A CRISPR‐Cas12a‐derived biosensor enabling portable personal glucose meter readout for quantitative detection of SARS‐CoV‐2

Abstract

Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) has spread rapidly throughout the whole world and caused significant difficulties in the prevention and control of the epidemic. In this case, several detection methods have been established based on nucleic acid diagnostic techniques and immunoassays to achieve sensitive and specific detection of SARS‐CoV‐2. However, most methods are still largely dependent on professional instruments, highly trained operators, and centralized laboratories. These limitations gravely diminish their practicality and portability. Herein, a clustered regularly interspaced short palindromic repeats (CRISPR) Cas12a based assay was developed for portable, rapid and sensitive of SARS‐CoV‐2. In this assay, samples were quickly pretreated and amplified by reverse transcription recombinase‐aided amplification under mild conditions. Then, by combining the CRISPR Cas12a system and a glucose‐producing reaction, the signal of the virus was converted to that of glucose, which can be quantitatively read by a personal glucose meter in a few seconds. Nucleocapsid protein gene was tested as a model target, and the sensitivity for quantitative detection was as low as 10 copies/μl, which basically meet the needs of clinical diagnosis. In addition, with the advantages of lower material cost, shorter detection time, and no requirement for professional instrument in comparison with quantitative reverse transcription‐polymerase chain reaction, this assay is expected to provide a powerful technical support for the early diagnosis and intervention during epidemic prevention and control.

Science's Response to CoVID‐19

“…Similar detection stratagems using Cas12 collateral activity [173] have also been reported [174] . In one instance, called “DETECTR” amplification of cDNA (encoding viral E‐ and N‐genes) and human RNase P (included as a positive control) was performed using RT‐LAMP (which has also been used for SHERLOCK) [175] . Then a viral cDNA sequence was detected using a specific guide RNA that triggered cleavage of a self‐quenched ssDNA fluorescent probe.…”

Detection of Infectious Viruses Using CRISPR-Cas12-Based Assay

“…There are several other SARS-CoV-2 detection approaches that have been reported recently that work as a single-step reaction, integrated portable devices for the purpose of POCT, such as CRISPR optical detection of anisotropy (CODA), CRISPR-assisted detection (CASdetec), personal glucose meter–CRISPR assay (PGM-CRISPR), an integrated portable droplet magnetofluidic (DM) device, and CRISPR-fluorescence detection system (CRISPR-FDS) [ 38 , 39 , 40 , 41 , 42 , 43 , 44 ]. While these approaches are already functional POCT devices, they are capable of detecting SARS-CoV-2 only.…”

COVID-19 Diagnostic Methods and Detection Techniques

“…Therefore, researchers are studying different types of biosensors to make the detection more convenient and suitable for at-home test. These biosensors include optical, electrical, and electrochemical sensors targeting different virus gene, nucleic acid or antibody ( Kim et al, 2021 ; Huang et al, 2021 ; Ke et al, 2021 ; Liu et al, 2021b ; Eissa and Zourob, 2021 ; Zhao et al, 2021 ; Mojsoska et al, 2021 ; Alafeef et al, 2020 ; Li et al, 2020a ; Funari et al, 2020 ; Wang et al, 2020a ).…”