Electrochemical Detection of Viral Nucleic Acids by DNA Nanolock-Based Porous Electrode Device

Abstract

Developing rapid, sensitive, and facile nucleic acid detection technologies is of paramount importance for preventing and controlling infectious diseases. Benefiting from the advantages such as rapid response, low cost, and simple operation, electrochemical impedance spectroscopy holds great promise for point-of-care nucleic acid detection. However, the sensitivity of electrochemical impedance spectroscopy for low molecular weight nucleic acids testing is still limited. This work presents a DNA nanolock-based porous electrode to improve the sensitivity of electrochemical impedance spectroscopy. Once the target nucleic acids are recognized by the DNA probes, the pore-attached DNA nanolock caused remarkable impedance amplification by blocking the nanopores. Taking SARS-CoV-2 nucleic acid as a model analyte, the detection limit of the porous electrode was as low as 0.03 fM for both SARS-CoV-2 RNA and DNA. The integration of a porous electrode with a wireless communicating unit generates a portable detection device that could be applied to direct SARS-CoV-2 nucleic acid testing in saliva samples. The portable device could effectively distinguish the COVID-19 positive and negative samples, showing a sensitivity of 100% and a specificity of 93%. Owing to its rapid, ultrasensitive, specific, and portable features, the as-designed DNA nanolock and porous electrode-based portable device holds great promise as a point-of-care platform for real-time screening of COVID-19 and other epidemics.

Peptide-Based Flavivirus Biosensors: From Cell Structure to Virological and Serological Detection Methods

“…Numerous benefits are provided by electrochemical techniques for the development of biosensors. This method offers relatively low cost, simple fabrication, fast response, high sensitivity, possible miniaturization, and different reporting signals (e.g., voltage, current, overall power output, or electrochemical impedance) . Electrochemical biosensors often rely on variations in the electrode surface current or impedance as a result of surface or redox reactions.…”

DNA-modified Prussian blue nanozymes for enhanced electrochemical biosensing

“…46–50 With the advancement of the systematic evolution of ligands by exponential enrichment (SELEX), 51,52 an increasing number of nucleic acid aptamers are available to replace protein antibodies for analyte identification. They can identify a wide range of small-molecule compounds, 24,53,54 proteins, 55–57 viruses, 58,59 bacteria, 60,61 and cells. 62,63 In addition, DNAzymes (catalytic nucleic acids) are single-stranded DNA sequences that, in the presence of cofactors such as copper ions, 64,65 lead ions, 66,67 and histidine, 68 are capable of catalyzing the cleavage or ligation of nucleic acid substrates similar to ribozymes.…”

In2O3/NC/Au NPs Nanocomposites for the Electrochemical Detection of Skeletonema costatum

“…An electrochemical DNA biosensor is widely regarded as a precise, quick, inexpensive, and miniaturized technology, making it more suitable for on-site detection. − Such systems incorporate DNA probes as biorecognition elements for specific detection and quantification of targets designed by the Watson–Crick pairing principle. − Nanomaterials are often used as electrode materials to increase probe loading, accelerate the rate of electron transfer at the electrode surface, and thereby improve the sensitivity of electrochemical DNA biosensors. In 2 O 3 is a new semiconductor nanomaterial that has attracted attention for its low resistivity, high mobility, and good chemical stability. − N-doped carbon (NC) can effectively enhance the electron transfer efficiency of metal oxides .…”