Graphene oxide based molecularly imprinted polymers with double recognition abilities : The combination of covalent boronic acid and traditional non-covalent monomers

Abstract

In this work, graphene oxide (GO) based molecularly imprinted polymers with double recognition abilities (DR-MIPs) were prepared and considered as adsorbent for the specific recognition and capture of luteolin (LTL). To exhibit the tightest binding hosts for LTL, the double recognition abilities were achieved by adopting 4-vinylphenyl boronic acid (BA) and methacrylic acid (MAA) to be the covalent and non covalent imprinted monomers, respectively. Then, their functional groups and shape of imprinted sites endowed DR-MIPs with a specific affinity for cis-diol-containing structure, hydroxyl and carbonyl groups of LTL. The results of batch mode experiments indicated kinetic equilibrium time and binding capacity of DR-MIPs were 30 min and 56.27 mg g(-1) at 298 K, respectively. The Langmuir isotherm and pseudo second-order kinetic models were the main adsorption mechanisms for DR-MIPs, and the fast adsorption and large binding amount were resulted from the two-dimensional (2D) structure of GO and enough imprinted sites with double recognition abilities. DR-MIPs also showed excellent recognition ability, and the estimated relative selectivity coefficients (k') for structural analog quercetin (QRT), hydroquinone (HDQ) and p-nitrophenol (P-NP) were 13.73, 18.62 and 19.95, respectively. In addition, DR-MIPs possessed outstanding reusability and enhanced purification property for 85% raw LTL. The purified LTL products achieved approximately 93.47%, and they exhibited the obvious antibacterial performance