Bovine serum albumin functional MOF-919 novel membranes for effective separation of chiral enantiomers

Abstract

After modification of MOF-919 by bovine serum albumin (BSA) and further membrane formation, a novel metal-organic framework (MOF) chiral membrane based on protein functionalization was prepared. In the process, the stability of biomacromolecules under harsh conditions could be enormously raised on account of the combination MOF and BSA, while imparting chirality to the modified MOF. The influence of conditions such as reaction time, pH, initial concentration and salt concentration on the efficiency of MOF immobilized BSA were discussed. The outcomes indicated that the binding between MOF-919 and BSA was due to the synergistic interplay of pore diffusion and surface adsorption mechanisms. Meanwhile, after the immobilization, the composite material (MOF-919@BSA) was developed as a new kind of chiral splitter that combined with polyethersulfone to form the MMM. As well as the concentration of feed solution, thickness of membrane, proportion of biocomposite materials in membrane, the penetration time, cycle index and the micro environment of BSA on the separation of chiral enantiomers from the MMMs were investigated. The chiral membrane had excellent selectivity and high flux in the process of transporting chiral enantiomers. After that, the reliability of the mechanism for chiral separation was demonstrated through molecular docking simulations. At the same time, MOF@BSA-PES mixed matrix membrane manifested superior performance compared with the majority of state-of-the-art chiral membranes.