Solid-phase extraction , MIPs

LLE, liquid-liquid extraction SPE, solid-phase extraction MIP, molecularly imprinted polymers sorbent. 

FAo formic acid, SPE solid-phase extraction, MIPs molecular imprinted polymers, RP-HPLC reverse-phase high-perf mance liquid chromatograjAty, RP-UPLC reveree-i ase ultraperformance liquid chromatography, AcN acetonitrile, MeOH methanol, ESI electrospray, QqQ triple quadrupole, QqLIT quadrupole-linear ion trap, SRM selective-reactum monitorii mode, Rec Analyte recovery, LOD limit of detection. 

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. 

A recent review by Pichon and Haupt169 summarizes the progress in the area of utilization of MIPs for sample preparation purposes and cites several examples of solid phase extraction (MISPE) from biological matrices. The requirements and applications of MIPs are reviewed in a recent book170 and other literature.171-176... 

Keywords Catalysis, Capillary electrochromatography, MIP, Polymer, Sensor, Solid phase extraction... 

As mentioned above, most MIPs are synthesized in organic solvents to preserve the hydrogen and electrostatic interactions between template and monomer. However, for the application to solid-phase extraction (SPE) where the target is most of the time in water samples or in biological fluids, a lot of studies have been carried out to examine the influence of binding media parameters (solvent polarity and composition, buffer pH, concentration, ionic strength, etc.) with the aim of attenuating non-specific adsorption of the analyte due to hydrophobic interactions which predominate in such media. For a recent review, see Tse Sum Bui and Haupt [95]. 

Up to now, most efforts have been directed towards the preparation of uniformly sized spherical MIP particles in the micrometre range. This is the obvious consequence of the need for this kind of materials as fillers for high-performance chromatographic columns, capillaries for electrophoresis, cartridges for solid-phase extractions and other applications requiring selective stationary phases. Additionally though, strategies for the preparation of other more sophisticated MIP forms, such as membranes, (nano)monoliths, films, micro- and nanostructured surfaces etc. 

Recently, a method for preparing MIP monolithic columns for electrophoresis, chromatography and solid-phase extraction has been developed, which uses a preformed polymeric monolith, onto which an MIP with specific recognition sites is subsequently grafted [149, 179-181]. 

Although potentially useful for sample preparation by solid-phase extraction, monolithic MIP phases had initially only been applied as stationary phase for LC... 

Chromatography, Solid-Phase Extraction, and Capillary Electrochromatography with MIPs... 

Solid-Phase Extraction with MIPs (MISPE). 276... 

The majority of papers written on MIPs deal with their testing or application in a chromatographic, solid-phase extraction (SPE), or capillary electrochromatography (CEC) system. Many excellent reviews have been written in the last decade on such MIP systems [1-29]. These reviews discuss the large variety of templates used, the polymerization strategies, the formats of the separation system, and the optimization of the separation process. In earlier years there were only very few applications on real samples to be reported. This has changed recently and reviews are also becoming available on this topic [30]. 

An application of molecular imprinting in drug bioanalysis closer to practical realisation is probably that of solid phase extraction (SPE). This application does not suffer to the same extent from the drawbacks generally associated with MIPs, such as peak broadening in liquid chromatography and leakage of imprint mole-... 

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