Chiral Recognition of Tryptophan Enantiomers Based on β-Cyclodextrin-platinum Nanoparticles/Graphene Nanohybrids Modified Electrode

The nanohybrids which based on β-cyclodextrin, platinum nanoparticles and graphene (β-CD-PtNPs/GNs) were successfully synthesized and characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), fourier transform infrared spectroscopy (FT-IR) and electrochemical impedance spectroscopy (EIS). Then they were used to construct a simple and reliable chiral sensing platform to interact with tryptophan (Trp) enantiomers. Differential pulse voltammetry (DPV) was used to investigate the stereo selectivity of β-CD-PtNPs/GNs to Trp enantiomers. After interaction, the obvious difference of peak currents of L -Trp and D -Trp was obtained, indicating this strategy could be employed to chiral recognition of Trp enantiomers. Under the optimum conditions, the chiral sensor exhibited a good linear response to Trp enantiomers in a linear range of 5.0×10 −5 to 5.0×10 −3 M with a low limit of detection of 1.7×10 −5 M (S/N=3). This approach provided a new available platform to recognize and determine Trp enantiomers.