Direct purification of lysozyme from chicken egg white using weak acidic polyacrylonitrile nanofiber-based membranes

A highly efficient membrane process for direct purification of lysozyme from chicken egg white is reported. The ion‐exchange nanofibrous membrane (AEA‐COOH) comprises a polyethyleneterephthalate spunbond fabric as a supporting layer with upper and lower electrospun polyacrylonitrile nanofibrous layers treated with NaOH hydrolysis to transform CN bond into COOH functional group. SEM results demonstrate a porous structure with a fiber diameter ranged between 150 and 200 nm. Organic solvent residue analysis proves no significant dimethylacetamide release from electrospun polyacrylonitrile nanofibers. The lysozyme was directly purified from the chicken egg white using Millipore stirred cell reactor equipped with AEA‐COOH membranes. Despite a protein recovery of only 22.3%, the purified lysozyme had an activity recovery as high as 80.5% with a 73.6‐fold purification. SDS‐PAGE confirms the purified lysozyme product. This study thereby verified that lysozyme protein can be isolated and purified directly from chicken egg whites using AEA‐COOH membranes. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012