Molecularly imprinted particle embedded composite cryogel for selective tetracycline adsorption

Abstract

The aim of this study was to prepare a composite cryogel for selective tetracycline(TC) adsorption. The composite cryogel was prepared by embedding TC-imprinted poly (hydroxyethyl methacrylate-N-methacryloyl-Lglutamic acid methyl ester [poly(HEMA-MAGA)] particles into poly(hydroxyethyl methacrylate) [PHEMA] cryogel. Molecular imprinting was used to prepare poly(HEMA-MAGA) particles with selective recognition sites for TC molecule. The TC-imprinted poly(HEMA-MAGA) particles were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and zeta size analysis. The morphology of the composite cryogel was investigated by using scanning electron microscope (SEM). Swelling degree, specific surface area, pore volume and pore diameter of TC-imprinted composite cryogel were also determined. TC solutions in different concentrations (5-85 mg/L, pH 5.0) were used to determine TC adsorption capacity of the TC-imprinted composite cryogel for three different temperatures (4 degrees C, 13 degrees C and 25 degrees C). TC adsorption capacity of the TC-imprinted composite cryogel was determined as 680 mg TC/g at 25 degrees C (pH 5.0). TC adsorption data were fitted with Freundlich adsorption isotherm model for three different temperatures (4 degrees C, 13 degrees C and 25 degrees C). Both pseudo-second-order and intraparticle diffusion kinetic models explained the adsorption process. The prepared TC-imprinted composite cryogel can be repeatedly used for TC adsorption. The composite cryogel has high adsorption capacity and selectivity, demonstrating the applicability for selective TC adsorption.