The Aviv fluorescence detection system (Aviv-FDS) has allowed the performance of sedimentation velocity experiments on therapeutic antibodies in highly concentrated environments like formulation buffers and serum. Methods were implemented in the software package SEDANAL for the analysis of nonideal, weakly associating AUC data acquired on therapeutic antibodies and proteins (Wright et al. Eur Biophys J 47:709–722, 2018, Anal Biochem 550:72–83, 2018). This involved fitting both hydrodynamic, k_s, and thermodynamic, BM₁, nonideality where concentration dependence is expressed as s = s^o/(1 + k_sc) and D = D^o(1 + 2BM₁c)/(1 + k_sc) and s^o and D^o are values extrapolated to c = 0 (mg/ml). To gain insight into the consequences of these phenomenological parameters, we performed simulations with SEDANAL of a monoclonal antibody as a function of k_s (0–100 ml/g) and BM₁ (0–100 ml/g). This provides a visual understanding of the separate and joint impact of k_s and BM₁ on the shape of high-concentration sedimentation velocity boundaries and the challenge of their unique determination by finite element methods. In addition, mAbs undergo weak self- and hetero-association (Yang et al. Prot Sci 27:1334–1348, 2018) and thus we have simulated examples of nonideal weak association over a wide range of concentrations (1–120 mg/ml). Here we demonstrate these data are best analyzed by direct boundary global fitting to models that account for k_s, BM₁ and weak association. Because a typical clinical dose of mAb is 50–200 mg/ml, these results have relevance for biophysical understanding of concentrated therapeutic proteins.

Aviv荧光检测系统（Aviv-FDS）允许在制剂缓冲液和血清等高度浓缩的环境中对治疗性抗体进行沉降速度实验。在SEDANAL软件包中实施了用于分析从治疗性抗体和蛋白质获得的非理想的，弱关联的AUC数据的方法（Wright等人，Eur Biophys J 47：709-722，2018，Anal Biochem 550：72-83，2018） 。这涉及拟合流体力学k _s和热力学BM _1的非理想性，其中浓度依赖性表示为s  =  s ^o /（1 +  k _s c）和D  =  D ^o（1 + 2BM ₁ c）/（1 +  k _s c）和s ^o和D ^o是外推到c  = 0（mg / ml）的值。为了深入了解这些现象学参数的后果，我们使用SEDANAL对k _s（0-100 ml / g）和BM ₁（0-100 ml / g）的函数进行了SEDANAL模拟。这可以直观地了解k _s和BM _1的相互影响。高浓度沉降速度边界的形状及其对有限元方法唯一确定的挑战。此外，单克隆抗体会经历弱的自缔合和异缔合（Yang等人，Prot Sci 27：1334-1348，2018），因此我们模拟了在宽范围的浓度（1-120 mg / ml）下非理想弱缔合的实例）。在这里，我们证明了这些数据最好通过直接边界全局拟合到考虑k _s，BM ₁和弱关联的模型来进行分析。因为mAb的典型临床剂量为50-200 mg / ml，所以这些结果与浓缩治疗蛋白的生物物理意义有关。