Solid molecular imprinted polymers

The most widely employed techniques for the extraction of water samples for triazine compounds include liquid-liquid extraction (LLE), solid-phase extraction (SPE), and liquid-solid extraction (LSE). Although most reports involving SPE are off-line procedures, there is increasing interest and subsequently increasing numbers of reports regarding on-line SPE, the goal of which is to improve overall productivity and safety. To a lesser extent, solid-phase microextraction (SPME), supercritical fluid extraction (SEE), semi-permeable membrane device (SPMD), and molecularly imprinted polymer (MIP) techniques have been reported. 

Among the techniques listed in Section 1.2.1, the two most documented approaches in addition to SPE, LLE, and PPT are solid phase microextraction (SPME) and affinity capture of analytes based on molecularly imprinted polymers (MIPs). Recent developments in these areas are briefly discussed below. 

L.I. Andersson, in Solid Phase Extraction on Molecularly Imprinted Polymers Requirements, Achievements and Future Work, S. Piletsky and A. Turner (Eds.), Landes Biosciences, New York, 2006. 

Currently, perhaps the most promising approach based on the use of molecularly imprinted polymers is solid phase extraction (SPE). Traditionally, when complex samples require a clean-up/enrichment step prior to high-resolution analysis,... 

Synthesis and Characterisation of Molecularly Imprinted Polymer Nanoparticles for Streptomycin for Use as Solid Phase Extraction Materials... 

W. M. Mullett, P. Martin, and J. Pawliszyn, In-Tube Molecularly Imprinted Polymer Solid-Phase Microextraction for the Selective Determination of Propranolol, Anal. Chem. 2001, 73, 2383 N. Masque, R. M. Marce, F. Borrull, P. A. G. Cormack, and D. C. Sherrington, Synthesis and Evaluation of a Molecularly Imprinted Polymer for Solid-Phase Extraction of 4-Nitrophenol from Environmental Water, Anal. Chem. 2000, 72, 4122. 

Abstract Most analytical applications of molecularly imprinted polymers are based on their selective adsorption properties towards the template or its analogs. In chromatography, solid phase extraction and electrochromatography this adsorption is a dynamic process. The dynamic process combined with the nonlinear adsorption isotherm of the polymers and other factors results in complications which have limited the success of imprinted polymers. This chapter explains these problems and shows many examples of successful applications overcoming or avoiding the problems. 

Andersson LI (2001) Selective solid-phase extraction of bio- and environmental samples using molecularly imprinted polymers. Bioseparation 10(6) 353—364... 

Masque N, Marce RM, Borrull F (2001) Molecularly imprinted polymers new tailor-made materials for selective solid-phase extraction. TrAC, Trends Anal Chem 20(9) 477 186... 

Tamayo FG, Turiel E, Martin-Esteban A (2007) Molecularly imprinted polymers for solid-phase extraction and solid-phase microextraction recent developments and future trends. J Chromatogr A 1152(l-2) 32 i0... 

Pichon V, Haupt K (2006) Affinity separations on molecularly imprinted polymers with special emphasis on solid-phase extraction. J Liq Chromatogr Related Technol 29(7—8) 989—1023... 

Caro E et al (2006) Application of molecularly imprinted polymers to solid-phase extraction of compounds from environmental and biological samples. TrAC, Trends Anal Chem 25(2) 143-154... 

Dias ACB et al (2008) Molecularly imprinted polymer as a solid phase extractor in flow analysis. Talanta 76(5) 988-996... 

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... 

Koeber R et al (2001) Evaluation of a multidimensional solid-phase extraction platform for highly selective on-line cleanup and high-throughput LC-MS analysis of triazines in river water samples using molecularly imprinted polymers. Anal Chem 73(11) 2437-2444... 

Chapuis F et al (2004) Retention mechanism of analytes in the solid-phase extraction process using molecularly imprinted polymers - application to the extraction of triazines from complex matrices. J Chromatogr B Anal Technol Biomed Life Sci 804(1) 93-101... 

Cobb Z, Sellergren B, Andersson LI (2007) Water-compatible molecularly imprinted polymers for efficient direct injection on-line solid-phase extraction of ropivacaine and bupivacaine from human plasma. Analyst 132(12) 1262—1271... 

STEVENSON D (1999), Molecular imprinted polymers for solid-phase extraction , Trends Anal Chem, 18, 154-159. 

While the above-described sorbents are essentially nonspecific and designed to allow extraction of a wide range of analytes, there are also sorbent phases that are selective toward individual analytes, or at least classes of analytes. These are immunoaffinity (IA) sorbents and molecularly imprinted polymers (MIPs). In the first case, antibodies are immobilized on the solid support used for extraction, and the selective (in the ideal case specific) biochemical interactions allow an antigen to bind selectively to the antibody, whereas the other sample constituents are not retained and... 

Zhu, Q. Z., P. Degelmann, R. Niessner, and D. Knopp. 2002. Selective trace analysis of sulfonylurea herbicides in water and soil samples based on solid-phase extraction using a molecularly imprinted polymer. Environ. Sci. Technol. 36 5411-5420. 

Caro, E., R.M. Marce, P.S.G. Cormack, D.C. Sherrington, and F. Borrull. 2003. On-line solid-phase extraction with molecularly imprinted polymers to selectively extract substituted 4-chlorophenols and 4-nitrophenol from water. J. Chromatogr. A 995 233-238. 

Mosbach and co-workers developed a method to prepare molecularly imprinted polymers by precipitation polymerization [24]. They started from a dilute, homogenous solution of the monomer methacrylic acid (MAA) and the crosslinker trimethylolpropane trimethacrylate (TRIM) or ethylene glycol dimethacrylate (EGDMA). The polymer formed in the presence of the template molecule 17/1-estradiol, theophylline, or caffeine contained a high proportion of discrete spheres of diameter less than a micron. Because the effect of coalescence becomes predominant with higher solid content of the reaction mixture, this approach is limited to solid contents of typically <2 wt%. 

Sellergren, B. (2001) Molecularly imprinted polymers in solid-phase extractions. In Lanza, F. (Ed.) Molecularly Imprinted Polymers-Man-made Mimics of Antibodies and Their Applications in Analytical Chemistrf. Techniques and Instrumentation in Analytical Chemistry, Vol. 23, Elsevier, Amsterdam, NL. 

Polymer libraries are covered according to their numerous applications, each described through a specific example. The reported examples include libraries of copolymers as liquid/solid supports with different compositions, libraries of biodegradable materials for clinical applications, libraries of stationary phases for GC/LC separations, libraries of polymeric reagents or catalysts, libraries of artificial polymeric receptors or molecularly imprinted polymers, and libraries of polymeric biosensors. The opportunities that could arise in the near future from novel applications of polymer libraries are also briefly discussed. 

Molecularly imprinted polymers in solid phase extractions... 

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