Formulation Development, CMC Development, Eli Lilly and Company, 59-61 ImClone Drive, Branchburg, NJ 08876, USA.
Formulation Development, CMC Development, Eli Lilly and Company, 59-61 ImClone Drive, Branchburg, NJ 08876, USA.
Int J Biol Macromol. 2015;77:260-5. doi: 10.1016/j.ijbiomac.2015.03.027. Epub 2015 Mar 25.
Pace et al. (1995) [1] recommended an equation used to predict extinction coefficient of a protein. However, no antibody data was included in the development of this equation. The main objective of this study was to therefore investigate how the predicted value of the extinction coefficient is comparable to the experimentally determined extinction coefficient of antibodies measured by the Edelhoch method. We have measured the extinction coefficients (ɛ) of 13 IgG1 monoclonal antibodies (mAbs) in phosphate buffer at pH 7.2. The maximum variability in the experimentally measured extinction coefficient of a given mAb molecule was found to be about 2%. Experimentally determined extinction coefficients of all mAbs were found to be lower than the predicted value, with the maximum difference found to being 4.7%. The highest and lowest values of experimental extinction coefficient among the thirteen IgG1 monoclonal antibodies obtained were 230525.9M(-1)cm(-1) (i.e. 1.55(mg/ml)(-1)cm(-1)) and 191,411.6M(-1)cm(-1) (i.e. 1.29(mg/ml)(-1)cm(-1)). A difference of <3% (with respect to mean value) was observed between the experimental and predicted values of the extinction coefficient. A comprehensive analysis and interpretation of the comparison of the predicted and experimentally determined extinction coefficient by the Edelhoch method is discussed in terms of structural characterization and accessible surface area (ASA).
佩斯等人（1995 年）[1]推荐了一个用于预测蛋白质消光系数的方程。然而，该方程的开发中并未包含抗体数据。因此，本研究的主要目的是研究预测的消光系数值与通过 Edelhoch 方法测量的抗体的实验确定的消光系数值如何进行比较。我们已经测量了 13 种 IgG1 单克隆抗体（mAb）在 pH7.2 的磷酸盐缓冲液中的消光系数（ɛ）。发现给定 mAb 分子的实验测量消光系数的最大可变性约为 2%。所有 mAb 的实验确定消光系数均低于预测值，最大差异发现为 4.7%。在 13 种 IgG1 单克隆抗体中，实验获得的最高和最低实验消光系数值分别为 230525.9M-1cm-1（即 1.55(mg/ml)-1cm-1）和 191,411.6M-1cm-1（即 1.29(mg/ml)-1cm-1）。实验和预测消光系数值之间观察到的差异<3%（相对于平均值）。从结构特征和可及表面积（ASA）方面讨论了 Edelhoch 方法预测和实验确定消光系数的比较的全面分析和解释。
