。开发了一种基于 ZnO/聚（5-甲酰基吲哚）（P5FIn）/花青素异质结构的夹心型光电化学 (PEC) 免疫传感器，以实现肿瘤标志物 CYFRA21-1 的灵敏无背景检测。具有良好光伏性能的ZnO与窄带隙P5FIn结合形成p-n型异质结。这种结构减少了电子空穴对复合，从而增强了复合材料的光电流响应。花青素是一种环境友好的天然化合物，具有优异的抗氧化、氧化还原性能和显着的电化学活性。经过花青素敏化后，复合材料对可见光的吸收和利用增强，进一步提高了材料的PEC发光效率。此外，氮化硼量子点 (BN QD) 通过聚多巴胺 (PDA) 与 Ab2 结合作为二抗标记物，增强了其灵敏度。该生物传感器的线性检测范围为 0.001-100 ng mL-1，检测限 (LOD) 为 0.00033 ng mL-1。此外，该生物传感器表现出出色的选择性、重现性和稳定性，以及在分析实际人血清样本方面的成功结果。该方法为肿瘤标志物检测提供了一种可行的方法。© 2024。作者获得 Springer-Verlag GmbH Austria（Springer Nature 旗下公司）的独家许可。

. A sandwich-type photoelectrochemical (PEC) immunosensor based on a ZnO/poly(5-formylindole) (P5FIn)/anthocyanin heterostructure was developed to achieve sensitive background-free detection of the tumor marker CYFRA21-1. ZnO with good photovoltaic properties is combined with narrow bandgap P5FIn to form a p-n type heterojunction. This structure reduces the electron-hole pair recombination, thereby enhancing the photocurrent response of the composite. Anthocyanidins are environmentally friendly natural compounds with excellent antioxidant, redox properties, and remarkable electrochemical activity. After sensitization by anthocyanins, the absorption and utilization of visible light in the composites are enhanced, further improving the PEC luminescence efficiency of the materials. Additionally, boron nitride quantum dots (BN QDs) are combined with Ab2 via polydopamine (PDA) as a secondary antibody marker, enhancing its sensitivity. The biosensor exhibited a linear detection range of 0.001-100 ng mL-1 with a limit of detection (LOD) of 0.00033 ng mL-1. Furthermore, this biosensor demonstrates excellent selectivity, reproducibility, and stability, as well as successful results in analyzing actual human serum samples. This approach provides a feasible method for tumor marker detection.© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.