表面等离子共振技术测定药物与人血清白蛋白的相互作用

目的应用表面等离子共振技术(SPR)建立一种新的测定白蛋白与化合物相互作用的方法。方法将人血清白蛋白(HSA)固定在CM5芯片表面。不同化合物的溶液流经固定于芯片表面的HSA,SPR显示在芯片表面的折射系数变化。分析软件处理数据,用HSA流通池得到的数据减去参比池得到的数据进行拟合,确定结合常数。结果所有测试药物与固定的HSA可逆结合。紫草素1的平衡结合常数KA为3000L.mol-1。SPR样品需要量最小而且能够自动分析,还可以直接检测小分子(Mr308~585)结合,使之适用于评价药物与HSA相互作用。结论HSA主要的药物键合位点没有因为被固定到芯片表面而破坏。验证了SPR可以准确简易测定化合物的结合解离。

Interactions between drug and human serum albumin investigated using surface plasmon resonance technology

AIM The interactions between a set of drugs and immobilized human serum albumin (HSA) were investigated using surface plasmon resonance (SPR) technology. METHODS HSA was immobilized to the sensor chip, using carbodiimide coupling. The compounds were injected across the sensor surface. The SPR reflects changes in refractive index at the sensor surface. Data obtained in the reference flowcell was subtracted from that obtained in the HSA flowcell. Biaevaluation software analyzes the data to get the affinity
constant. RESULTS All compound tested bound reversibly to immobilize HSA. The affinity constant of shikonin 1 is 3000 L·mol^-1. The ability to examine directly the binding of small molecules(M_r 308-585), coupled with minimal sample requirements and automated instrumentation, makes BIAcore technology applicable for evaluating drug/HSA interactions. CONCLUSION Major HSA binding sites are available after immobilization. These results validate the biosensor technology and illustrate how BIAcore can be used to study drug/HSA interactions in a high resolution mode.