基于溶胶-凝胶技术可更新的安培分析免疫传感器用于人血清中补体3的测定

Renewable Amperometric Immunosensor Based on Sol-Gel Technique for Complement 3 Assay

在低温下 ,通过混合石墨粉、补体 3抗血清、溶胶 -凝胶而制备了一种基于溶胶 -凝胶技术的可更新的安培分析免疫传感器。该传感器坚固、多孔 ,拥有一个可更新的表面 ,在辣根过氧化物酶标记的补体 3的协助下 ,通过竞争性的免疫分析来确定人血清中补体 3的含量。以邻 -氨基酚作为底物 ,- 1 5 0 m V作为工作电位 ,响应电流与补体 3的浓度在 1 .1 7～ 35 .1 μg/m L范围内呈线性关系 ,检出限为 0 .5 6μg/m L。

A renewable amperometric immunosensor based on sol gel technique has been constructed by dispersing graphite, complement 3(C 3) antiserum and sol gel at low temperature. The prepared immunosensor is rigid, porous, and has a renewable external surface. A competitive binding assay has been used to determine C 3 in human serum with the aid of C 3 labeled with horseradish peroxidase. The enzyme labeled antigen can readily diffuse toward the encapsulated antibody, which retains its binding properties. The experimental parameters of the assay with the biocomposite, including the loading of C 3 antiserum in the biocomposite, the amount of labeled C 3 in incubation solution, incubation time and temperature, have been optimized. Using C 3 labeled with horseradish peroxidase, and o AP as the substrate, an amperometric detection at -150 mV (vs. SCE) results in a linear detection range of 1.17~35.1 μg/mL, with a detection limit of 0.56 μg/mL. Serum samples have been assayed and the results demonstrate the feasibility of the proposed immunosensor for clinical analysis. The surface of the immunosensor can be renewed by simple polishing to obtain a fresh immunocomposite ready to use in a new competitive assay.