Sample preparation molecularly imprinted polymer

This section will illustrate the MIP technique for sample preparation by presenting examples of diazepam and its metabolites in hair samples.177 An anti-diazepam molecularly imprinted polymer... 

There are a host of new solid phases being brought to the market. Some of the most interesting currently include graphitized carbon, functionalized styrene-divinylbenzene copolymers, restricted access solid-phase reversed phase, affinity chromatography with antibodies, and molecular imprinted polymers. These five types of sorbents have different applications from environmental to biological sample preparation. 

G. Theodoridis, C.K. Zacharis, RD. Tzanavaras, D.G. Themelis, A. Economou, Automated sample preparation based on the sequential injection principle. Solid-phase extraction on a molecularly imprinted polymer coupled on-line to high-performance liquid chromatography, J. Chromatogr. A 1030 (2004) 69. 

Several SP materials have been used for the extraction of FRs from aqueous samples, plasma and milk (Table 31.7). Similar materials have been used for all FRs. Typical SP materials include Ci8 and Cg bonded to porous silica, highly cross-linked poly(styrene divinylbenzene) (PS-DVB), and graphitized carbon black (GCB). It is also possible to use XAD-2 resin for extraction of various FRs, pesticides, and plastic additives from large volumes of water (100 1). The analytes can then be either eluted from the resin by acetone hexane mixture, or Soxhlet extracted with acetone and hexane. For a specific determination of diphenyl phosphate in water and urine, molecularly imprinted polymers have been used in the solid phase extraction. The imprinted polymer was prepared using 2-vinylpyridine as the functional monomer, ethylene glycol dimethacrylate as the cross linker, and a structural analog of the analyte as the template molecule. Elution was done with methanol triethylamine as solvent. Also solid phase microextraction (SPME) has been applied in the analysis of PBDEs in water samples. The extraction has been done from a headspace of a heated water sample (100°C) using polydimethylsiloxane (PDMS) or polyacryl (PA) as the fiber material. ... 

Mohamed R, Richoz-Payot J, Gremaud E, Mottier P, YRmaz E, Tabet JC, Gut PA, Advantages of molecularly imprinted polymers LC-ESI-MS/MS for the selective extraction and quantification of chloramphenicol in milk-based matrixes. Comparison with a classical sample preparation. Anal. Chem. 2007 79 9557-9565. 

Other SPME-IMS methods that have been reported for application to pharmaceutical or related samples include those for analysis of ephedrine in urine, meth-amphetamines in human serum, and captopril in human plasma and pharmaceutical preparations. In a method similar to SPME-IMS, testosterone was collected with a molecular imprinted polymer from urine and desorbed into an IMS. The method was validated with HPLC and determined to have a detection limit of 0.9 ng/mL with a linear dynamic range from 10 to 250 ng/mL. ... 

B. Sellergren and A.-M. Esteban, Chapter 23 The use of molecularly imprinted polymers for sampling and sample preparation, in Handbook of Sample Preparation, eds. J. Pawliszyn, and H. L. Lord) John Wiley Sons, Hoboken, New Jersey, 2010, vol. 1, p. 445. 

Extraction and sample preparation are of importance in plant analysis. Clinic and forensic analyses usually rely on appropriate sample preparation to achieve a sufficiently low limit of detection. The pretreatment procedure before the chromatographic measurement must ensure exhaustive extraction of the analyte and removal of matrix that may interfere with analysis. Sample preparation methods for analysis of Catharanthus alkaloids include liquid-liquid extraction (LEE), supercritical fluid extraction (SEE), and molecularly imprinted polymers (MlPs)-based extraction. 

SPE is an exhaustive and almost solvent-free sample preparation technique. Typically, a tube is filled with a sorbent, which can be porous particles or a polymerized monolith. Various interactions are used to extract analytes from complex samples. Many of the commercially available SPE systems are for single use, but some, like RAM (restricted access materials) and MIP (molecular imprinted polymers), are typically obtained as reusable extraction devices. As will be discussed in detail, the extraction sorbents mainly function as normal phase, reversed phase, cation exchange, anion exchange, or a combination of these. 

E. Turiel and A. Martin-Esteban, Molecularly imprinted polymers for sample preparation A review. Anal. Chim. Acta, 668 (2) 87-99,2010. 

WM. Mullett, M. Walles, K. Levsen, ]. Borlak and ]. Pawliszyn, Multidimensional on-line sample preparation of verapamil and its metabolites by a molecularly imprinted polymer coupled to liquid chromatography-mass spectrometry, /. Chromatogr. B, 801 (2) 297-306, 2004. 

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