4-Nitrophenol surface molecularly imprinted polymers based on multiwalled carbon nanotubes for the elimination of paraoxon pollution

Molecularly imprinted polymers were grafted on the surface of multiwalled carbon nanotubes (MWCNT) using the hydrolysis product of paraoxon 4-nitrophenol as template, 4-vinyl pyridine (4-VPy) as the functional monomer and divinylbenzen (DVB) as the crosslinker. The binding experiments of 4-nitrophenol indicated that the MWCNT based molecularly imprinted polymers (MWCNT-MIP) have much higher adsorption ability than the MWCNT based non-imprinted polymers (MWCNT-NIP). At the same time we found that the adsorption of 4-nitrophenol can help to increase the hydrolytic rate of paraoxon, which indicates that there is an obvious catalyzing effect on the hydrolysis of paraoxon for this kind of materials. Furthermore, the 4-nitrophenol left in the paraoxon hydrolysis medium is only 0.01056 mM for MWCNT-MIP in the catalytic experiment of paraoxon we made (the initial concentration of paraoxon is 0.5 mM and MWCNT-MIP is 4 mg), which indicates that this kind of MWCNT based imprinted polymers can not only catalyze the hydrolysis of paraoxon but also eliminate the poisonous organism product 4-nitrophenol. (C) 2012 Elsevier B.V. All rights reserved.