Effect of Sericin Additive on Cellulose Acetate Membrane Morphology and Protein Rejection

Abstract

Cellulose acetate (CA) membranes are synthesized for filtration purpose. The hydrophilic sericin macromolecule is blended with CA to analyze the enhancement of protein rejection. Increase in hydrophilicity, water permeation and protein rejection was studied by using contact angle, pure water flux (PWF) and Bovine serum albumin (BSA) permeation respectively. Surface modification was examined using SEM and AFM. The results show the homogenous blending of sericin in CA matrix and effective fabrication of membranes. In order to gauge the efficiency of casted membranes in protein filtration and separation, water flux and protein rejection were studied. The concentration of sericine protein was altered in CA polymeric solution that imparts variable properties to fabricated membrane samples. Increment in wt% of sericine up to 7.5 in polymer dope solution, enhances BSA rejection to the limit of 96%. The amino linkages between sericine and the BSA of feed resulted in the holding of protein by sericine, which leads to low permeation of BSA via CA-Sericine membrane M4.