硝苯地平免疫胶体金探针的制备

Preparation of nifedipine immune colloidal gold probe

目的优化硝苯地平药物的免疫胶体金探针的制备条件。方法采用柠檬酸三钠还原法制备胶体金溶液,采用紫外分光光度法在400-700 nm处测定胶体金溶液吸光度,判断胶体金颗粒大小。调整标记胶体金溶液p H、抗体蛋白量以及复溶液等因素,试制试纸条并进行加标验证实验,确定制备免疫胶体金探针的最优条件。结果实验制备胶体金颗粒大小在20-40 nm;最佳制备条件为：单抗标记p H为9.0,单抗标记量为5.0μL,复溶液为0.5 mol/L Tris（p H 9.0,含0.5%Tween20）。经加标实验验证,试纸条的检测灵敏度可以达到设计要求。结论硝苯地平免疫胶体金探针的制备条件优化,可为下一步制作高质量的免疫胶体金试纸条提供技术准备,可应用于对食品中非法添加硝苯地平的快速检测。

Objective To optimize the preparation conditions of immune colloidal gold probe for detection of nifedipine drugs. Methods Colloidal gold solution was prepared by sodium citrate reduction method, and the absorbance of colloidal gold was determined by ultraviolet spectroscopy（UV） at 400-700 nm, so as to observe the size of colloidal gold. By adjustment of the p H value of labeled colloidal gold solution, the amount of antibody protein and the reconstituted solution to determine the optimal conditions for preparing immune colloidal gold probes, test strip was tested and spiked experiment was verified. Results The size of prepared gold particles was 20-40 nm. The best preparation conditions for immune colloidal gold probe were as follows： the p H value of labeled monoclonal antibodies was 9.0, the labeled amount of monoclonal antibodies was 5.0 μg/m L, and complex solution was 0.5 mol/LTris（p H 9.0, containing 0.5% Tween20）. After verification of standard addition recovery experiment, the sensitivity of the test strip could meet the design requirements. Conclusion The optimization of preparation conditions of immune colloidal gold probe for detection of nifedipine can provide technical preparation for making high quality immune colloidal gold strip, which can be applied for rapid detection of nifedipine illegally added in food.