An electrochemical biosensor for sensitive analysis of the SARS-CoV-2 RNA

Abstract

The pandemic of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) is continuously worsening globally, herein we have proposed an electrochemical biosensor for the sensitive monitoring of SARS-CoV-2 RNA. The presence of target RNA firstly triggers the catalytic hairpin assembly circuit and then initiates terminal deoxynucleotidyl transferase-mediated DNA polymerization. Consequently, a large number of long single-stranded DNA products can be produced, and these negatively charged DNA products will bind a massive of positively charged electroactive molecular of Ru(NH 3 ) 6 3+ due to the electrostatic adsorption. Therefore, significantly amplified electrochemical signals can be generated for sensitive analysis of SARS-CoV-2 RNA in the range of 0.1–1000 pM with the detection limit as low as 26 fM. Besides the excellent distinguishing ability for SARS-CoV-2 RNA against single-base mismatched RNA, the proposed biosensor can also be successfully applied to complex matrices, as well as clinical patient samples with high stability, which shows great prospects of clinical application.

Peptide-based simple detection of SARS-CoV-2 with electrochemical readout

“…In such biosensors, bioreceptors are anchored on the working electrode surface to directly bind to target molecules specifically, generating changes in the interfacial properties in a concentration-dependent manner [ [18] , [19] , [20] ]. The SARS-CoV-2 has also been detected electrochemically by immunosensors [ 14 , [21] , [22] , [23] , [24] , [25] , [26] , [27] , [28] , [29] , [30] , [31] , [32] ] and genosensors [ [33] , [34] , [35] , [36] ]. Furthermore, outstanding features of biosensors have been exploited in the detection of other viruses [ 37 , 38 ], pathogens [ 39 ], other infections [ 18 ], cancer biomarkers [ [40] , [41] , [42] ] and other diseases-related biomarkers [ 43 ] demonstrating to be promising analytical tools that can help to solve current diagnosis limitations [ 44 ].…”

Recent advances in the biosensors application for the detection of bacteria and viruses in wastewater

“…Furthermore, Peng et al have proposed a SARS-CoV-2 detection method that uses a catalytic assembly circuit and DNA polymerization in the presence of targeted RNA [82] . The biorecognition elements used were hairpin structures and were immobilized on the surface for specificity.…”

“…The biorecognition elements used were hairpin structures and were immobilized on the surface for specificity. The sensor has shown its capability in SARS-CoV-2 RNA detection at concentrations as low as 2.6 × 10 −6 nM, along with linear responses in concentration ranges between 10 −5 and 1 nM [82] . In a similar study targeting SARS-CoV-2 RNA, Zhao et al reported the development of a biosensor that does not require any pretreatment steps, such as nucleic acid amplification and reverse transcription, which conventional methods often require [76] .…”

Loop-mediated isothermal amplification-based electrochemical sensor for detecting SARS-CoV-2 in wastewater samples

“…Among the wide variety of transduction mechanisms for detecting nucleic acid amplification, one can find electrochemical-based sensors [27] , [28] , optical devices [29] , colorimetric assays [30] , luminescence-based sensors [31] , and surface plasmon resonance apparatus [32] , to mention only a few. Particularly, electrochemical transduction has demonstrated its ability to provide a cost-effective alternative to circumvent manufacturing and integration processes to robust devices.…”