Wang J, Pamidi P V, Rogers K R
Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces 88003, USA.
Anal Chem. 1998 Mar 15;70(6):1171-5. doi: 10.1021/ac971093e.
Sol-gel processing is used for the first time for the preparation of electrochemical immunosensors. One-step sensor fabrication, based on the coupling of sol-gel and screen-printing technologies, is employed. A low-temperature cured ink is prepared by dispersion of rabbit immunoglobulin G (RIgG), graphite powder, and a binder in the sol-gel solution. The enzyme-labeled antibody can readily diffuse toward the encapsulated antigen, which retains its binding properties, and the association reaction is easily detected at the dispersed graphite surface. Use of anti-RIgG labeled with alkaline phosphatase, naphthyl phosphate as the substrate, and amperometric detection at +400 mV (vs Ag/AgCl) results in a low detection limit of 5 ng/mL (32 pM) for the solution antigen. Tailoring the porosity of the ceramic-carbon matrix can be used for tuning the assay performance. The high sensitivity, low cost, durability, and simplicity of the new single-use immunosensors make them well suited for various on-site applications.
溶胶-凝胶工艺首次用于制备电化学免疫传感器。采用了基于溶胶-凝胶和丝网印刷技术相结合的一步法传感器制造工艺。通过将兔免疫球蛋白G（RIgG）、石墨粉和粘合剂分散在溶胶-凝胶溶液中制备低温固化油墨。酶标记抗体能够很容易地向包封的抗原扩散，抗原保留其结合特性，并且在分散的石墨表面很容易检测到缔合反应。使用碱性磷酸酶标记的抗RIgG、萘基磷酸作为底物，并在+400 mV（相对于Ag/AgCl）下进行安培检测，溶液抗原的检测限低至5 ng/mL（32 pM）。调整陶瓷-碳基质的孔隙率可用于调节检测性能。新型一次性免疫传感器的高灵敏度、低成本、耐用性和简易性使其非常适合各种现场应用。
