Combinatorial molecularly imprinted polymers

Takeuchi, T., Fukuma, D., and Matsui, J., Combinatorial molecular imprinting an approach to synthetic polymer receptors, Anal. Chem., 71, 285, 1999. 

To overcome the problem of their limited range of applicability and to extend the spectrum of application other than to the imprint molecule, molecularly imprinted polymer combinatorial libraries for multiple simultaneous chiral separations have been prepared [ 191 ], demonstrating that the ligand cross-reactivities of molecularly imprinted polymers can be beneficially employed for the simultaneous separation of different stereoisomeric structures. 

In another attempt, cyclopeptide SOs and SO libraries, respectively, for CE enan-tioseparations have been developed by combinatorial chemistry approaches [378,379], and recently also molecularly imprinted polymer combinatorial libraries have been prepared [ 191 ]. 

Ramstrom, O., Ye, L., Krook, M., Mosbach, K. Screening of a combinatorial steroid library using molecularly imprinted polymers Anal. Comm., 1998, 35, 9-11... 

El-Toufaili, F.A., Visnjevski, A., Briiggemann, O. Screening combinatorial libraries of molecularly imprinted polymer films casted on membranes in single-use membrane modules J. Chromatogr., B, 2004, 804, 135-139... 

Villoslada, F. N. Takeuchi, T., Multivariate analysis and experimental design in the screening of combinatorial libraries of molecular imprinted polymers, Bull. Chem. Soc. Jpn. 2005, 78, 1354-1361. 

Atrazine MAA 2-sulfoethylaminomethacrylate EDMA CHCI3 Combinatorial molecular imprinting for atrazine-decomposing polymers [177]... 

Takeuchi T, Fukuma D, Matsui J et al. Combinatorial molecular imprinting for formation of atrazine decomposing polymers. Chem Lett 2001 30 530-531. 

This chapter aims to provide an update on the role of anions as templates. The review is divided in two main sections (a) anion-templated synthesis of assemblies linked together by irreversible bonds (or bonds that are inert under mild experimental conditions) (b) anion templates in systems where the bonds linking the components are reversible and lead to anion-controlled dynamic combinatorial libraries. Since some comprehensive reviews in the area of anion temptation have appeared over the past few years [5-7], this chapter will mainly focus on papers published recently and will aim to show the principles of anion temptation rather than being a comprehensive account of the literature. In addition, the scope of the chapter will be restricted to finite assemblies (molecular or supramolecular) and not polymeric (for a review on molecularly imprinted polymers using anions see Steinke s chapter in this volume). 

The use of anions as templating agents is discussed by Vilar. The chapter starts with a general overview of the area and a discussion of the applications of anion templates in organic and coordination chemistry. The second part of the chapter deals with examples where anions are employed as templates in dynamic combinatorial libraries. This approach promises to provide an efficient route for the synthesis of better and more selective anion receptors. The last chapter by Ewen and Steinke also deals with the use of anions as templates but in this case in the context of molecular imprinted polymers. The first half of the chapter provides an introduction into molecularly imprinted polymers and this is followed by a detailed discussion of examples where anionic species have been used to imprint this class of polymeric materials. 

Bowman, M. Allender, C. Heard, C. Brain, K. Molecularly imprinted polymers as selective sorbents for the preliminary screening of combinatorial libraries. J. Mater. Sci. and Eng. C-Biomi Mater. Sens. Syst. 1998, 25, 37-43. 

Lanza, F., and Sellergren, B. (2004). Molecularly imprinted polymers via high-throughput and combinatorial techniques,... 

Examples of this technique are described for artificial receptors for the alkaloid yohimbine binding peptides obtained from a phage display library [57], for the steroid libraries related to lla-hydroxyprogesterone [58], corticosterone [58] (reported in Fig. 12), and cortisol [59]. A molecularly imprinted polymer working as a synthetic receptor for a series of chiral benzodiazepines [47], artificial receptors for the tricyclic antidepressant drug nortriptyline—obtained by covalent and noncovalent molecular imprinting and studied by capillary liquid chromatography with a simulated combinatorial library [60,61]—were also examined. 

No successful example has been reported so far using a TSA in a dynamic combinatorial approach to transition metal catalyst selection. However, inspired by enzymes and molecular cages, molecularly imprinted polymers were successfully developed by WuUF et al. and in a small number of cases directed towards transition metal catalysis [22]. Cavities as biomimetic catalysts are created by generation of polymeric materials in the presence of a TSA as a template, which is removed after polymerization. In the presence of the substrate, the incorporation of the catalyst precursor leads to high activities, the transition state being stabilized by the polymeric cavities. 

Takeuchi and co-workers (18) coupled combinatorial techniques with molecular imprinted polymers to develop sensors for triazine herbicides. The library consisted of a 7 x 7 array containing different fractions of monomers methacrylic acid (MAA) and 2-(trifluoromethyl)acrylic acid (TFMAA) with constant concentrations of the imprint molecules ametryn or atrazine. After UV-initiated polymerization, the products from the sensor library were characterized by HPLC measurement of herbicide concentration. The receptor efficiency was observed to vary with monomer type the atrazine receptor efficiency increased with MAA composition and the ametryn receptor was enhanced by increased fractions of TFMAA. Although only monomer concentration was varied in the hbraries, the authors conclude that the CM synthetic approach would be usefiil in analyzing other variables such as solvent, cross-linking agent, and polymerization conditions to produce optimum molecularly imprinted polymer sensors. 

F.Y. Huangfu, B. Wang and Y. Sun, Preparation of molecularly imprinted polymer based on combinatorial imprinted for recognition of norfloxacin, Polym-Plast Technol, 52 (10) 957-963,2013. 

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