Li Lihua, Zhang Wenzhi, Wei Yan, Yu Lizhen, Feng Dexiang
Department of Pharmacy, Wannan Medical College, Wuhu 241002, China.
Institute of Synthesis and Application of Medical Materials, Department of Chemistry, Wannan Medical College, Wuhu 241002, China.
J Anal Methods Chem. 2022 Jul 20;2022:6209731. doi: 10.1155/2022/6209731. eCollection 2022.
A simple, sensitive, and fluorescent immunoassay for the detection of prostate-specific antigen (PSA) based on horseradish peroxidase and silicon dioxide nanospheres as a signal amplification strategy has been described. In the design, the primary antibody (Ab) of PSA was first immobilized on the 96-well plates via physical adsorption between polystyrene and hydrophobic groups of the antibody molecule. The silicon dioxide nanospheres (SiO NSs), with large surface area and good biocompatibility, were loaded with horseradish peroxidase (HRP) and horseradish peroxidase-labeled secondary antibodies (HRP-Ab) as signal amplification systems. In the presence of PSA, a sandwich-type immunocomplex composed of Ab-Ag-HRP-Ab had been formed. Fluorescence technology was employed to obtain the response signal of the immunoassay in the -tyrosine and HO systems. Experiment results showed that a strong and stable fluorescent signal at 416 nm (excitation wavelength: 325 nm) was observed, and the changes in fluorescent intensity were related to the levels of PSA. Under the optimal conditions, the relative fluorescence intensity was linear with the logarithm of PSA concentration from 0.03 to 100 ng·mL, with a detection limit of 0.01 ng·mL (at a signal/noise ratio of 3). In contrast to other fluorescent immunoassays, the sandwich-type immunoreaction based on the high binding ELISA plates has the advantages of being simple, stable, and easy to operate, high selectivity, small sample quantity, etc., which can be widely used in the selective detection of a variety of targets, from DNA to proteins and small molecules. Such fluorescent immunoassays should be feasible for the fields of molecular diagnosis and other life science fields in the future.
本文描述了一种基于辣根过氧化物酶和二氧化硅纳米球作为信号放大策略的简单、灵敏的荧光免疫分析法，用于检测前列腺特异性抗原（PSA）。在该设计中，PSA的一抗首先通过抗体分子的疏水基团与聚苯乙烯之间的物理吸附固定在96孔板上。具有大表面积和良好生物相容性的二氧化硅纳米球（SiO NSs）负载辣根过氧化物酶（HRP）和辣根过氧化物酶标记的二抗（HRP-Ab）作为信号放大系统。在PSA存在的情况下，形成了由Ab-Ag-HRP-Ab组成的夹心型免疫复合物。采用荧光技术在-酪氨酸和HO系统中获得免疫分析的响应信号。实验结果表明，在416nm（激发波长：325nm）处观察到强而稳定的荧光信号，荧光强度的变化与PSA水平相关。在最佳条件下，相对荧光强度与PSA浓度的对数在0.03至100 ng·mL范围内呈线性关系，检测限为0.01 ng·mL（信噪比为3）。与其他荧光免疫分析方法相比，基于高结合ELISA板的夹心型免疫反应具有简单、稳定、易于操作、选择性高、样品用量少等优点，可广泛用于从DNA到蛋白质和小分子等多种靶标的选择性检测。这种荧光免疫分析方法在未来的分子诊断和其他生命科学领域应该是可行的。
