Paper Title
Rapid Purification of Lysozyme From Chicken Egg White by Ion Exchange Nanofibrous Membrane Chromatography

Polyacrylonitrile (PAN) nanofibrous membrane was prepared by electrospinning technique. The PAN membrane used in this work comprises a polyethylene terephthalate (PET) spunbond fabric as a supporting layer with upper and lower PAN nanofibrous membrane. After 3M NaOH and diluted HCl treatments, the weak cationic exchange membrane (i.e., AEA-COOH) was obtained. The AEA-COOH membrane was then functionalized with ethylenediamine (EDA) and bromoacetic acid (BrA), sequentially. This modified ion exchange membrane (namely AEA-BrA) has more acidic groups as compared to the AEA-COOH membrane. In this study, lysozyme obtained from chicken egg white (CEW) was chosen as a model enzyme. The adsorption characteristics of the AEA-BrA membranewere assessed by measurements of the breakthrough curves in membrane chromatography. The influences of adsorption pH, CEW concentration, and liquid flow rate on adsorption performance of the membrane were investigated in an AKTA prime chromatographic system (GE Healthcare). On the basis of the results, the optimal conditions for the capture of lysozyme were carried out in 10% (v/v) CEW at pH 9 and flow rate of 0.1 mL/min for the ion exchange membrane process. Moreover, the two-step elution scheme (0.6 M and 1.0 M NaCl, pH 9) was chosen for eluting the adsorbed lysozyme. The lysozyme fraction eluted by second step 1.0 M NaClwas recovered with purification factor of 402 and yield of 91% in AEA-BrA ion exchange membrane chromatography. Index Terms - Chicken egg white (CEW), electrospinning technique, Polyacrylonitrile (PAN) nanofibrous membrane