基于金纳米颗粒/碳化氮-金属有机框架材料Cd-MOFs-74的C-反应蛋白免疫传感器的研制

The Preparation of C-reative Protein Immunosensor Based on Gold Nanoparticles/Nitrogen Carbide and Porous Material Cd-MOF-74

基于金纳米颗粒/碳化氮(Au NPs@C3N4)与多孔有机框架材料Cd-MOF-74,构建了一种新的夹心型免疫传感器用于C-反应蛋白(CRP)的定量检测。以导电率强的Au NPs@C3N4材料为基底,固定CRP抗体(anti-CRP),以提高传感器的灵敏度。同时棒状的多孔材料Cd-MOF-74中含有大量的Cd2+,以此作为信号源可以放大检测信号,进一步提高传感器的灵敏度。使用构建的免疫传感器,采用差分脉冲伏安法(DPV)于0.01 mol/L磷酸盐缓冲溶液(pH=7.4)中检测Cd2+的信号,可实现CRP的定量检测。当CRP含量在0.1~100 ng/mL之间,响应电流强度随CRP抗原浓度的增大而呈线性增高。该夹心型免疫传感器选择性好,灵敏度高,检出限(S/N=3)低至33.3 pg/mL,同标准试剂盒相比检测下限降低了3个数量级。构建的免疫传感器在与CRP相关的疾病监测应用中显示出应用前景。

In this work,a novel sandwich immunosensor based on gold nanoparticles/nitrogen carbide(Au NPs@C3N4)and porous material Cd-MOF-74 was constructed for the quantitative detection of C-reactive proteinprotein.Au NPs@C3N4with high electron mobility was used as conductive substrates to immobilize CRP antibody(anti-CRP),which could enhance the sensitivity of biosensor.The Cd2+in the rod-shaped porous material Cd-MOF-74 was employed as the signal source.Au NPs@Cd-MOF-74 as a signal label could be directly detected without acid treatment.Differential pulse voltammetry(DPV)was used to detect the signal of Cd2+from MOFs in PBS(0.01 mol/L,pH=7.4).When the concentrations of CRP ranged from 0.1 to 100 ng/mL,the response current intensity enhanced with the increase of concentration of CRP.The electrochemical immunosensor exhibited high selectivity and sensitivity,with the detection limit of 33.33 pg/mL(S/N=3).Compared with the standard kit,the sensitivity was improved by 3 orders of magnitude.The immunosensor showed great potential in the application of CRP related disease monitoring.