Influence of Salts on the Adsorption of Lysozyme on a Mixed-Mode Resin

Mixed-mode chromatography (MMC), which combines features of ion exchange (IEC) and hydrophobic interaction (HIC), is an interesting method for protein separation purification. The design MMC processes challenging as adsorption equilibria are influenced by many parameters, including ionic strength the presence different salts in solution. Systematic studies on influence those parameters rare. Therefore, present work, four salts, namely, sodium chloride, sulfate, ammonium lysozyme mixed-mode resin Toyopearl MX-Trp-650M at pH 7.0 25°C was studied systematically equilibrium experiments strengths between 0 mM 3000 mM. For all a noticeable observed over entire range strengths. An exponential decay loading with increasing found until approx. 1000 higher strengths, to be practically independent strength. At constant strength, highest loadings were lowest chloride. A mathematical model developed that correctly describes well salts. first enables prediction isotherms proteins resins wide technically conditions, accounting practical relevance.