A Dual-Mode Radio Frequency DNA Sensor

Different from traditional detection methods which were expensive and time consuming for biochemical analyses, a DNA chip assay by using gold nanoparticles (AuNPs) immunological amplification methods and radio frequency techniques was applied to detect DNA sequences rapidly and conveniently. First the capture DNA (cDNA) was immobilized to the substrate on which the LC shunt located. Then the target DNA (tDNA) and probe DNA (pDNA) with AuNP at the 3´ end were added to form AuNP-linking structures. Furthermore, the S11 and S21 curves of the biosensors changed due to the AuNP-linking structures between the interdigital and meander waveguides. The changes in S11 and S21 determined whether the tDNA existed. Due to the dual-mode design of the DNA sensors, this platform has a potential for multi-sample detection. The study provided an alternatively simple, fast and convenient solution for biochemical detection.