DNA/RNA Electrochemical Biosensing Devices a Future Replacement of PCR Methods for a Fast Epidemic Containment

Abstract

Pandemics require a fast and immediate response to contain potential infectious carriers. In the recent 2020 Covid-19 worldwide pandemic, authorities all around the world have failed to identify potential carriers and contain it on time. Hence, a rapid and very sensitive testing method is required. Current diagnostic tools, reverse transcription PCR (RT-PCR) and real-time PCR (qPCR), have its pitfalls for quick pandemic containment such as the requirement for specialized professionals and instrumentation. Versatile electrochemical DNA/RNA sensors are a promising technological alternative for PCR based diagnosis. In an electrochemical DNA sensor, a nucleic acid hybridization event is converted into a quantifiable electrochemical signal. A critical challenge of electrochemical DNA sensors is sensitive detection of a low copy number of DNA/RNA in samples such as is the case for early onset of a disease. Signal amplification approaches are an important tool to overcome this sensitivity issue. In this review, the authors discuss the most recent signal amplification strategies employed in the electrochemical DNA/RNA diagnosis of pathogens.

Affinity Sensors for the Diagnosis of COVID-19

“…In some electrochemical sensors, NA hybridization [ 63 ] includes an electrochemical reaction, which is further used for the quantitation of the detected NA fragment concentration and thus to the concentration of SARS-CoV-2 virus. Electrochemical NA biosensors are classified according to the types of reporter NA (label-free or labeled) and through the signal generation principle (reagent-free or reagent-dependent) [ 68 ].…”

“…The choice of the most efficient signal amplification method is the key aspect that is used to resolve this task. The molecular approaches are classified into (1) NA-based amplification methods (enzyme-mediated isothermal amplification of NA), (2) nanomaterials-based methods (large surface area for the loading of capture NA; nanomaterials as reporter probes), and (3) enzyme-mediated signal amplification (enzymes are connected with NA hybridization system) [ 68 ]. Different electrochemical methods are employed for the quantitation of amplified signals, namely, electrochemical impedance spectroscopy (EIS) [ 69 , 70 ], chronoamperometry [ 71 ], pulsed amperometric detection [ 63 , 72 ], square wave voltammetry [ 73 ], differential pulse voltammetry (DPV) [ 74 ], and cyclic voltammetry (CV) [ 75 , 76 ].…”

Point-of-Care PCR Assays for COVID-19 Detection

“…The pre-COVID era witnessed the emergence of PCR-free electrochemical assays for detecting different nucleic acid targets, including microRNA, viral RNA and DNA, and cancer-related genes [ 43 , 44 , 45 ]. Perhaps the research community has been confident that electrochemical assays can compete with the existing PCR technology in terms of sensitivity and turnaround times and eliminate the use of costly reagents and dyes [ 46 ]. There have been some studies on PCR-integrated electrochemical biosensors in the last 5 years.…”

A Review on the Development of Gold and Silver Nanoparticles-Based Biosensor as a Detection Strategy of Emerging and Pathogenic RNA Virus

“…The electrochemical biosensor allows a detectable signal from the DNA hybridization event to be amplified, thus enabling a quantitative detection of RNA/DNA. The signal amplification approaches in the electrochemical sensing devices are crucial to increase the sensitivity of nucleic acid detection [ 106 ]. For this purpose, advanced materials-based electrodes, such as carbon, mercury, gold, and graphene have been incorporated in the surface modification of the electrodes and tested for nucleic acid detection.…”