We use cookies to understand how you use our site and to improve your experience. This includes personalizing content and advertising. To learn more, click here. By continuing to use our site, you accept our use of cookies. Cookie Policy.

Features Partner Sites Information LinkXpress
Sign In
Advertise with Us

Download Mobile App





Researchers Develop Accurate, High-Speed, Portable Bi-Functional Electrical Detector for COVID-19

By HospiMedica International staff writers
Posted on 28 Jan 2021
Print article
Image: Extraction of viral RNA (Photo courtesy of Science China Press)
Image: Extraction of viral RNA (Photo courtesy of Science China Press)
Researchers have developed an unprecedented accurate, rapid, and portable electrical detector based on the use of graphene field-effect transistors (G-FETs) for the detection of RNA from COVID-19 patients.

The detection system developed by scientists at the Peking University (Beijing, China) mainly consists of two parts: a plug-and-play packaged biosensor chip and a home-developed electrical measurement machine. The unique feature of this method is that the extent of hybridization between the ss-DNA probe and viral RNA can be directly converted to the current change of graphene channels without repetition of the PCR process, thus affording an ultra-low limit of detection (LOD) of 0.1 fg/mL for the detection of the RNA-dependent RNA polymerase (RdRp) gene target of SARS-CoV-2.

Furthermore, this method was validated using clinical samples collected from many patients with COVID-19 infection and healthy individuals as well, and the testing results were in full agreement with those of PCR-based optical methods. The entire process, precluding the extraction of detection targets from oropharyngeal swabs, requires approximately 10 min. Because it does not involve time-consuming PCR step nor expensive instruments, this detection system enables massive point-of-care testing of COVID-19, outside of specialized diagnostic laboratories, with the advantage of high accuracy, sensitivity and low cost.

Notably, false negative results are inevitable in the course of nucleic acid testing; thus, the use of immunodetection as an auxiliary technique is important in the diagnosis of COVID-19 patients, especially those with suspected diseases. By replacing the ss-DNA probe with a SARS-CoV-2 antigen protein, this detection system can also detect SARS-CoV-2 IgM and IgG antibodies with an ultra-low LOD of 1 fg/mL. Immunoassays of serum specimens of COVID-19 patients and healthy subjects matched excellently with those of PCR-based optical methods.

This detecting system exhibits obvious advantages of high sensitivity, rapid speed (10 min for RNA analysis and 5 min for immunoassay), and bifunction (both RNA analysis and immunoassay). These advantages enable high-throughput point-of-care testing, which may facilitate management of the current severe public health crisis. Furthermore, this detection system offers a universal methodology that is ready for immediate application in rapid detection of novel viruses in future.

Related Links:
Peking University


Print article

Channels

Business

view channel
Illustration

Machine Learning Algorithm Identifies Deteriorating Patients in Hospital Who Need Intensive Care

Researchers have developed a machine learning algorithm that could significantly improve clinicians’ ability to identify hospitalized patients whose condition is deteriorating to the extent that they need... Read more
Copyright © 2000-2021 Globetech Media. All rights reserved.