Okhai Timothy A, Mokwebo Kefilwe V, Oranzie Marlon, Feleni Usisipho, Snyman Lukas W
Clinical Engineering Group, Department of Electrical Engineering, Faculty of Engineering and the Built Environment, Tshwane University of Technology, Pretoria 0183, South Africa.
Department of Electrical Engineering, College of Science, Engineering and Technology, University of South Africa, Florida Campus, Johannesburg 1710, South Africa.
Biosensors (Basel). 2025 Jul 3;15(7):428. doi: 10.3390/bios15070428.
An electrochemical immunosensor for the quantification of prostate-specific antigens (PSAs) using silver nanocrystals (AgNCs) is reported. The silver nanocrystals were synthesized using a conventional citrate reduction protocol. The silver nanocrystals were characterized using scanning electron microscopy (SEM) and field effect scanning electron microscopy (FESEM), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), Fourier-transform infrared spectroscopy (FTIR), UV-Vis spectroscopy, and small-angle X-ray scattering (SAXS). The proposed immunosensor was fabricated on a glassy carbon electrode (GCE), sequentially, by drop-coating AgNCs, the electro-deposition of EDC-NHS, the immobilization of anti-PSA antibody (Ab), and dropping of bovine serum albumin (BSA) to prevent non-specific binding sites. Each stage of the fabrication process was characterized by cyclic voltammetry (CV). Using square wave voltammetry (SWV), the proposed immunosensor displayed high sensitivity in detecting PSA over a concentration range of 1 to 10 ng/mL with a detection limit of 1.14 ng/mL and R of 0.99%. The immunosensor was selective in the presence of interfering substances like glucose, urea, L-cysteine, and alpha-methylacyl-CoA racemase (AMACR) and it showed good stability and repeatability. These results compare favourably with some previously reported results on similar or related technologies for PSA detection.
报道了一种使用银纳米晶体（AgNCs）定量检测前列腺特异性抗原（PSA）的电化学免疫传感器。采用传统的柠檬酸盐还原法合成银纳米晶体。通过扫描电子显微镜（SEM）、场效应扫描电子显微镜（FESEM）、X射线衍射（XRD）、高分辨率透射电子显微镜（HRTEM）、傅里叶变换红外光谱（FTIR）、紫外可见光谱和小角X射线散射（SAXS）对银纳米晶体进行了表征。所提出的免疫传感器依次通过滴涂AgNCs、电沉积EDC-NHS、固定抗PSA抗体（Ab）以及滴加牛血清白蛋白（BSA）以防止非特异性结合位点，制备在玻碳电极（GCE）上。制备过程的每个阶段都通过循环伏安法（CV）进行了表征。使用方波伏安法（SWV），所提出的免疫传感器在1至10 ng/mL的浓度范围内检测PSA时显示出高灵敏度，检测限为1.14 ng/mL，相关系数R为0.99%。该免疫传感器在存在葡萄糖、尿素、L-半胱氨酸和α-甲基乙酰辅酶A消旋酶（AMACR）等干扰物质的情况下具有选择性，并且显示出良好的稳定性和重复性。这些结果与先前报道的一些关于PSA检测的类似或相关技术的结果相比具有优势。
