Authors:
Yu Ji;Jintang Shang;Guoliang Li;Jin Zhang;Jianfeng Zhang;
Pages: 1 - 4 Abstract: In this letter, we present a novel microfabricated shaped rubidium vapor cell with 3 cm optical path length for miniaturized atomic magnetometers. The novel shaped rubidium vapor cells are manufactured by a wafer-level fabrication process, and the process consists of the following three steps sequentially: first, wet etching to form oblong shallow cavity arrays; second, anodic bonding, glass reflowing, and wet etching to obtain a glass wafer with shaped structures; third, anodic bonding and chemical reaction to obtain the wafer-level shaped rubidium vapor cells. A miniaturized atomic magnetometer using the novel shaped rubidium vapor cell is characterized in the geomagnetic environment. The performance of the novel shaped rubidium vapor cell is compared with the traditional microfabricated rubidium vapor cell of a “glass–silicon–glass” sandwich structure. Results show that the measured geomagnetic field is 47.85 μT. It is demonstrated that the dispersive signal's slope of the novel shaped rubidium vapor cell is 15 times larger than that of the traditional one. Results also indicate that the miniaturized atomic magnetometer working in the geomagnetic environment has a magnetic noise spectral density of 3.5 pT/Hz1/2 from 1 to 2 Hz. PubDate:
Feb. 2020
Issue No:Vol. 4, No. 2 (2020)
Authors:
Seyed Reza Mahmoodi;Pengfei Xie;Mark Allen;Mehdi Javanmard;
Pages: 1 - 4 Abstract: We present a novel method for label-free detection of tumor necrosis factor alpha (TNF-α) in serum after immobilization by electric field. Detection of proteins in blood using label-free impedance-based techniques is difficult due to high salt concentration of the matrix, which results in charge screening. The nanowell array sensor provides enhanced electrochemical sensitivity by electric field focusing in the nanoscale volume wells. Here, an on-chip multiwell plate sensing platform was fabricated and tested. The sensor performance through testing in mouse serum at protein concentrations between 10 and 500 ng/l has been demonstrated. This detection modality is advantageous to many label-free electronic sensors in that signal power scales will increase in salt concentration, thus improving the sensitivity of the platform. PubDate:
Feb. 2020
Issue No:Vol. 4, No. 2 (2020)
Authors:
Muneer M. Al-Zu'bi;Ananda Sanagavarapu Mohan;
Pages: 1 - 4 Abstract: Drug-eluting stents have been considered to be an effective technique to reduce the severity of atherosclerotic stenosis. Recent technological advances have opened the door for developing new and innovative smart cardiovascular stents by integrating various electronic components and sensors to improve health monitoring and diagnosis. Rupture of atherosclerotic plaque represents the major cause of cardiovascular disease, such as heart attacks, due to blockages of the arterial lumen. Pentraxin-3 (PTX3) is a novel localized inflammatory biomarker associated with the development of atherosclerosis and plaque vulnerability. In this letter, we propose a biosensor interface platform for monitoring the plaque vulnerability via detection and prediction of the inflammatory biomarker (PTX3). We propose mathematical and stochastic models using a molecular communication paradigm for detection of PTX3 molecules in the atherosclerotic arterial wall using a biosensor attached to a vascular stent inside the artery. The proposed platform and models can help in the localized sensing of the atherosclerotic biomarkers for monitoring of the plaque progression and for early warning of certain disorders, such as heart attack. PubDate:
Feb. 2020
Issue No:Vol. 4, No. 2 (2020)
Hybrid journal (It can contain Open Access articles)
