A novel and sensitive RF magnetron sputtered tin oxide (SnO₂) thin film based breast cancer immunosensor that combines exquisite sensitivity, rapid determination and specificity with a simple, inexpensive and easy-to-use technology has been realized. A SnO₂ thin film based biocompatible matrix has been used for immobilization of breast cancer specific antibody CA 15-3 by a physical adsorption technique for an efficient detection of breast cancer antigen CA 15-3. The fabricated immunoelectrode (antibody CA 15-3 (Ab)/SnO₂/Pt/Ti/glass) has been characterized using scanning electron microscopy (SEM), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The optimal equivalent circuit model that matches the impedimetric responses of the immunoelectrode describes three distinct regions: the electrolyte solution resistance (R_s), the double layer capacitance (C_dl) and the specific charge transfer resistance (R_ct). The SnO₂ thin film based immunosensor produces a decrease in the peak oxidation current in CV and DPV studies due to the steric hindrance caused by the macromolecular antibody. The immunoelectrode (Ab/SnO₂/Pt/Ti/glass) exhibits a linear increase in electrochemical impedance response upon combining with the specific antigen CA 15-3, in a wide range of antigen concentration from 50 ng dL⁻¹ to 700 ng dL⁻¹ (8 U mL⁻¹ to 120 U mL⁻¹) with a R_ct sensitivity of 38.63 (ng dL⁻¹)⁻¹, fast response time and a high shelf life of more than 20 weeks.

中文翻译：

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使用基于氧化锡薄膜的免疫电极有效检测乳腺癌特异性生物标志物CA 15-3的阻抗反应研究

已经实现了一种新颖且灵敏的RF磁控溅射氧化锡（SnO ₂）薄膜基乳腺癌免疫传感器，其结合了灵敏的灵敏度，快速的测定和特异性以及简单，廉价且易于使用的技术。基于SnO ₂薄膜的生物相容性基质已通过物理吸附技术用于固定乳腺癌特异性抗体CA 15-3，以有效检测乳腺癌抗原CA 15-3。制备的免疫电极（抗体CA 15-3（Ab）/ SnO ₂/ Pt / Ti /玻璃）已使用扫描电子显微镜（SEM），循环伏安法（CV）和电化学阻抗谱（EIS）进行了表征。与免疫电极的阻抗响应匹配的最佳等效电路模型描述了三个不同的区域：电解质溶液电阻（R _s），双层电容（C _dl）和比电荷转移电阻（R _ct）。基于大分子抗体的空间位阻，基于SnO ₂薄膜的免疫传感器在CV和DPV研究中产生峰值氧化电流降低。免疫电极（Ab / SnO ₂/铂/钛/玻璃）表现出电化学阻抗响应在与特定抗原CA 15-3从50纳克dL的组合，在范围广泛的抗原浓度的线性增加^-1到700纳克dL的^-1（8毫升Ü ^{- 1}至120单位毫升^-1）与[R _CT的38.63灵敏度（毫微升^-1）^-1，快速响应时间和的20周以上高的保质期。