Recently, Prof. Zhang Min and postdoctoral Ma shenhui of our research group published an article entitled “tetrahedral dnanostructure based biosensor for high performance detection of circulating tumor dnausingall carbonanotu beta transmitter” on biosensors and bio electronics, an international well-known journal in the field of biosensors. The research results were completed by the research team of Prof. Zhang Min and the research team of Professor Li Zigang / researcher Yin Feng of the school of chemical biology and biotechnology, with postdoctoral Ma feihui and postdoctoral Zhang Yaping of the school of chemical biology and biotechnology as the co first authors. In this work, a new biosensor based on DNA origami technology and all carbon nanotube thin film transistor was realized, and its application in blood circulation tumor DNA detection was studied.
Adopting carbon nanotube (CNT) transistors as biosensors has been developed as a promising method for cancer biomarker detection, which has shown superior sensitivity and selectivity. However, the detection of circulating tumor DNA (ctDNA) by the CNT transistor based biosensors is still a challenge and no work has been reported. Here, direct label-free DNA detection of AKT2 gene related to triple-negative breast cancer by all-CNT thin-film transistor (TFT) biosensors incorporated with tetrahedral DNA nanostructures (TDNs) is proposed and achieved for the first time. The adoption of TDNs enables improved biosensor response for at least 35% and even as high as 98% as compared with single-stranded DNA (ssDNA) probes owing to the enhanced DNA hybridization efficiency. Influence of the TDNs’ linker length on the biosensor performance is important and has been investigated. Concentration-dependent DNA detection is achieved by the all-CNT TFT biosensors with a broad linear detection range of six orders of magnitude and a theoretical limit of detection (LOD) of 2fM. In addition, the all-CNT TFT biosensors exhibit favorable selectivity and repeatability. The platform of all-CNT TFT biosensors incorporated with TDNs has great potential for multiplexed detection of various cancer biomarkers, providing a simple yet high performance universal strategy for low-cost clinical applications.