Preparation of core-shell molecularly imprinted polymer via the combination of reversible addition-fragmentation chain transfer polymerization and click reaction

Analysis and Measure Center, Jilin Normal University, Siping 136000, China.
Analytica chimica acta (Impact Factor: 4.51). 11/2010; 680(1-2):65-71. DOI: 10.1016/j.aca.2010.09.017
Source: PubMed


In this paper, we demonstrated an efficient and robust route to the preparation of well-defined molecularly imprinted polymer based on reversible addition-fragmentation chain transfer (RAFT) polymerization and click chemistry. The alkyne terminated RAFT chain transfer agent was first synthesized, and then click reaction was used to graft RAFT agent onto the surface of silica particles which was modified by azide. Finally, imprinted thin film was prepared in the presence of 2,4-dichlorophenol as the template. The imprinted beads were demonstrated with a homogeneous polymer films (thickness of about 2.27 nm), and exhibited thermal stability under 255°C. The as-synthesized product showed obvious molecular imprinting effects towards the template, fast template rebinding kinetics and an appreciable selectivity over structurally related compounds.

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    • "The presence of a reactive surface in the 'grafting from' approach allows a greater control of the polymerization process, above all in terms of length and density of surface polymer chains and for these reasons its use has been recently increased. On this basis, in order to efficiently develop thin controlled polymeric layers, in recent years, various surface molecular imprinting techniques based on 'iniferter' [Ruckert et al., 2002; Perez-Moral and Mayes, 2007; Barahona et al., 2010], 'reversible addition-fragmentation chain transfer' [Titirici and Sellergren, 2006; Pan et al., 2009; Chang et al., 2010] and 'atom transfer radical polymerization' [Wei et al., 2005; Zu et al., 2009; Sasaki et al., 2010] have been developed. Besides these methods to prepare controlled imprinted thin layers, a non-conventional approach to surface molecular imprinting has been reported [Matsui et al., 2002; Li et al., 2005]. "
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