Removal of endotoxin from human-like collagen solution by anion-exchange chromatography

Response surface analysis methodology(RSM) was used for optimizing the removal process of endotoxin from human-like collagen(HLC) solution based on anion-exchange chromatography.The effects of three crucial factors(HLC mass concentration,pH value and NaCl concentration) on endotoxin removal efficiency(ERE) and HLC recovery rate were investigated by using one-factor-at-a-time design.The response surface central composition design,in which the interactions between the variables were considered,was applied to optimize these factors.A quadratic polynomial regression model was developed.The optimal endotoxin removal efficiency conditions are as follows: the mass concentration of HLC is 0.95 mg/mL,pH=7.6 and NaCl concentration is 50 mmol/L.Under such conditions,the endotoxin removal efficiency and HLC recovery rate are 97.92% and 98.01% respectively.