A transistor array biosensor based on reduced graphene oxide prepared electrochemically for detection of multiplex circulating miRNAs of non-small cell lung cancer in human serum

Abstract

The early diagnostic of non-small cell lung cancer (NSCLC) at an early stage can improve patient prognosis and patient survival rates. Here, a novel transistor-based array biosensor was developed for the multiplex detection of four miRNAs (miRNA 21, miRNA 486–5p, miRNA 155, and miRNA 205) as circulating miRNA biomarkers in NSCLC. The transistor channel was modified by a reduced graphene oxide (rGO) semiconductor layer that was prepared based on electrochemical reduction of graphene oxide (GO) through optimal condition. The rGO transistor exhibited excellent transistor performance and high stability, which provided enough guarantee for stable detection of biomarkers. Further, PAA/PEDOT film was modified on the surface of rGO layer in channel to improve selectivity, enhance signal response and provide coupling group. The capture DNA was coupled on the surface of PAA/PEDOT film to obtain H/PAA/PEDOT/rGO transistor, then the Y-shape nucleic acid structure was specifically designed to capture target miRNA. Finally, the H/PAA/PEDOT/rGO transistor array biosensor exhibited an excellent linearity for four miRNAs (miRNA 21, miRNA 486–5p, miRNA 155, and miRNA 205), with low detection limit 2.36 fM, had high selectivity, sensitivity and stability. Moreover, the biosensor also had reusability performance, which lowered the cost of biosensor and improved the feasibility of industrialization. These studies indicated that the novel H/PAA/PEDOT/rGO transistor biosensor array would have great promise for applications in early blood diagnosis and postoperative monitoring of NSCLC.