Wallace Vincent P, Ferachou Denis, Ke Peng, Day Katie, Uddin Shahid, Casas-Finet Jose, Van Der Walle Christopher F, Falconer Robert J, Zeitler J Axel
School of Physics, University of Western Australia, Crawley, Western Australia 6009, Australia.
Department of Chemical Engineering & Biotechnology, University of Cambridge, Cambridge CB2 3RA, UK.
J Pharm Sci. 2015 Dec;104(12):4025-4033. doi: 10.1002/jps.24630. Epub 2015 Sep 7.
Terahertz time-domain spectroscopy (THz-TDS) has been shown to detect overlapping extended hydration layers around proteins. Here, we used THz-TDS to detect modulation of the extended hydration layer around monoclonal antibodies (mAbs) by the introduction of commonly used excipients. Proline and sucrose altered the hydration layer around a mAb (mAb1), which was observed as a negative shift in the plateau in absorbance above 100 mg/mL mAb1 (70,000 water molecules per mAb); arginine had no effect. At lower concentrations of 10 mg/mL mAb1 (700,000 water molecules per mAb) proline and arginine modulated the hydration layer, which was observed as a negative shift in the relative absorbance, whereas sucrose had no effect. The changes in the extended hydration layer were not translated to shifts in the thermal stability or protein:protein interaction parameter. The hydration layer of a second mAb (mAb2) was further shown to be modulated by more complex formulations composed of two or more excipients; although the differences in terahertz absorbance were not predictive of viscosity or long-term stability. THz-TDS promises to be a useful tool for understanding a protein's interaction with excipients in solution and the challenge will be to determine how to apply this knowledge to protein formulation.
太赫兹时域光谱（THz-TDS）已被证明可检测蛋白质周围重叠的扩展水合层。在此，我们使用THz-TDS来检测通过引入常用辅料对单克隆抗体（mAb）周围扩展水合层的调制。脯氨酸和蔗糖改变了一种单克隆抗体（mAb1）周围的水合层，在mAb1浓度高于约100 mg/mL（每mAb约70,000个水分子）时，观察到吸光度平台出现负移；精氨酸没有影响。在较低浓度的约10 mg/mL mAb1（每mAb约700,000个水分子）时，脯氨酸和精氨酸调制了水合层，表现为相对吸光度的负移，而蔗糖没有影响。扩展水合层的变化并未转化为热稳定性或蛋白质：蛋白质相互作用参数的变化。另一种单克隆抗体（mAb2）的水合层进一步被证明会受到由两种或更多种辅料组成的更复杂配方的调制；尽管太赫兹吸光度的差异并不能预测粘度或长期稳定性。太赫兹时域光谱有望成为理解蛋白质在溶液中与辅料相互作用的有用工具，而挑战将是确定如何将这些知识应用于蛋白质配方。
