β-环糊精与双金属石墨烯复合材料对酪氨酸对映体的电化学选择性作用

Stereoselective interaction of tyrosine enantiomers based on β-Cyclodextrin and bimetallic reduced graphene oxide nanohybrids modified electrode

选择β-环糊精(β-CD)作为手性选择剂,将其滴涂到经金铂纳米合金与还原氧化石墨烯复合材料(Au-PtNPs/rGO)修饰的玻碳电极表面,得到β-CD/Au-PtNPs/rGO修饰电极;采用差分脉冲伏安法(DPV)研究该修饰电极与酪氨酸对映体(D-或L-Tyr)的相互作用。实验结果表明,修饰电极可分别与D-或L-Tyr作用,并呈现不同的电流响应,其中与L-Tyr作用后的峰电流值明显高于D-Tyr,二者电流差值(ΔI_p=I_(pL-Tyr)-I_(pD-Tyr))为9.5μA。在0.1 mmol/L至5.0 mmol/L范围内,酪氨酸对映体的峰电流值与其浓度呈现线性关系。此方法为电化学手性识别传感器的发展提供了一定的理论基础,具有潜在的应用价值。

A simple chiral sensing platform has been fabricated by. immobilizing β-cyclodextrin （β-CD） on the sur- face of Au-Pt alloy nanoparticles （Au-PtNPs） and reduced graphene oxide （rGO） modified glassy carbon electrodes （GCE）. It has been used for stereoselective interaction with tyrosine enantiomers （D-/L-Tyr） via differential pulse vohammetry （DPV）, and β-CD was applied as a chiral selector to interact with D-Tyr and L-Tyr. The results showed larger differences in the peak currents of L-Tyr than that of D-Tyr, and the difference of peak currents （Alp =/pL-Tyr -- IpD-Tyr） was 9.5 μA. The oxidation peak currents of tyrosine enantiomers were linearly related to their concentrations in the range of 1.0×l0-3 mol/L - 5.0×10-3 mol/L. This method provided a theoretical and practical significance to comprehend the stereoselective interaction between hybrids and analytes.