Enantoselective Resolution Based On Chitosan And β-Cyclodextrin Polymer Membranes

The article introduced briefly chirality,chiral separation methods and the significance of chiral separation,and focusing on chiral separation membranes.The major work is to prepare β-cyclodextrin-trimesoyl chloride polymer membrane and chitosan-glutaraldehyde polymer cross-linked membrane for study the separation of chirality membrane.Optimizing by orthogonal experiment for the chitosan-glutaraldehyde polymer cross-linked membrane prepared by cross-linking the chitosan-based membrane with glutaraldehyde,the dialysis separation e.e.value of D,L-phenylglycine on the membrane could reach 69.59 % under the condition of 0.2 mg/m L concentration of D,L-phenylglycine,p H 6.0 aqueous solution,20℃ temperature,60 h dialysis time,and the average resolution e.e.value was 68.56 %.The extraction separation e.e.value of D,L-phenylglycine on the membrane could reach 43.61 % with 0.08 mg/m L L-phenylglycine,p H 6.0 aqueous solution,25 min extraction time at 5℃,and the average extraction e.e.value was 42.60 %.The chitosan-glutaraldehyde polymer cross-linked membrane can also be used to separate D,L-p-hydroxyphenylglycine.When the concentration was 0.3 mg/m L D,L-p-hydroxyphenylglycine,p H value of the aqueous solution was 6.0,the temperature was 20℃,the dialysis time was 36 h,the dialysis separation e.e.value was 73.96 %,and the average separation e.e.value was 73.28 %.Under the 0.05mg/m L D,L-p-hydroxyphenylglycine,p H 6.0,the dialysis time was 15 min at 5℃,the extraction separation e.e.value for D,L-p-hydroxyphenylglycine was 45.08 %,and the average separation e.e.value was 44.12 %.A large-size β-cyclodextrin-trimesoyl chloride polymer membrane composite membrane was prepared on polyethersulfone base membrane by the interfacial polymerization reaction of β-cyclodextrin and trimesoyl chloride.After dialysis 36 h with 0.1 mg/m L D,L-mandelic acid（p H 5.0）at 15℃,the dialysis separation of over62.39 % e.e.value for D,L-mandelic acid was obtained,the average resolution e.e.value was 61.69 %,the further dialysis resolution e.e.value was 96.38 %.The chitosan and β-cyclodextrin polymer membranes possess good chiral recognition ability and has great application prospects for enantioselective resolution.