Development of new strategies in photoelectrochemical (PEC) sensors is an important way to realize sensitive detection of biomolecule. In this study, mesoporous silica nanospheres (MSNs)-assisted split-type PEC aptasensor with in situ generation of Bi₂S₃ was proposed to achieve reliable detection of prostate-specific antigen (PSA). To be more specific, this bioresponsive release system will release large amounts of Na₂S by the reaction between PSA and aptamer that capped Na₂S-loading MSNs. Next, the Na₂S reacts with Bi to yield BiOI/BiOBr/Bi₂S₃ composite, which leads to an alteration in the electron-hole transfer pathway of the photoelectric material and a decrease in the response. As the PSA concentration increases, more Na₂S can be released and lower photocurrent is obtained. The linear range under the optimal experimental conditions is 10 pg·mL⁻¹-1 μg⋅mL⁻¹, and the detection limit is 1.23 pg⋅mL⁻¹, which has satisfactory stability and anti-interference.

开发光电化学（PEC）传感器新策略是实现生物分子灵敏检测的重要途径。在这项研究中，提出了介孔二氧化硅纳米球（MSN）辅助的分裂型PEC适体传感器原位生成Bi ₂ S _{3以实现前列腺特异性抗原（PSA）的可靠检测。更具体地说，这种生物响应性释放系统将通过PSA与负载Na 2} S的MSN的适体之间的反应释放大量的Na _{2 S。}接下来，Na ₂ S与Bi反应生成BiOI/BiOBr/Bi ₂ S ₃复合材料，这导致光电材料的电子-空穴传输路径的改变和响应的降低。随着PSA浓度的增加，可以释放更多的Na _{2 S并获得更低的光电流。}最佳实验条件下线性范围为10 pg·mL ⁻¹ -1 μg·mL ⁻¹，检出限为1.23 pg·mL ⁻¹，具有良好的稳定性和抗干扰性。