In this paper the field-effect transistor DNA biosensor for detecting hepatitis B virus (HBV) based on indium tin oxide nanowires (ITO NWs) in label free approach has been fabricated. Because of ITO nanowires intensive conductance and functional modified surface, the probe immobilization and target hybridization were increased strongly. The high resolution transmission electron microscopy (HRTEM) measurement showed that ITO nanowires were crystalline and less than 50 nm in diameter. The single-stranded hepatitis B virus DNA (SS-DNA) was immobilized as probe on the Au-modified nanowires. The DNA targets were measured in a linear concentration range from 1fM to 10 µM. The detection limit of the DNA biosensor was about 1fM. The time of the hybridization process for defined single strand was 90 min. The switching ratio of the biosensor between "on" and "off" state was ~ 1.1 × 10⁵. For sensing the specificity of the biosensor, non-complementary, mismatch and complementary DNA oligonucleotide sequences were clearly discriminated. The HBV biosensor confirmed the highly satisfied specificity for differentiating complementary sequences from non-complementary and the mismatch oligonucleotides. The response time of the DNA sensor was 37 s with a high reproducibility. The stability and repeatability of the DNA biosensor showed that the peak current of the biosensor retained 98% and 96% of its initial response for measurements after three and five weeks, respectively.

本文制备了一种基于铟锡氧化物纳米线（ITO NWs）的无标记法检测乙型肝炎病毒（HBV）的场效应晶体管DNA生物传感器。由于ITO纳米线具有高传导性和功能性修饰的表面，因此大大提高了探针固定和靶标杂交的能力。高分辨率透射电子显微镜（HRTEM）测量表明，ITO纳米线是晶体，直径小于50 nm。将单链乙型肝炎病毒DNA（SS-DNA）固定为Au修饰的纳米线上的探针。DNA靶标的线性浓度范围为1fM至10 µM。DNA生物传感器的检出限约为1fM。限定的单链的杂交过程时间为90分钟。生物传感器在“⁵。为了感测生物传感器的特异性，明显区分了非互补的，错配的和互补的DNA寡核苷酸序列。HBV生物传感器证实了将互补序列与非互补和错配寡核苷酸区分开来的高度满意的特异性。DNA传感器的响应时间为37 s，重复性很高。DNA生物传感器的稳定性和可重复性表明，生物传感器的峰值电流分别在三周和五周后保持了其初始响应的98％和96％。