Molecularly imprinted polymers covalent

Molecularly imprinted polymers (MIPs) can be prepared according to a number of approaches that are different in the way the template is linked to the functional monomer and subsequently to the polymeric binding sites (Fig. 6-1). Thus, the template can be linked and subsequently recognized by virtually any combination of cleavable covalent bonds, metal ion co-ordination or noncovalent bonds. The first example of molecular imprinting of organic network polymers introduced by Wulff was based on a covalent attachment strategy i.e. covalent monomer-template, covalent polymer-template [12]. 

Kempe M, Mosbach K. Chiral recognition of N alpha-protected amino acids and derivatives in non-covalently molecularly imprinted polymers. Int J Peptide Protein Res 1994 44 603 -606. 

Sellergren B (2001) The non-covalent approach to molecular imprinting. In Sellergren B (ed) Molecularly imprinted polymers. Man made mimics of antibodies and their applications in analytical chemistry. Elsevier, Amsterdam... 

Caro E et al (2002) Non-covalent and semi-covalent molecularly imprinted polymers for selective on-line solid-phase extraction of 4-nitrophenol from water samples. J Chromatogr A 963(1-2) 169-178... 

A novel approach to guest inclusion by dendrimers is the use of molecular imprinting . We will look at molecular imprinted polymers in more detail in Section 14.3. Generally the imprinting technique involves assembly of a covalent polymer - in this case dendrimer - about the target guest which acts... 

Covalent polymers can be imprinted with patterns from small guest molecules at the time of synthesis. These molecular Imprinted polymers (MIPs) are useful in sensing applications. 

Molecularly imprinted polymers (MIPs) for chiral separations have been prepared mainly by two approaches (i) covalent binding of the template to the functional monomer(s) and (ii) non-covalent binding (self-assembly) of the template and the functional monomer(s). 

The methylol and amino functional groups present in melamine resin are available for covalent attachment of antigens, antibodies, enzymes and other ligands of biological importance. Molecularly imprinted polymers that incorporate alkylated aminotriazines have been proposed for analytical purposes101. 

Figure 6.8 Overview of the preparation of a typical non-covalent molecular imprinted polymer.

The synthesis of a molecularly imprinted polymer is at first sight a straightforward affair. A template molecule, which can essentially be freely chosen, is mixed together with one or several polymerisable receptor molecules ( functional monomers ) [11-14] (Fig. 1). The latter, so-called binding sites, are selected on the basis of preferably strong and directed interactions with the template molecule to maximise the molecular fidelity of the imprinting process (covalent and non-covalent interactions are possible). This step... 

Molecularly imprinted polymers are impUcated for a wide range of apphca-tions. Their soHd-phase nature necessitates that the synthesis step includes the processing step. As is the case with any type of covalently crosslinked ma-... 

Molecularly Imprinted Polymers Molecular imprinting technique was recently used to prepare highly selective tailor-made synthetic affinity media used mainly in chromatographic resolution of racemates or artificial antibodies [158-161]. A complex between the template molecule and the functional monomer is first formed in solution by covalent or noncovalent interactions (Figure 6.12). 

Before the molecularly imprinted polymer may be used for rebinding studies, one step remains—extraction of the original template molecules from the polymer matrix. A number of extraction protocols have been developed for different imprinting procedures. In the covalent and metal coordination approaches, an appropriate reagent is needed to break the bonds formed between the template and the functional elements. For the noncovalent approach, a polar solvent, often... 

Wulff, G. Biflis, A. Molecular imprinting with covalent or stoichiometric non-covalent interactions. In Molecularly Imprinted Polymers—Man-Made Mimics of Antibodies and their Application in Analytical Chemistry Sellergren, B., Ed. Elsevier Amsterdam, 2001, 71-111 pp. 

Mukawa, T. Goto, T. Takeuchi, T. Post-oxidative conversion of thiol residue to sulfonic acid in the binding sites of molecularly imprinted polymers disulfide based covalent molecular imprinting for basic compounds. Analyst 2002,127, 1407-1409. 

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