Yan Liang, Xu Shuai, Xi Fengna
Shanxi Bethune Hospital, Shanxi Academy of Medical Sciences, Tongji Shanxi Hospital, Third Hospital of Shanxi Medical University, Taiyuan 030032, China.
Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
Nanomaterials (Basel). 2022 Oct 28;12(21):3810. doi: 10.3390/nano12213810.
Sensitive detection of prostate-specific antigens (PSA) in serum is essential for the prevention and early treatment of prostate cancer. Simple and disposable electrochemical immunosensors are highly desirable for screening and mobile detection of PSAs in high-risk populations. Here, an electrochemical immunosensor was constructed based on amino-rich nanochannels array-modified patterned, inexpensive, and disposable indium tin oxide (ITO) electrodes, which can be employed for the sensitive detection of PSA. Using an amino-group-containing precursor, a vertically ordered mesoporous silica nanochannel film (VMSF) containing amino groups (NH-VMSF) was rapidly grown on ITO. When NH-VMSF contained template surfactant micelle (SM), the outer surface of NH-VMSF was directionally modified by aldehyde groups, which enabled further covalent immobilization of the recognitive antibody to prepare the immuno-recognitive interface. Owing to the charge-based selective permeability, NH-VMSF can electrostatically adsorb negatively charged redox probes in solution (Fe(CN)). The electrochemical detection of PSA is realized based on the mechanism that the antigen-antibody complex can reduce the diffusion of redox probes in solution to the underlying electrode, leading to the decrease in electrochemical signal. The constructed immunosensor can achieve sensitive detection of PSA in the range from 10 pg/mL to 1 μg/mL with a limit of detection (LOD) of 8.1 pg/mL. Sensitive detection of PSA in human serum was also achieved. The proposed disposable immunosensor based on cheap electrode and nanochannel array is expected to provide a new idea for developing a universal immunosensing platform for sensitive detection of tumor markers.
血清中前列腺特异性抗原（PSA）的灵敏检测对于前列腺癌的预防和早期治疗至关重要。简单且一次性使用的电化学免疫传感器对于高危人群中PSA的筛查和移动检测非常理想。在此，基于富含氨基的纳米通道阵列修饰的图案化、廉价且一次性的氧化铟锡（ITO）电极构建了一种电化学免疫传感器，可用于PSA的灵敏检测。使用含氨基的前驱体，在ITO上快速生长出含氨基的垂直有序介孔二氧化硅纳米通道膜（VMSF）（NH-VMSF）。当NH-VMSF包含模板表面活性剂胶束（SM）时，NH-VMSF的外表面被醛基定向修饰，这使得识别抗体能够进一步共价固定以制备免疫识别界面。由于基于电荷的选择性渗透性，NH-VMSF可以静电吸附溶液中带负电荷的氧化还原探针（Fe(CN)）。基于抗原-抗体复合物可减少氧化还原探针在溶液中向底层电极的扩散这一机制实现了PSA的电化学检测，导致电化学信号降低。构建的免疫传感器能够在10 pg/mL至1 μg/mL范围内实现对PSA的灵敏检测，检测限（LOD）为8.1 pg/mL。还实现了对人血清中PSA的灵敏检测。所提出的基于廉价电极和纳米通道阵列的一次性免疫传感器有望为开发用于灵敏检测肿瘤标志物的通用免疫传感平台提供新思路。
