lectrochemical recognition and quanti fi cation of amine enantiomers based on a guest-free homochiral MOF †

Many important molecules in the modern pharmaceutical and agrochemical industries, are chiral—that is, they are not superimposable on their mirror image, the pair of asymmetric molecules are known as enantiomers. The recognition and quantication of enantiomers is a major challenge particularly owing to their identical physical and chemical properties in an achiral environment. In many cases, one of the enantiomers exhibits the desired responses while the other is inactive or even toxic. The present technology depends largely upon nuclear magnetic resonance (NMR), gas chromatography (GC) and high performance liquid chromatography (HPLC) based on homochiral stationary phases (CSPs), which is of particular importance for laboratories and industries in the discovery and development of enantiomeric substances and quality control of corresponding products. However, these methods require high concentrations of analytes, sophisticated operation, relatively expensive instrumentation, and GC and HPLC are also typically time-consuming. Molecularly imprinted polymers (MIPs) have more than 80 years of history, considerable advances have been made on the fundamental study. Although the approach behaves special desired selectivity because the MIPs create three-dimensional cross-linked polymers with tailor-madememory of the shape, size and functional groups for a template or target molecule, this sometimes also suffers from some problems, such as incomplete template removal, poor mass transfer, low binding capacity and slow binding kinetics, which restricts its applications in various aspects. In contrast, the electrochemical sensors can provide highly selective, low cost, fast speed, real time and on-line