The Construction And Application Of Chiral Interfaces

Chirality is the essential attribute of organism and even nature, and the chiral selectivity is an inexorable law in the life process. The different configurations of enantiomer have similar physical properties, but differ vastly in chemical properties and pharmacological activities. Therefore, the research of chiral recognition has important theoretical and practical significance in medicinal chemistry, life sciences, food technology and materials science field, and the research on chiral recognition in analytical chemistry is developing an accurate, rapid, sensitive and low cost chiral analysis method. Based on the above considerations, this paper builds three different chiral interfaces, and achieves the electrochemical chiral recognition of electroactive molecules. The main contents are as follows:1. N-isobutyryl-cysteine enantiomers (L- or D-NIBC) can bond chemically with Au to form well-organized self-assembly membranes (SAMs) via hydrosulfide group (-SH), thus an easy and sensitive electrochemical method has been developed to achieve chiral recognition of NIBC enantiomers via the electrochemincal response of L-Methotrexate (L-Mtx) on different configuration of NIBC modified Au electrodes. The distinctive difference of current suggesting the obvious selective interaction was existed between NIBC enantiomers and L-Mtx. And the interaction activity has been greatly affected by the concentration and the pH value. Results showed that L-NIBC modified Au electrodes having a stronger interact with L-Mtx. This work simple, fast and effective, and provides a new model for the other electrochemical recognition of chiral molecules and chiral drugs.2. The chiral composite films (MWCNTs-β-CD/PANI/NiHCF), which prepared by multiwalled carbon nanotubes (MWCNTs),β-cyclodextrin (β-CD), polyaniline (PANI), and nickel hexacyanoferrate (NiHCF), were used to interact with tyrosine enanotimers via differential pulse voltammetry (DPV) technique, and a distinctive difference in current suggestive of the proposed chiral sensor could distinguish L- and D-Tyr. Scanning electron microscopy (SEM) was used to observe the surface morphology and structure of chiral composite films, cyclic voltammetry (CV) was used to study the influence of the electrode construction process, the polymerization conditions, the pH value of bottom and the incubation time. In addition, the recognition was considerably affected by polymerization laps. It was a simple, low cost, and high sensitivity method with good selectivity for distinguishing Tyr enantiomers. The nano-metal composite material has excellent electrochemical properties, and it is conducive to the development of new chiral electrochemical sensor interface.3. Chloroplatinic acid and L-valine (L-val) were mixed by a certain percentage, and then the L-val platinum-doped polymeric films were synthesized on the glassy carbon electrode (GCE) surface with "one-step" strategy, building a simple chiral sensing nanoplatform, and used to electrochemical identify of propranolol enantiomers (R-or S-PRO) successfully. Differential pulse voltammetry (DPV) technique was used to study the effect between this chiral interface and propranolol enantiomers, which propranolol was treated as redox probes. In addition, the recognition was considerably affected by the interface, the concentration of target analytes, pH value and platinum content. The results showed that-this chiral interface has a stronger interact with R-PRO, and it was efficacious to achieve the selective recognition of propranolol enantiomers.