Larsen C G, Larsen F G, Brodersen R
J Pharm Sci. 1986 Jul;75(7):669-71. doi: 10.1002/jps.2600750710.
It has been found that binding of low molecular weight ligands to human serum albumin is generally nonsaturating. Equations commonly used for describing the binding equilibria, i.e., the Scatchard and Klotz (Adair) equations, are saturation functions. We have accordingly tried to establish an equation which would fit the observed data, i.e., not reach a saturation plateau. An empirical equation, in which the bound ligand is expressed as a function of the free ligand [R(C) = b1 in (b2C + 1)], is shown to give reasonably good fits to observed binding equilibrium data for the binding of several organic ligands to human serum albumin, when the two parameters, b1 and b2, are given suitable values. The curve of bound versus free ligand, as plotted from this equation, has the same slope and curvature as that obtained from the Klotz stepwise binding equation at C = 0, if b1 = K1/[2(K1 - 2K2)] and b2 = 2(K1 - 2K2), where K1 and K2 are the first and second stoichiometric binding constants.
已发现低分子量配体与人血清白蛋白的结合通常不饱和。常用于描述结合平衡的方程，即Scatchard方程和Klotz（Adair）方程，都是饱和函数。因此，我们试图建立一个能拟合观测数据的方程，即不会达到饱和平台。一个经验方程[R(C) = b1 ln(b2C + 1)]，其中结合的配体表示为游离配体的函数，当给出两个参数b1和b2的合适值时，对于几种有机配体与人血清白蛋白的结合，该方程能较好地拟合观测到的结合平衡数据。如果b1 = K1/[2(K1 - 2K2)]且b2 = 2(K1 - 2K2)，其中K1和K2是第一和第二化学计量结合常数，由该方程绘制的结合配体与游离配体的曲线在C = 0时与从Klotz逐步结合方程得到的曲线具有相同的斜率和曲率。
