基于纳米二氧化钛为载体的新型荧光免疫流动体系测定补体3

Fluoroimmunosensing system for complement 3 detection using nano-titanium dioxide as carrier

研制了一种新的可更新荧光免疫流动体系用于补体3(C_3)的测定。用纳米TiO_2颗粒为固定抗体的载体,辣根过氧化物酶标记C_3(HRP-C_3),以HRP-C_3与待测C_3发生竞争免疫反应。辣根过氧化物酶(HRP)催化荧光底物3,3’5,5’-四甲基联苯胺(TMB)转化为无荧光物质,待测C_3的浓度可由底物溶液的荧光降低值间接测定。通过简单的处理后,固定抗体的载体表面可以得到有效的再生。荧光响应与C_3补体在6.5μg/L到75 μg/L之间呈准线性关系。该方法检测限较低,重复性好,可满足临床检测的要求。

A novel enzyme-link fluoroimmunoassay flow system using 3, 3', 5, 5'-Tetramethyl-benzidine as substrate and nano-titanium dioxide as a carrier of the immobilization of anti- C_3 for the determination of the complement 3(C_3) was developed. HRP-labled complement 3 can catalyze the 3, 3', 5, 5'-Tetramethylbenzidine(TMB) to form a non-fluorescence substance. The concentration of C_3 can be determined by fluorescence decrease of TMB after competitive immunoreactions as nano-titanium dioxide to be support. The fluorescence intensity was measured in PBS containing 2. 5×10^(-7) mmol/L TMB and 5×10^(-7) mmol/L H_2O_2 at pH6.8. The sensor system exhibits a linear response to C_3 in the concentration range 6. 5 μg/L to 75 μg/L, correlation coefficient 0.981. The sensor system was applied to the determination of complement 3 in human serum with satisfactory results.