Designing and fabrication of electrochemical nano-biosensor for the fast detection of SARS-CoV-2-RNA

SARS-CoV-2 caused a global panic among populations. Rapid diagnostic procedures for the virus are crucial for disease control. Thus, the designed signature probe from a highly conserved region of the virus was chemically immobilized onto the nanostructured-AuNPs/WO3-screen printed electrodes. Different concentrations of the matched oligonucleotides were spiked to test the specificity of the hybridization affinity whereas the electrochemical impedance spectroscopy was used for tracking the electrochemical performance. After a full assay optimization, limits of detection and quantification were calculated based on linear regression and were valued at 298 and 994 fM, respectively. Further, the high performance of the fabricated RNA-sensor chips was confirmed after testing the interference status in the presence of the mismatched oligos in one nucleotide and completely one. Worthy to mention that the single-stranded matched oligos can be hybridized to the immobilized probe in 5 min at room temperature. The designed disposable sensor chips are capable of detecting the virus genome directly. Therefore, the chips are a rapid tool for SARS-CoV-2 detection.

Automated summary

A designed signature probe based on nanostructured-AuNPs/WO3 screen printed electrodes was immobilized for rapid diagnostic of SARS-CoV-2. The detection limits and quantification limits were optimized to 298 and 994 fM respectively. The study also confirmed the hybridization of the probe with the virus genome in 5 minutes at room temperature, making it a rapid tool for SARS-CoV-2 detection.