Ahrer Karin, Buchacher Andrea, Iberer Günter, Jungbauer Alois
Department of Biotechnology, University of Natural Resources and Applied Life Sciences, Muthgasse 18, A-1190 Vienna, Austria.
J Biochem Biophys Methods. 2006 Mar 31;66(1-3):73-86. doi: 10.1016/j.jbbm.2005.12.003. Epub 2006 Jan 19.
The final process step of polyclonal human immunoglobulin G is formulation with agents such as sugars, polyols, amino acid and salts. Often the most stable formulations were empirically identified. Physicochemical methods, such as differential scanning calorimetry and dynamic light scattering, provide a deeper insight on the biophysical properties of such a protein solution. The combination of these methods proved to be sensitive enough to detect fine differences in the properties relevant for the development of stable protein solutions. The influence of additives, such as maltose and glycine in combination with water or low concentrations of salts, on human immunoglobulin preparations was analysed. Differential scanning calorimetry illustrated that 0.2 M glycine had better stabilising effects compared to 10% maltose. Dynamic light scattering and differential scanning calorimetry revealed that solutions preventing aggregation were not optimal in terms of thermodynamic stability. Aggregation was minimised with increasing ionic strength, shown by dynamic light scattering, whereas thermodynamic stability for heat sensitive parts of human immunoglobulin G, analysed with differential scanning calorimetry, was decreased.
多克隆人免疫球蛋白G的最后一道工艺步骤是与糖类、多元醇、氨基酸和盐类等制剂进行配方调配。通常，最稳定的配方是通过经验确定的。物理化学方法，如差示扫描量热法和动态光散射法，能更深入地了解此类蛋白质溶液的生物物理性质。事实证明，这些方法的组合足够灵敏，能够检测出与稳定蛋白质溶液开发相关的性质的细微差异。分析了添加剂（如麦芽糖和甘氨酸与水或低浓度盐的组合）对人免疫球蛋白制剂的影响。差示扫描量热法表明，与10%的麦芽糖相比，0.2M的甘氨酸具有更好的稳定效果。动态光散射和差示扫描量热法显示，防止聚集的溶液在热力学稳定性方面并非最佳。动态光散射表明，随着离子强度的增加，聚集最小化，而用差示扫描量热法分析的人免疫球蛋白G热敏感部分的热力学稳定性则降低。
