采用溶剂热法,通过有机单体合成了一种亚胺键连接的共价有机框架材料(COF-LZU1);在常温常压条件下,通过后合成的方法将贵金属钯(Ⅱ)引入到COF材料中,合成了复合材料Pd/COF-LZU1,该材料具有优良的催化性能.利用Pd/COF-LZU1多孔复合材料将C-反应蛋白(CRP)抗体(anti-CRP)固定在玻碳电极表面,构建了一种非标记型CRP免疫传感器.当抗体与抗原发生免疫反应时,形成的免疫复合物会阻碍电化学探针[Fe(CN)6]^4-/3-的电子传递,降低其响应电流,从而实现CRP的快速检测.采用交流阻抗和差示脉冲伏安法(DPV)考察了免疫传感器的电化学特性,同时考察了测试底液的p H值、抗原培育时间和抗体固定浓度等实验条件对传感器性能的影响.在最优的实验条件下,采用DPV法对CRP进行检测的线性范围为5-180 ng/m L,检出限为1.66 ng/m L,线性相关系数为0.992.
A new imine-linked covalent organic framework( COF) material was synthesized using organic monomer via solvothermal methods. Pd( Ⅱ)-coordinated COF,Pd / COF-LZU1,was accordingly synthesized through simple post-treatment at ambient conditions,which showed excellent catalytic activity. Then,a labelfree C-reactive protein( CRP) immunosensor was constructed using the Pd / COF-LZUI porous composite material to immobilize anti-CRP on the surface of GCE. When anti-CRP binds with CRP antigen,the formed immuno complex obstruct the electric signal of Fe( CN)6^4-/3-,which can be used to realize label-free detection of CRP. Electrochemical impedence spectroscopy( EIS) and differential pulse voltammetry( DPV) were employed to characterize the immunosensor. The experimental conditions such as scanning rate,p H value of testing solution,the concentration of anti-CRP and incubation time were also optimized. Under the optimal experimental conditions,the linear range was 5—180 ng / m L,the detection limit was 1. 66 ng / m L,with the linear correlation coefficient of 0. 992. This immunosensor provides a novel and simple way to detect CRP,and develops the application of the COFs in the electrochemical immunosensor.