Schreiber R W, Letavic M A, McGahan T J, White H B
Department of Chemistry and Biochemistry, University of Delaware, Newark 19716.
Anal Biochem. 1991 Feb 1;192(2):392-7. doi: 10.1016/0003-2697(91)90554-7.
Endogenous ligands complicate radioligand-binding assays of high-affinity binding proteins by obscuring binding sites or by diluting the labeled ligand. We have developed a mathematical model for such systems where radioligand and endogenous ligand are structurally identical. Data which relate radioligand binding at equilibrium as a function of sample volume can be plotted such that the concentrations of endogenous ligand and binder are graphically determined; however, a more precise determination may be done by nonlinear regression with the aid of a microcomputer. The method is demonstrated for the assay of biotin-binding proteins in the presence of a range of endogenous biotin concentrations below and above that required to saturate the binding sites.
内源性配体会使高亲和力结合蛋白的放射性配体结合分析变得复杂，因为它们会掩盖结合位点或稀释标记配体。我们已经为放射性配体和内源性配体结构相同的此类系统开发了一个数学模型。可以绘制将平衡时放射性配体结合作为样品体积函数的数据，从而以图形方式确定内源性配体和结合剂的浓度；然而，借助微型计算机通过非线性回归可以进行更精确的测定。该方法在一系列低于和高于饱和结合位点所需浓度的内源性生物素浓度存在下用于生物素结合蛋白的分析。
