Porous boronate imprinted microsphere prepared based on new RAFT functioned cellulose nanocrystalline with multiple H-bonding at the emulsion droplet interface for highly specific separation of Naringin

Abstract

For porous molecular imprinted polymers (MIPs), introduction of special functional groups and integration porous structure support will endow the MIPs with tunable surface properties and specific affinity performance. Herein, by combination of RAFT molecular imprinting, Pickering emulsion, and boronate affinity methods, a new kind of porous imprinted microspheres (BA-HPMIPs) using the low pKa value of APBA (1-allylpyridinium-3-boronic acid, pKa = 7.4) as functional monomer was prepared for specific molecular recognition and separation of NRG. Meanwhile, the novel RAFT functioned surfactants with dual amide multiple H-bonds were designed as stabilized particles was used to promote sustainability, which further confer them multifunctionality and/or by polymerizing the Pickering emulsion itself. Equilibrium adsorption was reached rapidly within 360 min, and the maximum equilibrium binding capacities of BA-HPMIPs were found to be 118.32 µmol g−1 for NRG. Furthermore, they had a stronger selectivity towards NRG than other competitive target (i.e rutin, catechol, ARS, o-nitrophenol). Moreover, BA-HPMIPs have shown outstanding reusability of 8.63 % loss in enrichment performance after five times repeatedly. As a proof of this concept, a commercially avaliable NRG with purity could be effectively extracted and concentrated to 96.75 % purity. These results demonstrated that, a new kind of porous imprinted microsphere with abundant porous structure and boronic acid recognizing sites has great potential for separation and purification of industrial samples under neutral conditions.