The sensitive and label-free detection of multiple biomarkers on a single electrode by photoelectrochemical (PEC) sensors based on light addressing strategies is very attractive for developing portable and high-throughput biosensing systems. The essential prerequisite of this proposal is the employment of uniform photovoltaic material modified electrodes with high conversion efficiency. Herein, a novel two-step constant potential deposition method for the rapid fabrication of bismuth sulfide film modified ITO electrodes (Bi₂S₃/ITO) was established. The produced Bi₂S₃/ITO, with excellent uniformity and high conversion efficiency in visible light ranges, was further modified with gold nanoparticles (AuNPs) and then divided into separated identical sensing zones by insulative paints. The adsorption-based immobilization of antibodies of three tumor markers, i.e., a-fetoprotein (AFP), carcinoembryonic antigen (CEA) and cancer antigen 19-9 (CA19-9), onto different sensing zones of the electrode and the further blocking with BSA established a label-free and light-addressable PEC sensor (LF-LAPECS), which can achieve the rapid and sensitive detection of these biomarkers with wide linear ranges, low detection limits and self-calibration ability. Moreover, the detection throughput can be conveniently improved by enlarging the size of the substrate electrode and increasing the number of separated sensing zones. The present work thus demonstrates the promising applications of PEC techniques for developing sensitive, time-saving, cost-effective and high-throughput biosensing methods.

中文翻译：

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在单个光寻址光电化学传感器上对多种肿瘤标记物进行无标记的高通量生物传感

基于光寻址策略的光电化学（PEC）传感器对单个电极上的多个生物标记物进行灵敏且无标签的检测，对于开发便携式和高通量生物传感系统非常有吸引力。该提议的基本前提是采用具有高转换效率的均一的光伏材料改性电极。在此，建立了一种新颖的两步恒电位沉积方法，用于快速制备硫化铋薄膜修饰的ITO电极（Bi ₂ S ₃ / ITO）。生产的Bi ₂ S ₃ITO / ITO在可见光范围内具有出色的均匀性和高转换效率，可通过金纳米颗粒（AuNP）进行进一步修饰，然后通过绝缘涂料将其分成单独的相同传感区域。三种肿瘤标记物，即甲胎蛋白（AFP），癌胚抗原（CEA）和癌抗原19-9（CA19-9）的吸附吸附固定在电极的不同感应区上，并进一步阻断BSA建立了无标签光寻址PEC传感器（LF-LAPECS），该传感器可实现线性范围宽，检测限低和自校准能力强的这些生物标志物的快速灵敏检测。此外，可以通过增大基板电极的尺寸并增加分离的感测区的数量来方便地提高检测吞吐量。