石英晶体微天平用于日本血吸虫Ag—Ab免疫反应的动力学研究

KINETIC STUDIES OF SJAG-SJAB IMMUNOREACTION USING QUARTZ CRYSTAL MICROBALANCE METHODOLOGY

在镀金电极的压电石英晶体表面形成巯基丙酸（ＭＰＡ）单分子膜，经ＮＨＳ和ＥＤＣ活化后 固定日本血吸虫抗原（ＳｊＡｇ），用石英晶体微天平技术监测ＳｊＡｂ在压电石英晶体上的吸咐与解吸过程， 研究了免疫反应体系ＳｊＡｇ－ＳｊＡｂ在反应动力学。结果表明：ＳｊＡｂ在压电石英晶体上的键合行为很好 地符合 Ｌａｎｇｍｕｉｒ吸附方程，免疫反应的结合常数 Ｋａｓｓ为 ３．４６ ｘ １０^(６)（ｍｏｌ／Ｌ）^(－１)。在抗体过量情况下为 一级反应。计算了日本血吸虫免疫反应的速率常数为Ｋ_(ｆ)为６、３５ ｘ １０^(３)（ｍｏｌ／Ｌ）^(－１)Ｓ^(－１)（２５℃）。

The adsorption and desorption of S. japonicum antibody on the crystal modified with S. japonicum antigen have been continuously monitored and the immunoreaction kinetics of SjAg with SjAb has been investigated by using the quartz crystal microbalance methodology. Immobilization of the SjAg to the crystal 's surface was accomplished via a NHS - EDC - activated copolymer coating of 3 - Mercaptopropionic acid (MPA). the results indicated that the binding behavior of SjAg on the crystals surface was fitted for the Langmuir adsorption equation quite well. The association constant of the immunoreaction(Kass) calculated from this equation was 3.46 ×10^(6)(mol/L) ^(-1) . The Kinenic equation of this reaction under the condition of excessive SjAb was derived. This equation was exactly fitted for the experimental results. The reaction rate constant k, at 25℃ calculated was 6.35 × 10^(3)(mol/L)^(-1). S^(-1).