ProteinsPlatform constructed from biofuctionalized-magnetized nano-chitosan for efficient separation of multi-tagged fusion proteins

Chitosan (CS) was deposited onto the surface of Fe 3 O 4 nanoparticles by anionic cross-linking to obtain Fe 3 O 4 @CS nanocomposite with improved biocompatibility ascribed to CS. The optimized reaction condition for preparing Fe 3 O 4 @CS was established. Furthermore, polyacrylic acid (PAA) was grafted onto the surface of Fe 3 O 4 @CS to obtain magnetically responsive Fe 3 O 4 @CS/PAA nanocomposite; and dextrin was grafted onto the surface of Fe 3 O 4 @CS/PAA by hydrogen bonding to obtain Fe 3 O 4 @CS/dextrin nanoadsorbent with desired magnetic response for the rapid purification of the maltose binding protein-tagged (MBP-tagged) fusion proteins from Escherichia coli lysate. The as-obtained Fe 3 O 4 @CS/PAA nanocomposite was loaded with relevant antibodies to construct the platform for the purification of MBP-tagged, glutathione S-transferase-tagged, and histidine-tagged fusion proteins. Findings demonstrate that multi-tagged proteins platform exhibits rapid recognition and high binding abilities as well as desired specification, universality, and recycling ability to the tested tagged fusion proteins, because they can strongly load different protein ligands.