Electrochemical Chiral Recognizing Tryptophan Enantiomers Based on Chiral Metal-Organic Framework D-MOF

In this work, an electrochemical chiral sensor of a nanowire-like chiral metal-organic framework/multiwalled carbon nanotube-chitosan/glassy carbon electrode(D-MOF/MWCNTs-CS/GCE) was proposed for the enantiorecognition of L/D-tryptophan(L/D-Trp). The asymmetrical spatial structure of D-MOF provides the feasibility for the enantiorecognition of Trp enantiomers. Moreover, differential pulse voltammetry(DPV) was carried out to be the detection method and the DPV peak potential difference(ΔE _p) between L-Trp and D-Trp was referred as the index of the enantiorecognition performance. Several parameters, such as mass ratios and drop-coated volume of MWCNTs-CS, drop-coated volume and concentration of D-MOF, pH and detection temperature of D-MOF/MWCNTs-CS/GCE were optimized for the largest ΔE _p value. And the molecular dynamics(MD) simulation was used to elucidate the enantiorecognition mechanism. Furthermore, the proportions of D-Trp(D-Trp%) in Trp mixtures were detected in a good linear relationship with the DPV peak potentials(E _p), and the proposed electrochemical chiral sensor exhibited good reproducibility, stability and enantiorecognition ability. Additionally, the proposed electrochemical chiral sensor(D-MOF/MWCNTs-CS/GCE) has a good application prospect in the fields of biomedicine, clinical diagnosis, chemical production, pharmaceuticals safety and so on. [Figure not available: see fulltext.]