Catechin-Molecularly Imprinted Cryogel for Determination of Catechin in Red Wines by HPLC-DAD-Fluorescence Detector

Abstract

A new molecularly imprinted polymer (MIP) was prepared by using catechin (C) as the template molecule. The polymer was characterized by swelling tests, scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), and Fourier transform infrared (FTIR) spectroscopy. The MIP with high recovery was selected as a solid-phase extraction (SPE) sorbent in this work. The standard solutions were directly applied onto the SPE cartridges following loading, washing, and elution procedures. A solution of the collected fractions was analyzed by high-performance liquid chromatography-diode-array detection (DAD) and fluorescence detector. The optimization of the method and validation was achieved on a C18 column (5 mu m, 250 x 4.6 mm) with methanol-water (35:65, v/v) mixture adjusted pH 2.5 as the mobile phase at a flow rate of 1 mL min(-1) at room temperature. The selectivity coefficient (k) of imprinted p(HEMA-MAH) cryogel was 5.1-fold that of non-imprinted cryogel. It showed good selectivity and affinity for C molecule. A comparison was made between the results obtained with the MIP cartridges and a traditional C18 reversed-phase cartridge. It was observed that 2.3 times higher recovery of C can be obtained on catechin-MIP cryogel. The results of the presented work showed that the prepared MIP can be used as SPE sorbent for extracting of C from red wines.