DNA Multiway Junction Based Lateral Flow Assay for Visualized Detection of Different Types of Targets

Abstract

Lateral flow assay owns advantages of easy operation, visual detection, and portable use. However, since the strip fabrication requires specific nanomaterial modification, zones pretreating/spraying, and particular capture unit immobilization, the as-prepared strip usually can detect just one type of target. To detect a new target, nanomaterial remodification and strip refabrication are needed, which is laborious, costly, and limited by access to the strip device. Here, we propose a DNA multiway junction based lateral flow assay facing different types of targets. Two assistant strands, named α and β, and a molecular beacon (MB) are designed, so as to form a DNA four-way junction with DNA/RNA nucleic acids or to a form DNA three-way junction with small molecules, proteins, and enzymes. The DNA multiway junction acts as a bridging complex to link DNA-modified gold nanoparticles on the test zone for coloration. We demonstrate the as-prepared lateral flow strip for detection of HBV viral DNA fragment, microRNA, ATP, thrombin, and terminal deoxynucleotidyl transferase (TdT). The DNA multiway junction based lateral flow assay provides a versatile, flexible, convenient, and cost-effective technique for visual detection of targets of interest.