Preparation and Characterization of Carboxymethyl Chitosan Modified Magnetic Nanoparticles for Bovine Serum Albumin Adsorption

Carboxymethyl chitosan (CMC) were prepared from the carboxymethylation reaction of chitosan under mild conditions, and magnetic carboxymethyl chitosan nanoparticles (MNPs-CMC) were developed by binding CMC on the surface of magnetic Fe3O4 nanoparticles (MNPs) via EDC/NHS activation. The characterization results indicated that MNPs were successfully modified by CMC and the modified nanoparticles had a good magnetic property. By investigating the adsorption of BSA, it was found that the maximum BSA immobilization capacity was up to 159.51 mg·g−1. The adsorption characteristics of BSA can fit the pseudo-second-order model and Langmuir equation well. Furthermore, a high desorption efficiency of 81.47% was achieved under an alkaline condition (pH 9.6).