Chiral electrospun nanofibrous membranes for selective adsorption of chiral compounds

Chiral electrospun fibrous membranes with nanoscale fiber diameter were fabricated from synthetic polymers, poly(L-(-)-menthyl methacrylate) and poly(D-(+)-menthyl methacrylate), respectively, and employed as chiral filters for highly selective separation of chiral compounds. The structure and morphology of chiral nanofibrous membranes were controlled by adjusting the molecular weight of the polymer, the solution concentration, and the composition of solvents, verified with SEM measurements. To enhance the mechanical properties of a chiral nanofibrous membrane, polyacrylonitrile (PAN) was employed as second nanofibrous component serving as a skeleton, where a chiral nanofibrous composite membrane was fabricated through a two-nozzle electrospinning approach. Chiral compounds (S)-(-)-α- and (R)-(+)-α-phenethylamine were employed to challenge the separation efficiency of PAN/L-PMnMA and PAN/D-PMnMA nanofibrous composite membranes, in terms of the selective adsorption capability, while high selective factor was achieved for chiral isomers, implying that the chiral nanofibrous composite membrane could be potentially used for the chiral separation of natural products.