Toward a Home Test for COVID-19 Diagnosis: DNA Machine for Amplification-Free SARS-CoV-2 Detection in Clinical Samples

Recent Advances in DNA Nanotechnology-Based Sensing Platforms for Rapid Virus Detection

Several major viral pandemics in history have significantly impacted the public health of human beings. The COVID-19 pandemic has further underscored the critical need for early detection and screening of infected individuals. However, current detection techniques are confronted with deficiencies in sensitivity and accuracy, restricting the capability of detecting trace amounts of viruses in human bodies and in the environments. The advent of DNA nanotechnology has opened up a feasible solution for rapid and sensitive virus determination. By harnessing the designability and addressability of DNA nanostructures, a range of rapid virus sensing platforms have been proposed. This review overviewed the recent progress, application, and prospect of DNA nanotechnology-based rapid virus detection platforms. Furthermore, the challenges and developmental prospects in this field were discussed.

Multicomponent DNAzyme Nanomachines: Structure, Applications, and Prospects

Nucleic acids (NAs) are important components of living organisms responsible for the storage and transmission of hereditary information. They form complex structures that can self-assemble and bind to various biological molecules. DNAzymes are NAs capable of performing simple chemical reactions, which makes them potentially useful elements for creating DNA nanomachines with required functions. This review focuses on multicomponent DNA-based nanomachines, in particular on DNAzymes as their main functional elements, as well as on the structure of DNAzyme nanomachines and their application in the diagnostics and treatment of diseases. The article also discusses the advantages and disadvantages of DNAzyme-based nanomachines and prospects for their future applications. The review provides information about new technologies and the possibilities of using NAs in medicine.

DNAzyme Nanomachine with Fluorogenic Substrate Delivery Function: Advancing Sensitivity in Nucleic Acid Detection

We have developed a hook-equipped DNA nanomachine (HDNM) for the rapid detection of specific nucleic acid sequences without a preamplification step. HDNM efficiently unwinds RNA structures and improves the detection sensitivity. Compared to the hookless system, HDNM offers an 80-fold and 13-fold enhancement in DNA and RNA detection, respectively, reducing incubation time from 3 to 1 h.

A Novel DNAzyme-Based Fluorescent Biosensor for Detection of RNA-Containing Nipah Henipavirus

Nipah virus (NiV) is a zoonotic RNA virus which infects humans and animals in Asian countries. Infection in humans occurs in different forms, from asymptomatic infection to fatal encephalitis, and death occurred in 40-70% of those infected in outbreaks that occurred between 1998 and 2018. Modern diagnostics is carried out by real-time PCR to identify pathogens or by ELISA to detect antibodies. Both technologies are labor-intensive and require the use of expensive stationary equipment. Thus, there is a need to develop alternative simple, fast and accurate test systems for virus detection. The aim of this study was to develop a highly specific and easily standardized system for the detection of Nipah virus RNA. In our work, we have developed a design for a Dz_NiV biosensor based on a split catalytic core of deoxyribozyme 10-23. It was shown that the assembly of active 10-23 DNAzymes occurred only in the presence of synthetic target Nipah virus RNA and that this was accompanied by stable fluorescence signals from the cleaved fluorescent substrates. This process was realized at 37 °C, pH 7.5, and in the presence of magnesium ions, with a 10 nM limit of detection achieved for the synthetic target RNA. Constructed via a simple and easily modifiable process, our biosensor may be used for the detection of other RNA viruses.