neutral pH point at the formation of stacking non-covalent and non-fluorescent complexes. All the calculated parameters, the binding, fluorescence quenching and bimolecular quenching rate constants, as well as Förster resonance energy transfer parameters confirm the existence of static quenching. The results of synchronous fluorescence measurements indicate that the fluorescence quenching of human hemoglobin originates both from Trp and Tyr residues and that the addition of uric acid could significantly hinder the physiological functions of human hemoglobin.
      Graphical abstract image

      PubDate: 2017-02-05T09:37:21Z
      DOI: 10.1016/j.saa.2017.01.063
      Issue No: Vol. 178 (2017)
       
  • Highly selective fluorescent and colorimetric chemosensor for detection of
           Hg2+ ion in aqueous media
    • Authors: Mohammad Zareh Jonaghani; Hassan Zali-Boeini
      Pages: 66 - 70
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Mohammad Zareh Jonaghani, Hassan Zali-Boeini
      A highly efficient and selective fluorescent and colorimetric chemosensor based on naphthothiazole skeleton was synthesized and its colorimetric and fluorescent properties were investigated. The sensor displays a rapid and highly selective colorimetric and fluorescence response toward Hg2+ without interference with other metal ions in CH3CN/H2O mixture (50/50, v/v). The detection limit for the fluorescent chemosensor S1 toward Hg2+ was 3.42×10−8 M.
      Graphical abstract image

      PubDate: 2017-02-05T09:37:21Z
      DOI: 10.1016/j.saa.2017.01.065
      Issue No: Vol. 178 (2017)
       
  • Synthesis, characterization and xanthine oxidase inhibition of
           Cu(II)–chrysin complex
    • Authors: Suyun Lin; Li Zeng; Guowen Zhang; Yijing Liao; Deming Gong
      Pages: 71 - 78
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Suyun Lin, Li Zeng, Guowen Zhang, Yijing Liao, Deming Gong
      Xanthine oxidase (XO) is a key enzyme catalyzing hypoxanthine to xanthine and then uric acid causing hyperuricemia. A Cu(II) complex of chrysin was synthesized and characterized by UV–vis absorption, Fourier transform infrared, nuclear magnetic resonance (1H NMR) and mass spectroscopy studies. The interaction of Cu(II)-complex with XO was investigated by spectroscopic methods and molecular simulation. The Cu(II)-chrysin complex exhibited a better inhibitory ability (IC50 =0.82±0.034μM) against XO than its corresponding ligands chrysin and Cu2+ in a mix-competitive manner. The binding affinity of Cu(II)-chrysin complex with XO was much higher than that of chrysin. The hydrogen bonds and van der Waals forces played main roles in the binding. Analysis of circular dichroism spectra indicated that the complex induced the conformational change of XO. The molecular simulation found that the Cu(II)-chrysin complex inserted into the active cavity of XO with Cu acting as a bridge, occupying the catalytic center of the enzyme to avoid entry of the substrate xanthine, leading to the inhibition of XO. This study may provide new insights into the inhibition mechanism of the Cu(II)-chrysin complex as a promising XO inhibitor and its potential application for the treatment of hyperuricemia.
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      PubDate: 2017-02-05T09:37:21Z
      DOI: 10.1016/j.saa.2017.01.056
      Issue No: Vol. 178 (2017)
       
  • The effects of second electron acceptor group on the performance of
           tetrazole-based nanocrystalline TiO2 sensitizers in DSSCs
    • Authors: Zahra Jafari Chermahini; Alireza Najafi Chermahini; Hossein A. Dabbagh; Behzad Rezaei; Neda Irannejad
      Pages: 79 - 85
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Zahra Jafari Chermahini, Alireza Najafi Chermahini, Hossein A. Dabbagh, Behzad Rezaei, Neda Irannejad
      Three new organic sensitizers with two electron acceptor groups were synthesized and applied to nanocrystalline TiO2 solar cells. The ethyl 2-(1H-tetrazol-5-yl) acetate, (2H-tetrazol-5-yl) acrylonitrile and 1H-tetrazole-5-acetic acid moieties were introduced to the triphenylamine as electron acceptor groups. The photophysical, electrochemical and photovoltaic properties of the solar cells based on the synthesized sensitizers were studied and compared with their counterparts of single electron acceptor type. Quantum chemical calculations were also carried out to consideration of the electronic and optical properties of these dyes. The dye with the (2H-tetrazol-5-yl) acrylonitrile electron acceptors showed the absorption maxima in the longer wavelength, compared to the dyes with ethyl 2-(1H-tetrazol-5-yl) acetate and 1H-tetrazole-5-acetic acid. The solar cell based on the dye with 1H-tetrazole-5-acetic acid showed the highest conversion efficiency of 3.53% (open circuit voltage=569mV, short circuit photocurrent density=11.50mAcm−2, and fill factor of 54% under AM 1.5G conditions). The results also showed that the dyes with two electron acceptor groups gave the higher performance than the dyes with single electron acceptor.
      Graphical abstract image

      PubDate: 2017-02-05T09:37:21Z
      DOI: 10.1016/j.saa.2017.01.061
      Issue No: Vol. 178 (2017)
       
  • Unravel the interaction of protoporphyrin IX with reduced graphene oxide
           by vital spectroscopic techniques
    • Authors: Mariadoss Asha Jhonsi; Chandrasekaran Nithya; Arunkumar Kathiravan
      Pages: 86 - 93
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Mariadoss Asha Jhonsi, Chandrasekaran Nithya, Arunkumar Kathiravan
      Probing interaction between dyes and reduced graphene oxide (rGO) is of contemporary research interest. Since, rGO is widely used as electron acceptor in photovoltaic and optoelectronic devices. Hence, we have investigated the interaction between protoporphyrin IX (PPIX) and rGO by vital spectroscopic techniques. The adsorption of PPIX on rGO is studied by Attenuated total reflection-Fourier transform infrared (ATR-FTIR) and X-ray photoelectron spectroscopic (XPS) measurements. The fluorescence quenching measurements are also performed and the fluorescence intensity of PPIX is quenched by rGO. The quenching of PPIX with rGO is evaluated by the Stern–Volmer equation and time-resolved fluorescence lifetime studies. The results revealed that the fluorescence quenching of PPIX with rGO is due to the static quenching mechanism. The dominant process for this quenching has been attributed to the process of electron transfer from excited state PPIX to rGO. Fluorescence lifetime measurements were used to calculate the rate of electron transfer process between excited state of PPIX and rGO. Transient absorption studies demonstrated the formation of PPIX cation radical for the evidence of electron transfer between PPIX and rGO.
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      PubDate: 2017-02-05T09:37:21Z
      DOI: 10.1016/j.saa.2017.01.059
      Issue No: Vol. 178 (2017)
       
  • FTIR spectroscopic study of the complex formation between H+ and DMSO in
           Nafion
    • Authors: A.I. Karelin; R.R. Kayumov; E.A. Sanginov; Yu.A. Dobrovolsky
      Pages: 94 - 104
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): A.I. Karelin, R.R. Kayumov, E.A. Sanginov, Yu.A. Dobrovolsky
      Nafion membranes plasticized with dimethyl sulfoxide (DMSO) have been examined at room temperature using the vacuum ATR - FTIR spectroscopic technique in the range 50–4000cm−1. The amount of the plasticizer corresponds to the molecular ratio n =DMSO/H+ =1.2, 2.3, 4.8, 7.0, 9.7 and 13.3. The medium intensity band with two maxima at 780 and 853cm−1 have been assigned to the ν(SO) stretching vibrations of the H+(DMSO)2 complex. The possible reason of ν(SO) splitting is symmetry decrease of hydrogen bond under the influence of the anion group SO3 − electric field. Whereas the mutual association of free DMSO molecules in Nafion leads to appearance of weak band at 86cm−1 assigned to the dipole-dipole interactions.
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      PubDate: 2017-02-05T09:37:21Z
      DOI: 10.1016/j.saa.2017.01.062
      Issue No: Vol. 178 (2017)
       
  • Corrigendum to “High selectivity of colorimetric detection of
           p-nitrophenol based on Ag nanoclusters” [Spectrochim. Acta A Mol.
           Biomol. Spectrosc. 171 (2017) 449–453]
    • Authors: Fei Qu; Ping Chen; Shuyun Zhu; Jinmao You
      First page: 105
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Fei Qu, Ping Chen, Shuyun Zhu, Jinmao You


      PubDate: 2017-02-05T09:37:21Z
      DOI: 10.1016/j.saa.2017.01.060
      Issue No: Vol. 178 (2017)
       
  • New dyes for DSSC containing triphenylamine based extended donor:
           Synthesis, photophysical properties and device performance
    • Authors: Palas Baran Pati; Wenxing Yang; Sanjio S. Zade
      Pages: 106 - 113
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Palas Baran Pati, Wenxing Yang, Sanjio S. Zade
      Three new triphenylamine based dyes with Donor-Donor-Spacer-Acceptor (D-D-π-A) arrangement were designed and synthesized by convenient synthetic pathway. Unsymmetrical extended donor part may help to reduce the aggregation of dyes on the semiconductor surface. Wide range of absorption in the visible spectrum, electrochemical studies and theoretical optimization suggest that these dyes can be good members for DSSC. Further to check the performance of these dyes in device the solar cells were developed using iodine free Co-based electrolyte. Electronic characterisation concludes that devices based on D6 have the highest power conversion efficiency (4.7%) mostly due to an improved electron lifetime, which therefore improves both the V OC and J SC of the devices.
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      PubDate: 2017-02-05T09:37:21Z
      DOI: 10.1016/j.saa.2017.01.048
      Issue No: Vol. 178 (2017)
       
  • Thiocyanate mediated structural diversity in phenol based “end-off”
           compartmental ligand complexes of group 12 metal ions: Studies on their
           photophysical properties and phosphatase like activity
    • Authors: Jaydeep Adhikary; Prateeti Chakraborty; Sugata Samanta; Ennio Zangrando; Sanjib Ghosh; Debasis Das
      Pages: 114 - 124
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Jaydeep Adhikary, Prateeti Chakraborty, Sugata Samanta, Ennio Zangrando, Sanjib Ghosh, Debasis Das
      The reaction of a pentadentate compartmental ligand LH, namely 4-tert-Butyl-2,6-bis-[(2-pyridin-2-yl-ethylimino)-methyl]-phenol, with group 12 metal ions (ZnII, CdII, HgII) followed by addition of NaSCN afforded one discrete dinuclear complex [Zn2(L)(SCN)3](1), and two polymeric 1D species [Cd2.5(L)(SCN)3(AcO)]n (2) and [Hg2(L)(SCN)3]n (3). All the complexes have been structurally characterized by single crystal X-ray diffraction. The crystal structure of the complexes reveals different coordination modes of thiocyanate anion that affect the different topology detected in the compounds: the anions are μ1-NCS and μ1,1-NCS connected in complex 1, while μ1,3-NCS bridging mode is observed in 2, and μ1-SCN and μ1,3-NCS in 3. The polymeric Hg complex of the bicompartmental ligand system here reported is unprecedented. Detail study of their photophysical properties including the phosphorescence spectra at 77K has been done. Phosphatase like activity of all the three complexes has been performed in DMSO-H2O medium and their activity follows the order of 1 > 2 >> 3.
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      PubDate: 2017-02-05T09:37:21Z
      DOI: 10.1016/j.saa.2017.01.041
      Issue No: Vol. 178 (2017)
       
  • Investigation of the complex structure, comparative DNA-binding and DNA
           cleavage of two water-soluble mono-nuclear lanthanum(III) complexes and
           cytotoxic activity of chitosan-coated magnetic nanoparticles as drug
           delivery for the complexes
    • Authors: Zahra Asadi; Neda Nasrollahi; Hamidreza Karbalaei-Heidari; Vaclav Eigner; Michal Dusek; Nabiallah Mobaraki; Roya Pournejati
      Pages: 125 - 135
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Zahra Asadi, Neda Nasrollahi, Hamidreza Karbalaei-Heidari, Vaclav Eigner, Michal Dusek, Nabiallah Mobaraki, Roya Pournejati
      Two water-soluble mono-nuclear macrocyclic lanthanum(III) complexes of 2,6-diformyl-4-methylphenol with 1,3-diamino-2-propanol (C 1 ) or 1,3-propylenediamine (C 2 ) were synthesized and characterized by UV–Vis, FT-IR, 13C and 1H NMR spectroscopy and elemental analysis. C 1 complex was structurally characterized by single-crystal X-ray diffraction, which revealed that the complex was mononuclear and ten-coordinated. The coordination sites around lanthanum(III) were occupied with a five-dentate ligand, two bidentate nitrates, and one water molecule. The interaction of complexes with DNA was studied in buffered aqueous solution at pH7.4. UV–Vis absorption spectroscopy, emission spectroscopy, circular dichroism (CD) and viscometric measurements provided clear evidence of the intercalation mechanism of binding. The obtained intrinsic binding constants (K b ) 9.3×103 and 1.2×103 M−1 for C 1 and C 2 , respectively confirmed that C 1 is better intercalator than C 2 . The DNA docking studies suggested that the complexes bind with DNA in a groove binding mode with the binding affinity of C 1 > C 2 . Moreover, agarose gel electrophoresis study of the DNA-complex for both compounds revealed that the C 1 intercalation cause ethidium bromide replacement in a competitive manner which confirms the suggested mechanism of binding. Finally, the anticancer experiments for the treated cancerous cell lines with both synthesized compounds show that these hydrophilic molecules need a suitable carrier to pass through the hydrophobic nature of cell membrane efficiently.
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      PubDate: 2017-02-11T10:50:02Z
      DOI: 10.1016/j.saa.2017.01.037
      Issue No: Vol. 178 (2017)
       
  • Aziridinyl-substituted benzo-1,4-quinones: A preliminary investigation on
           the theoretical and experimental studies of their structure and
           spectroscopic properties
    • Authors: Jonas Šarlauskas; Jelena Tamulienė; Narimantas Čėnas
      Pages: 136 - 141
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Jonas Šarlauskas, Jelena Tamulienė, Narimantas Čėnas
      The detailed structure, chemical and spectroscopic properties of the derivatives of the selected 2,5-bis(1-aziridinyl)-benzo-1,4-quinone conformers were studied by applying quantum chemical and experimental methods. The relationship between the structure and chemical activity of the selected 3 bifunctional bioreductive quinonic anticancer agents - aziridinyl benzoquinones (AzBQ compounds) was obtained. The results obtained showed that the position of aziridine rings influenced by the chemical activity of the investigated compound were more significant than the substitutions of the benzene ring of the AzBQ compounds. The solvents influencing this activity were obtained, too.
      Graphical abstract image

      PubDate: 2017-02-11T10:50:02Z
      DOI: 10.1016/j.saa.2017.01.058
      Issue No: Vol. 178 (2017)
       
  • Study of Cr→SmA phase transition and hydrogen bonding in four-ring
           bent-core liquid crystal
    • Authors: Swapnil Singh; Harshita Singh; Poonam Tandon; Nirmalangshu Chakraborty; N.V.S. Rao; A.P. Ayala
      Pages: 142 - 150
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Swapnil Singh, Harshita Singh, Poonam Tandon, Nirmalangshu Chakraborty, N.V.S. Rao, A.P. Ayala
      A newly designed asymmetrical four-ring bent-core compound (4′-n-decyloxyphenylazo)-phenyl-4-yl-3-[N-(4′-n-octadecyloxy-2-hydroxybenzylidene) amino]-2-methyl benzoate exhibiting liquid crystalline behavior was synthesized and characterized. The thermal and textural morphology were studied using differential scanning calorimetry and polarizing optical microscopy, respectively. The study of hydrogen bonding and dynamics of the phase transition has been performed at the molecular level using temperature dependent Fourier transform infrared (FTIR) spectroscopy. The spectral analysis of OH, CH2/CH3, CO, and CN stretching vibrational bands revealed clear signatures of Cr→SmA phase transition at 125°C. Density functional theory has been adopted for the geometry optimization and conformational study of the monomer using the B3LYP/6-31G(d) method. The conformational analysis has been performed to predict the most stable conformer along with the possible conformers using one-dimensional potential energy scan employing the same level of theory. The combination of experimental findings and theoretical analysis helped to understand the mechanism of phase transitions at the molecular level.
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      PubDate: 2017-02-11T10:50:02Z
      DOI: 10.1016/j.saa.2017.01.067
      Issue No: Vol. 178 (2017)
       
  • A new fluorogenic sensing platform for salicylic acid derivatives based on
           π-π and NH-π interactions between electron-deficient and electron-rich
           aromatics
    • Authors: Anup Pandith; Giridhari Hazra; Hong-Seok Kim
      Pages: 151 - 159
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Anup Pandith, Giridhari Hazra, Hong-Seok Kim
      A novel simple fluorescent probe was designed for the recognition of electron-rich salicylic acid derivatives (SAs). The imidazole-appended aminomethyl perylene probe 1 selectively differentiated between electron-rich amino-SAs and electron-deficient nitro-SAs in EtOH, exhibiting the highest selectivity and sensitivity toward 5-aminosalicylic acid (5-ASA) and showing strong 1:1 binding (K a =1.37×107 M−1). This high selectivity and sensitivity resulted from the synergistic multiple hydrogen bonding interactions of secondary amine and imidazole units and π-π interactions between electron-rich and electron-deficient rings, along with the unusual NH-π interactions between 5-ASA and the perylene moiety of 1. The limit of detection (LOD) for 5-ASA in EtOH was 0.012ppb.
      Graphical abstract image

      PubDate: 2017-02-11T10:50:02Z
      DOI: 10.1016/j.saa.2017.01.053
      Issue No: Vol. 178 (2017)
       
  • Selective recognition of Cu (II) and Fe (III) using a pyrene based
           chemosensor
    • Authors: Daulat Phapale; Akshay Gaikwad; Dipanwita Das
      Pages: 160 - 165
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Daulat Phapale, Akshay Gaikwad, Dipanwita Das
      A pyrene-based colorimetric chemosensor 1-(pyren-1-yl)-N,N-bis-(pyridine-2-ylmethyl)methanamine (1) was synthesised for selective detection of Cu (II) and Fe (III) over the other metal cations Ni2+, Mg2+, Cd2+, Hg2+, Na+, K+, Ca2+, Co2+, Cr3+, Pb2+ and Zn2+. The significant changes in UV–vis absorption band of receptor 1 and the emergence of 660nm band in presence of Cu2+ ion indicates the selective binding of Cu2+ ion as compared to other metal cations which could easily be identified from the naked eye strong colour change. Job plots suggest a 1:1 and 2:1 stoichiometric binding of Cu2+ and Fe3+, respectively, which was evidenced by ESI-MS analysis. Chemosensor 1 explores a cost-effective and selective colorimetric sensor for naked eye detection of trace amount of Cu2+ and Fe3+ ions in presence of other metal cations.
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      PubDate: 2017-02-11T10:50:02Z
      DOI: 10.1016/j.saa.2017.01.064
      Issue No: Vol. 178 (2017)
       
  • Qualitative observation of reversible phase change in astrochemical
           ethanethiol ices using infrared spectroscopy
    • Authors: S Pavithraa; R R J Methikkalam; P Gorai; J -I Lo; A Das; B N Raja Sekhar; T Pradeep; B -M Cheng; N J Mason; B Sivaraman
      Pages: 166 - 170
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): S Pavithraa, R R J Methikkalam, P Gorai, J -I Lo, A Das, B N Raja Sekhar, T Pradeep, B -M Cheng, N J Mason, B Sivaraman
      Here we report the first evidence for a reversible phase change in an ethanethiol ice prepared under astrochemical conditions. InfraRed (IR) spectroscopy was used to monitor the morphology of the ice using the SH stretching vibration, a characteristic vibration of thiol molecules. The deposited sample was able to switch between amorphous and crystalline phases repeatedly under temperature cycles between 10K and 130K with subsequent loss of molecules in every phase change. Such an effect is dependent upon the original thickness of the ice. Further work on quantitative analysis is to be carried out in due course whereas here we are reporting the first results obtained.
      Graphical abstract image

      PubDate: 2017-02-11T10:50:02Z
      DOI: 10.1016/j.saa.2017.01.023
      Issue No: Vol. 178 (2017)
       
  • Reaction of tetracycline with biologically relevant chloramines
    • Authors: J. Benavides; P. Barrias; N. Piro; A. Arenas; A. Orrego; E. Pino; L. Villegas; E. Dorta; A. Aspée; C. López-Alarcón
      Pages: 171 - 180
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): J. Benavides, P. Barrias, N. Piro, A. Arenas, A. Orrego, E. Pino, L. Villegas, E. Dorta, A. Aspée, C. López-Alarcón
      Helicobacter pylori (H. pylori) infection triggers inflammatory processes with the consequent production of hypochlorous acid (HOCl), monochloramine (NH2Cl), and protein-derived chloramines. As the therapy for eradicating H. pylori is partially based on the use of tetracycline, we studied the kinetic of its consumption elicited by HOCl, NH2Cl, N-chloro-n-butylamine (NHCl-But, used as a lysine-derived chloramine model), and lysozyme-derived chloramines. In the micromolar concentration range, tetracycline reacted rapidly with HOCl, generating in the first few seconds intermediates of short half-life. In contrast, a slow tetracycline consumption was observed in the presence of high NH2Cl and NHCl-But concentrations (millimolar range). Similar chlorinated products of tetracycline were identified by mass spectrometry, in the presence of HOCl and NH2Cl. These results evidenced that tautomers of tetracycline are pivotal intermediates in all reactions. In spite of the low reactivity of chloramines towards tetracycline, it is evident that, in the concentration range where they are produced in a H. pylori infection (millimolar range), the reactions lead to oxidation and/or chlorination of tetracycline. This kind of reactions, which were also observed triggered by lysozyme-derived chloramines, could limit the efficiency of the tetracycline-based therapy.
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      PubDate: 2017-02-11T10:50:02Z
      DOI: 10.1016/j.saa.2017.02.001
      Issue No: Vol. 178 (2017)
       
  • Time-resolved spectral analysis of Radachlorin luminescence in water
    • Authors: V.P. Belik; I.M. Gadzhiev; I.V. Semenova; O.S. Vasyutinskii
      Pages: 181 - 184
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): V.P. Belik, I.M. Gadzhiev, I.V. Semenova, O.S. Vasyutinskii
      We report results of spectral- and time-resolved study of Radachlorin photosensitizer luminescence in water in the spectral range of 950–1350nm and for determination of the photosensitizer triplet state and the singlet oxygen lifetimes responsible for singlet oxygen generation and degradation. At any wavelength within the explored spectral range the luminescence decay contained two major contributions: a fast decay at the ns time scale and a slow evolution at the μs time scale. The fast decay was attributed to electric dipole fluorescence transitions in photosensitizer molecules and the slow evolution to intercombination phosphorescence transitions in singlet oxygen and photosensitizer molecules. Relatively high-amplitude ns peak observed at all wavelengths suggests that singlet oxygen monitoring with spectral isolation methods alone, without additional temporal resolution can be controversial. In the applied experimental conditions the total phosphorescence signal at any wavelength contained a contribution from the photosensitizer triplet state decay, while at 1274nm the singlet oxygen phosphorescence dominated. The results obtained can be used for optimization of the methods of singlet oxygen monitoring and imaging.
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      PubDate: 2017-02-11T10:50:02Z
      DOI: 10.1016/j.saa.2017.01.066
      Issue No: Vol. 178 (2017)
       
  • Dual time-resolved temperature-jump fluorescence and infrared spectroscopy
           for the study of fast protein dynamics
    • Authors: Caitlin M. Davis; Michael J. Reddish; R. Brian Dyer
      Pages: 185 - 191
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Caitlin M. Davis, Michael J. Reddish, R. Brian Dyer
      Time-resolved temperature-jump (T-jump) coupled with fluorescence and infrared (IR) spectroscopy is a powerful technique for monitoring protein dynamics. Although IR spectroscopy of the polypeptide amide I mode is more technically challenging, it offers complementary information because it directly probes changes in the protein backbone, whereas, fluorescence spectroscopy is sensitive to the environment of specific side chains. With the advent of widely tunable quantum cascade lasers (QCL) it is possible to efficiently probe multiple IR frequencies with high sensitivity and reproducibility. Here we describe a dual time-resolved T-jump fluorescence and IR spectrometer and its application to study protein folding dynamics. A Q-switched Ho:YAG laser provides the T-jump source for both time-resolved IR and fluorescence spectroscopy, which are probed by a QCL and Ti:Sapphire laser, respectively. The Ho:YAG laser simultaneously pumps the time-resolved IR and fluorescence spectrometers. The instrument has high sensitivity, with an IR absorbance detection limit of <0.2mOD and a fluorescence sensitivity of 2% of the overall fluorescence intensity. Using a computer controlled QCL to rapidly tune the IR frequency it is possible to create a T-jump induced difference spectrum from 50ns to 0.5ms. This study demonstrates the power of the dual time-resolved T-jump fluorescence and IR spectroscopy to resolve complex folding mechanisms by complementary IR absorbance and fluorescence measurements of protein dynamics.
      Graphical abstract image

      PubDate: 2017-02-11T10:50:02Z
      DOI: 10.1016/j.saa.2017.01.069
      Issue No: Vol. 178 (2017)
       
  • Reagent-free simultaneous determination of glucose and cholesterol in
           whole blood by FTIR-ATR
    • Authors: Zhigang Li; Hong Lv; Tianhe Li; Guangyuan Si; Qiaoyun Wang; Jiangtao Lv; Xiaofei Hu
      Pages: 192 - 197
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Zhigang Li, Hong Lv, Tianhe Li, Guangyuan Si, Qiaoyun Wang, Jiangtao Lv, Xiaofei Hu
      Reagent-free determination of multiple analytes is an active and promising field of research in clinical analysis. In this work, the determination of glucose and cholesterol in whole blood using Fourier transform infrared (FTIR) spectroscopy equipped with an attenuated total reflectance (ATR) accessory was performed. A comprehensive sample selection rule in multi space based on SPXY was proposed, termed C-SPXY. The core idea is to make full use of different derivative spectra space to construct the calibration set which preserves the more effective information. On this basis, a partial least squares (PLS) regression fusion modeling method was also presented aiming at improving prediction accuracy of glucose and cholesterol concentration in whole blood samples. Compared with other methods based on single spectra space, the proposed fusion model based on multi spectra space C-SPXY method provides smaller RMSEP values. Experimental results demonstrate that the proposed method and model provides superior predictive power and holds a good application prospect in the field of clinical analysis.
      Graphical abstract image

      PubDate: 2017-02-11T10:50:02Z
      DOI: 10.1016/j.saa.2017.02.002
      Issue No: Vol. 178 (2017)
       
  • A new isoindoline–based highly selective “turn-on” fluorescent
           chemodosimeter for detection of mercury ion
    • Authors: Hassan Zali-Boeini; Mohammad Zareh Jonaghani; Negar Fadaei; Hadi Amiri Rudbari
      Pages: 198 - 202
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Hassan Zali-Boeini, Mohammad Zareh Jonaghani, Negar Fadaei, Hadi Amiri Rudbari
      A new isoindoline–based highly efficient turn-on fluorescent chemodosimeter S with a thioamide functionality as a binding site for selective detection of Hg2+ ion has been developed. The chemodosimeter S showed an extreme selectivity for detection of Hg2+ ion among various two and three-valent metal ions in acetonitrile/water (70/30, v/v). It was found that, in the presence of Hg2+ ion the non-fluorescent chemodosimeter S was efficiently and rapidly desulfurized to the corresponding highly fluorescent amide 1. A good linear relationship was shown between the fluorescence intensity and the concentration of Hg2+ within the range of 0–1μM, with a detection limit of 2.03×10−8 M.
      Graphical abstract image

      PubDate: 2017-02-11T10:50:02Z
      DOI: 10.1016/j.saa.2017.02.003
      Issue No: Vol. 178 (2017)
       
  • A zinc fluorescent sensor used to detect mercury (II) and hydrosulfide
    • Authors: Jae Min Jung; Jae Jun Lee; Eunju Nam; Mi Hee Lim; Cheal Kim; Roger G. Harrison
      Pages: 203 - 211
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Jae Min Jung, Jae Jun Lee, Eunju Nam, Mi Hee Lim, Cheal Kim, Roger G. Harrison
      A zinc sensor based on quinoline and morpholine has been synthesized. The sensor selectively fluoresces in the presence of Zn2+, while not for other metal ions. Absorbance changes in the 350nm region are observed when Zn2+ binds, which binds in a 1:1 ratio. The sensor fluoresces due to Zn2+ above pH values of 6.0 and in the biological important region. The Zn2+-sensor complex has the unique ability to detect both Hg2+ and HS−. The fluorescence of the Zn2+-sensor complex is quenched when it is exposed to aqueous solutions of Hg2+ with sub-micromolar detection levels for Hg2+. The fluorescence of the Zn2+-sensor complex is also quenched by aqueous solutions of hydrosulfide. The sensor was used to detect Zn2+ and Hg2+ in living cells.
      Graphical abstract image

      PubDate: 2017-02-11T10:50:02Z
      DOI: 10.1016/j.saa.2017.02.006
      Issue No: Vol. 178 (2017)
       
  • Spectroscopic study of honey from Apis mellifera from different regions in
           Mexico
    • Authors: C Frausto-Reyes; R Casillas-Peñuelas; JL Quintanar-Stephano; E Macías-López; JM Bujdud-Pérez; I Medina-Ramírez
      Pages: 212 - 217
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): C Frausto-Reyes, R Casillas-Peñuelas, JL Quintanar-Stephano, E Macías-López, JM Bujdud-Pérez, I Medina-Ramírez
      The objective of this study was to analyze by Raman and UV–Vis-NIR Spectroscopic techniques, Mexican honey from Apis Mellífera, using representative samples with different botanic origins (unifloral and multifloral) and diverse climates. Using Raman spectroscopy together with principal components analysis, the results obtained represent the possibility to use them for determination of floral origin of honey, independently of the region of sampling. For this, the effect of heat up the honey was analyzed in relation that it was possible to greatly reduce the fluorescence background in Raman spectra, which allowed the visualization of fructose and glucose peaks. Using UV–Vis-NIR, spectroscopy, a characteristic spectrum profile of transmittance was obtained for each honey type. In addition, to have an objective characterization of color, a CIE Yxy and CIE L*a*b* colorimetric register was realized for each honey type. Applying the principal component analysis and their correlation with chromaticity coordinates allowed classifying the honey samples in one plot as: cutoff wavelength, maximum transmittance, tones and lightness. The results show that it is possible to obtain a spectroscopic record of honeys with specific characteristics by reducing the effects of fluorescence.
      Graphical abstract image

      PubDate: 2017-02-11T10:50:02Z
      DOI: 10.1016/j.saa.2017.02.009
      Issue No: Vol. 178 (2017)
       
  • Benzimidazole acrylonitriles as multifunctional push-pull chromophores:
           Spectral characterisation, protonation equilibria and nanoaggregation in
           aqueous solutions
    • Authors: Ema Horak; Robert Vianello; Marijana Hranjec; Svjetlana Krištafor; Grace Karminski Zamola; Ivana Murković Steinberg
      Pages: 225 - 233
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Ema Horak, Robert Vianello, Marijana Hranjec, Svjetlana Krištafor, Grace Karminski Zamola, Ivana Murković Steinberg
      Heterocyclic donor-π-acceptor molecular systems based on an N,N-dimethylamino phenylacrylonitrile benzimidazole skeleton have been characterised and are proposed for potential use in sensing applications. The benzimidazole moiety introduces a broad spectrum of useful multifunctional properties to the system including electron accepting ability, pH sensitivity and compatibility with biomolecules. The photophysical characterisation of the prototropic forms of these chromophores has been carried out in both solution and on immobilisation in polymer films. The experimental results are further supported by computational determination of pK a values. It is noticed that compound 3 forms nanoaggregates in aqueous solutions with aggregation-induced emission (AIE) at 600nm. All the systems demonstrate spectral pH sensitivity in acidic media which shifts towards near-neutral values upon immobilisation in polymer films or upon aggregation in an aqueous environment (compound 3). The structure-property relationships of these functional chromophores, involving their spectral characteristics, acid-base equilibria, pK a values and aggregation effects have been determined. Potential applications of the molecules as pH and biomolecular sensors are proposed based on their pH sensitivity and AIE properties.
      Graphical abstract image

      PubDate: 2017-02-18T11:59:56Z
      DOI: 10.1016/j.saa.2017.02.011
      Issue No: Vol. 178 (2017)
       
  • Spectrophotometric determination of meclizine hydrochloride and pyridoxine
           hydrochloride in laboratory prepared mixtures and in their pharmaceutical
           preparation
    • Authors: Maha M. Ibrahim; Eman S. Elzanfaly; Mohamed B. El-Zeiny; Nesreen K. Ramadan; Khadiga M. Kelani
      Pages: 234 - 238
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Maha M. Ibrahim, Eman S. Elzanfaly, Mohamed B. El-Zeiny, Nesreen K. Ramadan, Khadiga M. Kelani
      In this paper, three rapid, simple, accurate and precise spectrophotometric methods were developed for the determination of meclizine hydrochloride in the presence of pyridoxine hydrochloride without previous separation. The methods under study are dual wavelength (DWL), ratio difference (RD) and continuous wavelet transform (CWT). On the other hand, pyridoxine hydrochloride (PYH) was determined directly at 291nm. The methods obey Beer's law in the range of (5–50μg/mL) for both compounds. All the methods were validated according to the ICH guidelines where the accuracy was found to be 98.29, 99.59, 100.42 and 100.62% for DWL, RD, CWT and PYH; respectively. Moreover the precision of the methods were calculated in terms of %RSD and it was found to be 0.545, 0.372, 1.287 and 0.759 for DWL, RD,CWT and PYH; respectively. The selectivity of the proposed methods was tested using laboratory prepared mixtures and assessed by applying the standard addition technique. So, they can be used for the routine analysis of pyridoxine hydrochloride and meclizine hydrochloride in quality-control laboratories.
      Graphical abstract image

      PubDate: 2017-02-18T11:59:56Z
      DOI: 10.1016/j.saa.2017.02.013
      Issue No: Vol. 178 (2017)
       
  • Structural investigation of the cocrystal formed between 5-fluorocytosine
           and fumaric acid based on vibrational spectroscopic technique
    • Authors: Yong Du; Qiang Cai; Jiadan Xue; Qi Zhang; Dan Qin
      Pages: 251 - 257
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Yong Du, Qiang Cai, Jiadan Xue, Qi Zhang, Dan Qin
      The vibrational spectra of 5-fluorocytosine, fumaric acid and their cocrystal were measured using terahertz time-domain spectroscopy (THz-TDS) and Raman spectroscopy at room temperature. Experimental THz results show that the cocrystal has distinct fingerprint spectra in terahertz region. The absorption peaks observed in the terahertz spectra of the cocrystal were at 0.61 and 0.91THz. These are quite different from corresponding raw starting materials. Raman spectra also show similar results about differences between the cocrystal and corresponding raw starting materials. Density functional theory (DFT) was used to simulate the structure of the possible salt form and the cocrystal form between 5-fluorocytosine and fumaric acid. The theoretical terahertz result shows that the cocrystal form has absorption at 0.62 and 0.87THz, which is in agreement with the experimental result. The theoretical Raman result also indicates that the cocrystal form has more possibilities than the salt form. So, it is more reasonable that the structure between 5-fluorocytosine and fumaric acid could be the corresponding cocrystal form. The characteristic bands of the cocrystal between 5-fluorocytosine and fumaric acid are also assigned based on the simulation results from the DFT calculation.
      Graphical abstract image

      PubDate: 2017-02-18T11:59:56Z
      DOI: 10.1016/j.saa.2017.02.004
      Issue No: Vol. 178 (2017)
       
  • Altering intra- to inter-molecular hydrogen bonding by dimethylsulfoxide:
           A TDDFT study of charge transfer for coumarin 343
    • Authors: Xiaochun Liu; Hang Yin; Hui Li; Ying Shi
      Pages: 1 - 5
      Abstract: Publication date: 15 April 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 177
      Author(s): Xiaochun Liu, Hang Yin, Hui Li, Ying Shi
      DFT and TDDFT methods were carried out to investigate the influences of intramolecular and intermolecular hydrogen bonding on excited state charge transfer for coumarin 343 (C343). Intramolecular hydrogen bonding is formed between carboxylic acid group and carbonyl group in C343 monomer. However, in dimethylsulfoxide (DMSO) solution, DMSO ‘opens up’ the intramolecular hydrogen bonding and forms solute-solvent intermolecular hydrogen bonded C343-DMSO complex. Analysis of frontier molecular orbitals reveals that intramolecular charge transfer (ICT) occurs in the first excited state both for C343 monomer and complex. The results of optimized geometric structures indicate that the intramolecular hydrogen bonding interaction is strengthened while the intermolecular hydrogen bonding is weakened in excited state, which is confirmed again by monitoring the shifts of characteristic peaks of infrared spectra. We demonstrated that DMSO solvent can not only break the intramolecular hydrogen bonding to form intermolecular hydrogen bonding with C343 but also alter the mechanism of excited state hydrogen bonding strengthening.
      Graphical abstract image

      PubDate: 2017-01-22T16:24:35Z
      DOI: 10.1016/j.saa.2017.01.022
      Issue No: Vol. 177 (2017)
       
  • A novel acidic pH fluorescent probe based on a benzothiazole derivative
    • Authors: Qiujuan Ma; Xian Li; Suxiang Feng; Beibei Liang; Tiqiang Zhou; Min Xu; Zhuoyi Ma
      Pages: 6 - 13
      Abstract: Publication date: 15 April 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 177
      Author(s): Qiujuan Ma, Xian Li, Suxiang Feng, Beibei Liang, Tiqiang Zhou, Min Xu, Zhuoyi Ma
      A novel acidic pH fluorescent probe 1 based on a benzothiazole derivative has been designed, synthesized and developed. The linear response range covers the acidic pH range from 3.44 to 6.46, which is valuable for pH researches in acidic environment. The evaluated pKa value of the probe 1 is 4.23. The fluorescence enhancement of the studied probe 1 with an increase in hydrogen ions concentration is based on the hindering of enhanced photo-induced electron transfer (PET) process. Moreover, the pH sensor possesses a highly selective response to H+ in the presence of metal ions, anions and other bioactive small molecules which would be interfere with its fluorescent pH response. Furthermore, the probe 1 responds to acidic pH with short response time that was less than 1min. The probe 1 has been successfully applied to confocal fluorescence imaging in live HeLa cells and can selectively stain lysosomes. All of such good properties prove it can be used to monitoring pH fluctuations in acidic environment with high sensitivity, pH dependence and short response time.
      Graphical abstract image

      PubDate: 2017-01-22T16:24:35Z
      DOI: 10.1016/j.saa.2017.01.024
      Issue No: Vol. 177 (2017)
       
  • Erratum to “A novel strategy for spectrophotometric simultaneous
           determination of amitriptyline and nortriptyline based on derivation with
           a quinonoid compound in serum samples” [Spectrochim. Acta A Mol. Biomol.
           Spectrosc. 168, 2016, 235–243]
    • Authors: Amir Farnoudiyan-Habibi; Bakhshali Massoumi; Mehdi Jaymand
      First page: 14
      Abstract: Publication date: 15 April 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 177
      Author(s): Amir Farnoudiyan-Habibi, Bakhshali Massoumi, Mehdi Jaymand


      PubDate: 2017-01-22T16:24:35Z
      DOI: 10.1016/j.saa.2017.01.025
      Issue No: Vol. 177 (2017)
       
  • Raman spectrum reveals Mesenchymal stem cells inhibiting HL60 cells growth
    • Authors: Xin Su; Shaoyin Fang; Daosen Zhang; Qinnan Zhang; Xiaoxu Lu; Jindong Tian; Jinping Fan; LiyunZhong
      Pages: 15 - 19
      Abstract: Publication date: 15 April 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 177
      Author(s): Xin Su, Shaoyin Fang, Daosen Zhang, Qinnan Zhang, Xiaoxu Lu, Jindong Tian, Jinping Fan, LiyunZhong
      Though some research results reveals that Mesenchymal stem cells (MSCs) have the ability of inhibiting tumor cells proliferation, it remains controversial about the precise interaction mechanism during MSCs and tumor cells co-culture. In this study, combing Raman spectroscopic data and principle component analysis (PCA), the biochemical changes of MSCs or Human promyelocytic leukemia (HL60) cells during their co-culture were presented. The obtained results showed that some main Raman peaks of HL60 assigned to nucleic acids or proteins were greatly higher in intensity in the late stage of co-culture than those in the early stage of co-culture while they were still lower relative to the control group, implicating that the effect of MSCs inhibiting HL60 proliferation appeared in the early stage but gradually lost the inhibiting ability in the late stage of co-culture. Moreover, some other peaks of HL60 assigned to proteins were decreased in intensity in the early stage of co-culture relative to the control group but rebounded to the level similar to the control group in the late stage, showing that the content and structure changes of these proteins might be generated in the early stage but returned to the original state in the late stage of co-culture. As a result, in the early stage of MSCs-HL60 co-culture, along with the level of Akt phosphorylation of HL60 was lowered relative to its control group, the proliferation rate of HL60 cells was decreased. And in the late stage of co-culture, along with the level of Akt phosphorylation was rebounded, the reverse transfer of Raman peaks within 875–880cm−1 appeared, thus MSCs lost the ability to inhibit HL60 growth and HL60 proliferation was increased. In addition, it was observed that the peak at 811cm−1, which is a marker of RNA, was higher in intensity in the late stage than that in the control group, indicating that MSCs might be differentiated into myofibroblast-like MSCs. In addition, PCA results also exhibited that the physiological state of MSCs can be separated by the first two main components of PC1 or PC2 easily, and the effect of MSCs inhibiting HL60 growth was greatly associated with the time of co-culture.
      Graphical abstract image

      PubDate: 2017-01-22T16:24:35Z
      DOI: 10.1016/j.saa.2017.01.021
      Issue No: Vol. 177 (2017)
       
  • Characterization, catalyzed water oxidation and anticancer activities of a
           NIR BODIPY-Mn polymer
    • Authors: Ya-Quan Lan; Ke-Jing Xiao; Yun-Jie Wu; Qiu-Yun Chen
      Pages: 28 - 32
      Abstract: Publication date: 15 April 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 177
      Author(s): Ya-Quan Lan, Ke-Jing Xiao, Yun-Jie Wu, Qiu-Yun Chen
      To obtain near-IR absorbing biomaterials as fluorescence cellular imaging and anticancer agents for hypoxic cancer cell, a nano NIR fluorescence Mn(III/IV) polymer (PMnD) was spectroscopically characterized. The PMnD shows strong emission at 661nm when excited with 643nm. Furthermore, PMnD can catalyze water oxidation to generate dioxygen when irradiated by red LED light (10W). In particular, the PMnD can enter into HepG-2 cells and mitochondria. Both anticancer activity and the inhibition of the expression of HIF-1α for PMnD were concentration dependent. Our results demonstrate that PMnD can be developed as mitochondria targeted imaging agents and new inhibitors for HIF-1 in hypoxic cancer cells.
      Graphical abstract image

      PubDate: 2017-01-22T16:24:35Z
      DOI: 10.1016/j.saa.2017.01.030
      Issue No: Vol. 177 (2017)
       
  • Tunable luminescence and enhanced photocatalytic activity for Eu(III)
           doped Bi2WO6 nanoparticles
    • Authors: Haidong Gu; Lei Yu; Juan Wang; Min Ni; Tingting Liu; Feng Chen
      Pages: 58 - 62
      Abstract: Publication date: 15 April 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 177
      Author(s): Haidong Gu, Lei Yu, Juan Wang, Min Ni, Tingting Liu, Feng Chen
      A series of Eu(III) doped Bi2WO6 nanoparticles were synthesized by a hydrothermal process. The obtained Bi2WO6:Eu(III) nanoparticles were characterized by XRD, SEM, luminescence spectrophotometer and DRS. The XRD and TEM results indicate that the Eu(III) doping concentration has no influence on the phase and morphology. However, the Eu(III) doping can tune the luminescence and enhance the photocatalytic activity of Bi2WO6. With the increases of Eu3+ doping concentrations, the emission intensity of WO6 6− group decreases nut the photocatalytic activity increases. The tunable luminescence of Bi2WO6:Eu(III) nanoparticles results from the energy transfer from WO6 6− group to Eu(III) ion. The enhanced performance can be ascribed to efficient separation of electron and hole pairs after doping Eu(III) into the Bi2WO6 lattice.
      Graphical abstract image

      PubDate: 2017-01-22T16:24:35Z
      DOI: 10.1016/j.saa.2017.01.034
      Issue No: Vol. 177 (2017)
       
  • The ability of the Coincidence Doppler Broadening Spectroscopy to
           characterize polymers containing different chemical elements
    • Authors: J. Yang; T. Zhang; L.A. Han; X.Z. Cao; R.S. Yu; B.Y. Wang
      Pages: 97 - 103
      Abstract: Publication date: 15 April 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 177
      Author(s): J. Yang, T. Zhang, L.A. Han, X.Z. Cao, R.S. Yu, B.Y. Wang
      Hydrocarbon polymers, O-containing, F-containing and Cl-containing polymers are comprehensively studied by Coincidence Doppler Broadening Spectroscopy (CDBS). It is shown that for polymers with different chemical structure, CDBS results can effectively distinguish polar groups C O, CCl, and CF. For polymers with similar chemical structure, the intensity of the element-specific peak in the CDBS ratio curve is dependent not only on the fraction of free positrons, but also on the content of characteristic atom in polymer repeated unit, and the polarity of the polymer molecule. For polymers containing several different polar groups, such as PCTFE (CF & CCl) and PFA (CF & C O), whether the element-specific peak appears or not depends on the amount of the polar groups and its positron capture ability. This work may provide insights into potential applications of CDBS for studying complex polymer systems.
      Graphical abstract image

      PubDate: 2017-01-28T08:30:02Z
      DOI: 10.1016/j.saa.2017.01.028
      Issue No: Vol. 177 (2017)
       
  • Accurate spectroscopic calculations of the 22 Λ-S states and 60Ω
           states of the PS+ cation
    • Authors: Hui Liu; Deheng Shi Jinfeng Sun Zunlue Zhu
      Abstract: Publication date: 5 May 2017
      Source:Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, Volume 178
      Author(s): Hui Liu, Deheng Shi, Jinfeng Sun, Zunlue Zhu
      This work studied the potential energy curves of 22 Λ-S states, which were yielded from the first two dissociation limits, P(4Su)+S+(4Su) and P+(3Pg)+S(3Pg), of the PS+ cation. The potential energy curves were calculated employing the CASSCF method, which was followed by the internally contracted MRCI approach with Davidson correction. Core- valence correlation and scalar relativistic corrections as well as basis set extrapolation were included. Of these 22 Λ-S states, only the 35Σ+ state was repluse without the spin-orbit coupling effect, whereas the 35Σ+, 15Δ, 25Σ+, and 15Σ− states were repulse with the spin-orbit coupling effect accounted for. The 21Π and 23Π states had double wells, but the first well of the 23Π state had no vibrational levels and the first well of 21Π state had only one vibrational state. The avoided crossings were found between the 11Π and 21Π states and between the d3Π and 23Π states. The 25Σ+, 15Π, 15Δ, b3Δ, and c3Σ− states were inverted with the spin-orbit coupling effect taken into account. The 15Δ, 25Σ+, 15Σ−, and 21Π states were weakly bound. The spectroscopic properties were evaluated and compared with the experimental and other theoretical results. The Franck-Condon factors of some electronic transitions between different Λ-S states were determined. The vibrational levels of several states were predicted. The spin-orbit coupling effect on the spectroscopic parameters was discussed. Analyses show that the spectroscopic results obtained here can be expected to be reliably predicted ones.
      Graphical abstract image

      PubDate: 2017-02-05T09:37:21Z
       
 
 
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