Evaluation of the facilitated transport capabilities of nano- and micro-sized molecularly imprinted polymers (MIPs) in a bulk liquid membrane system

In this work, three types of molecularly imprinted polymers (MIP) containing atenolol selective sites were prepared by the methods of bulk polymerization, precipitation polymerization and suspension polymerization in silicon oil. Then, the MIP particles were used as the carrier elements in a bulk liquid membrane (BLM). Atenolol transport capabilities of different MIPs were compared with those of their relevant non imprinted polymers (NIP). It was shown that both nano- and micro-sized MIPs, obtained from suspension polymerization in silicon oil and precipitation polymerization, respectively, could transport atenolol more effective than the relevant NIPs. However, the nano-sized MIP was better than the micro-sized MIP for transportation of atenolol. Furthermore, the bulky MIP was not proper atenolol carrier in the BLM, since its transportation characteristic was similar to that of its relevant NIP. Moreover, the selectivity of the BLM containing different kinds of the MIPs obeyed the order of nano-MIP > micro-MIP > bulky MIP. The nano-MIP was adopted as the best atenolol carrier among the tested MIP-based carriers and then the effect of different factors on its transportation efficiency was evaluated. A kinetic model was proposed for the transportation of atenolol through the nano-MIP based BLM. It was found that the extraction of atenolol from the source to the membrane control the separation rate. (C) 2012 Elsevier B.V. All rights reserved.