MACROPOROUS CHITIN AFFINITY MEMBRANES FOR LYSOZYME SEPARATION

Macroporous chitin membranes with high, controlled porosity and good m echanical properties have been prepared using a technique developed in this laboratory based on silica particles as porogen. They were emplo yed for the affinity separation of lysozyme. Chitin membranes (1 mm th ickness) can be operated at high fluxes (greater than or equal to 1.1 mL/min/cm(2)) corresponding to pressure drops greater than or equal to 2 psi. Their adsorption capacity for lysozyme (similar to 50 mg/mL me mbrane) is by an order of magnitude higher than that of the chitin bea ds employed in column separation. In a binary mixture of lysozyme and ovalbumin, the membranes showed very high selectivity towards lysozyme . The effect of some important operation parameters, such as the flow rates during loading and elution were investigated. Lysozyme of very h igh purity (>98%) was obtained from a mixture of lysozyme and ovalbumi n, and from egg white. The results indicate that the macroporous chiti n membranes can be used for the separation, purification, and recovery of lysozyme at large scale. (C) 1997 John Wiley & Sons, Inc.