Gray S P, Billings J A
Clin Chem. 1983 Mar;29(3):447-51.
A novel substrate, albumin complexed with bromphenol blue, has been developed for the assay of human gastric juice pepsin by a kinetic method in the Cobas centrifugal analyzer. The action of pepsin on the complex degrades the albumin and releases the dye. The change in the color of the substrate is a zero-order reaction. Human and porcine pepsin have different Km's with the new substrate. This kinetic method has a throughput of 28 tests in approximately 10 min and good precision (CV = 2.0%). Other advantages are analysis in homogeneous solution (thereby eliminating the need to separate substrate and products), lack of interference from bilirubin or phenol red, and the expression of pepsin activity in IUB enzyme units.
已开发出一种新型底物，即与溴酚蓝络合的白蛋白，用于在Cobas离心分析仪中通过动力学方法测定人胃液中的胃蛋白酶。胃蛋白酶对该络合物的作用会降解白蛋白并释放出染料。底物颜色的变化是零级反应。人和猪胃蛋白酶对新底物具有不同的米氏常数。这种动力学方法在约10分钟内可完成28次检测，且精密度良好（变异系数CV = 2.0%）。其他优点包括在均相溶液中进行分析（从而无需分离底物和产物）、不受胆红素或酚红的干扰，以及以国际生物化学联合会（IUB）酶单位表示胃蛋白酶活性。
