Ferreira Antonio Aparecido Pupim, Colli Walter, da Costa Paulo Inácio, Yamanaka Hideko
Instituto de Química, UNESP, R. Prof. Francisco Degni, s/n, 14800-900 Araraquara, SP, Brazil.
Biosens Bioelectron. 2005 Jul 15;21(1):175-81. doi: 10.1016/j.bios.2004.08.001.
Trypanosoma cruzi proteins from epimastigote membranes, herein referred as antigens, have been used for the construction of an amperometric immunosensor for serological diagnosis of Chagas' disease. The proteins used had a molecular mass ranging from 30 to 100 kDa. The gold electrode was treated with cysteamine and glutaraldehyde prior to antigen immobilization. Antibodies present in the serum of patients with Chagas' disease were captured by the immobilized antigens and the affinity interaction was monitored by chronoamperometry at a potential of -400 mV (versus Ag pseudo-reference electrode) using peroxidase-labeled IgG conjugate and hydrogen peroxide, iodide substrate. The incubation time to allow maximum antigen-antibody and antibody-peroxidase-labeled IgG interactions was 20 min with a reactivity threshold at -0.104 microA.
来自锥鞭毛体膜的克氏锥虫蛋白（本文称为抗原）已用于构建用于恰加斯病血清学诊断的安培免疫传感器。所使用的蛋白质分子量范围为30至100 kDa。在固定抗原之前，金电极先用半胱胺和戊二醛处理。恰加斯病患者血清中的抗体被固定的抗原捕获，并使用过氧化物酶标记的IgG缀合物和过氧化氢、碘化物底物，在-400 mV（相对于银伪参比电极）的电位下通过计时电流法监测亲和相互作用。使抗原-抗体和抗体-过氧化物酶标记的IgG相互作用达到最大值的孵育时间为20分钟，反应阈值为-0.104微安。
