Rapid Point-of-Care Assay by SERS Detection of SARS-CoV-2 Virus and Its Variants

Abstract

Addressing the spread of coronavirus disease 2019 (COVID-19) has highlighted the need for rapid, accurate, and low-cost diagnostic methods that detect specific antigens for SARS-CoV-2 infection. Tests for COVID-19 are based on reverse transcription PCR (RT-PCR), which requires laboratory services and is time-consuming. Here, by targeting the SARS-CoV-2 spike protein, we present a point-of-care SERS detection platform that specifically detects SARS-CoV-2 antigen in one step by captureing substrates and detection probes based on aptamer-specific recognition. Using the pseudovirus, without any pretreatment, the SARS-CoV-2 virus and its variants were detected by a handheld Raman spectrometer within 5 min. The limit of detection (LoD) for the pseudovirus was 124 TU μL –1 (18 fM spike protein), with a linear range of 250–10,000 TU μL –1 . Moreover, this assay can specifically recognize the SARS-CoV-2 antigen without cross reacting with specific antigens of other coronaviruses or influenza A. Therefore, the platform has great potential for application in rapid point-of-care diagnostic assays for SARS-CoV-2.

Bovine Serum Albumin-Protected Gold Nanoclusters for Sensing of SARS-CoV-2 Antibodies and Virus

“…These results indicate that we can quantitate SARS-CoV-2 in a variety of media at levels similar to or better than most lateral flow or ELISA tests. − In addition, a comparison of different biosensors recently published to detect the SARS-CoV-2 virus is listed in Table S2. Our method also has a comparable or better detection limit than some of the listed methods. − …”

“Dramatic Growth” of Microbial Aerosols for Visualization and Accurate Counting of Bioaerosols

“…Hence, to obtain accurate statistical results, we used a subtraction method to subtract the number of background impurities by designing control groups (Figure S11). For the coronavirus, we set a gradient from 10 3 to 10 5 TU/mL, meeting most respiratory virus detection requirements, to prove the feasibility of growth at different pseudovirus-SARS-CoV-2 concentrations. , Figure d,e shows the particle size analysis and linear fitting curves of the virus microspheres. The virus microspheres were around 1.5 μm in size, and the total particle number was consistent with the preset concentration.…”

Surface-enhanced Raman spectroscopy as a powerful method for the analysis of Chinese herbal medicines

“…In order to improve specificity in SERS detection, functionalized probes are usually developed and used to modify the substrate. [61][62][63] Although the affinity screening method based on immobilized proteins has demonstrated dramatic advances in screening bioactive compounds from natural products, [64][65][66] it is still challenged by long screening time, binder loss and low contents in samples. To address the urgent needs, Zhao et al have employed a dual-functional SERS probe to screen and detect bioactive ingredients binding to the target protein from Gardenia jasminoides extract.…”