A novel approach to chiral separation: thermo-sensitive hydrogel membranes

Fourier transform infrared spectroscopy (FTIR) techniques revealed a transition in the secondary structure of BSA from α-helix to β-sheet as the temperature increased. This transition, facilitated by hydrogen bonding between BSA and PNIPAm, enabled selective recognition of D-Phe, demonstrating a distinct shift in chiral recognition properties. Importantly, with D-Phe adsorbed onto β-sheet structures of BSA, hydrogen-bond interactions between BSA and the PDTAN membrane were significantly reduced, thereby minimizing membrane fouling and achieving the durability of membrane-based chiral separation.