Novel immobilized metal ion affinity adsorbent based on cross-linked beta-cyclodextrin matrix for repeated adsorption of alpha-amylase

摘要

beta-Cyclodextrin (beta-CD) was chosen as the matrix material for the affinity binding of alpha-amylase in this work.beta-CD was cross-linked with epichlorohydrin to improve its rigidity.Iminodiacetic acid (IDA),as a ligand,was bond with the cross-linked beta-CD to increase the binding affinity for alpha-amylase.The affinity adsorbent thus prepared was further chelated with Cu~(2+) for the purpose of binding affinity and stability.The prepared affinity adsorbent was notated as beta-CD_(cl)-IDA-Cu~(2+).Excellent binding as well as de-binding was achieved within an extremely short period of time.Consequently,beta-CD_(cl)-IDA-Cu~(2+) successfully performed its ability on the affinity adsorption towards alpha-amylase.The adsorbent was also tested by its ability on repeated utilization.The result further confirmed that it could be repeatedly used and maintained the adsorption/desorption performance stably through many batches of operation.In addition,the bound alpha-amylase after many adsorption batches could be desorbed with a very high efficiency and hence rather high alpha-amylase activity could be collected.