提出了一种结合光电化学(PEC)和电化学(EC)的生物功能免疫传感器,用于定量检测人体血液中的肝癌标志物甲胎蛋白(AFP)。首先在导电玻璃FTO上制备了BiVO4/BiOI-MWCNTs光活性材料,光电极被壳聚糖和戊二醛功能化。然后,AFP捕获抗体(Ab1)在光电电极上成功修饰,PEC实现了AFP抗原的无标记快速检测。此外,Au@PdPt纳米球也用作与AFP检测抗体(Ab2)结合的标记物。由于Au@PdPt在EC反应中具有优异的催化性能,当Ab2与AFP抗原结合时,可以实现EC应答的信号增加,这确保了AFP检测的高灵敏度。PEC和EC的检出限分别为0.050pg/mL和0.014pg/mL,分别。该传感器还具有良好的特异性,稳定性和重现性,在临床样品的检测中表现出优异的性能,具有良好的临床适用性。
A biofunctional immunosensor combining photoelectrochemical (PEC) and electrochemical (EC) was proposed for the quantitative detection of the liver cancer marker alpha-fetoprotein (AFP) in human blood. BiVO4/BiOI-MWCNTs photoactive materials were first prepared on conductive glass FTO, and the photoelectrode was functionalized by chitosan and glutaraldehyde. Then, the AFP capture antibody (Ab1) was successfully modified on the photoelectrode, and the label-free rapid detection of AFP antigen was achieved by PEC. In addition, Au@PdPt nanospheres were also used as a marker for binding to AFP detection antibody (Ab2). Due to the excellent catalytic properties of Au@PdPt in EC reaction, a signal increase in the EC response can be achieved when Ab2 binds to the AFP antigen, which ensures high sensitivity for the detection of AFP. The detection limits of PEC and EC are 0.050 pg/mL and 0.014 pg/mL, respectively. The sensor also possesses good specificity, stability and reproducibility, shows excellent performance in the detection of clinical samples and has good clinical applicability.