Liu Yang, Yu Xiao, Zhao Rui, Shangguan Di-Hua, Bo Zuyi, Liu Guoquan
Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China.
Biosens Bioelectron. 2003 Oct 1;18(11):1419-27. doi: 10.1016/s0956-5663(03)00090-3.
Quartz crystal microbalance (QCM) biosensor integrated in a flow injection analysis (FIA) system was used for the investigation of the specific interaction between immunoglobin G (IgG) and histidine. The histidine was immobilized on the gold electrodes of the piezoelectric crystal using appropriate procedures based on self-assembling of the dithiothreitol (DTT). The specific interaction of the immobilized ligand with IgG in solution was followed as a change in the resonant frequency of the modified crystal and studied in real time without any additional labels. With the mass sensitive biosensor system, the differences in affinity of three different species of IgG: human IgG, goat IgG and mouse IgG were easily distinguished and their respective kinetic rate constants (kass and kdiss) and equilibrium association constants (KA) were determined from the curves of frequency versus time. For the interactions, KA were 2.92 x 10(4), 3.23 x 10(4) and 4.08 x 10(4) M(-1) for human IgG, goat IgG and mouse IgG, respectively.
集成在流动注射分析（FIA）系统中的石英晶体微天平（QCM）生物传感器用于研究免疫球蛋白G（IgG）与组氨酸之间的特异性相互作用。基于二硫苏糖醇（DTT）的自组装，采用适当程序将组氨酸固定在压电晶体的金电极上。固定化配体与溶液中IgG的特异性相互作用通过修饰晶体共振频率的变化来跟踪，并在无任何额外标记的情况下进行实时研究。利用质量敏感生物传感器系统，可轻松区分三种不同种类IgG（人IgG、山羊IgG和小鼠IgG）的亲和力差异，并从频率随时间变化的曲线中确定它们各自的动力学速率常数（kass和kdiss）以及平衡缔合常数（KA）。对于这些相互作用，人IgG、山羊IgG和小鼠IgG的KA分别为2.92×10⁴、3.23×10⁴和4.08×10⁴ M⁻¹。
