Miniaturized solid-phase extraction

In this design, on-column sample enrichment is incorporated into the sheathless interface (Janini et al., 2003). A miniaturized solid-phase extraction (mSPE) cartridge, made of reversed-phase material, was attached to the CE capillary near the injection end as shown in Fig. 16.1. 

Saito, Y., Nakao, Y, Imaizumi, M., Morishima, Y, Kiso, Y, and Jinno, K., Miniaturized solid-phase extraction as a sample preparation technique for the determination of phthalates in water. Analytical and Bioanalytical Chemistry, 373, 81-86, 2002. 

Ekstrom, S., Wallman, L., Hok, D., Marko-Varga, G, and Laurell, T., Miniaturized solid-phase extraction and sample preparation for MALDl MS using a microfabricated integrated selective enrichment target. Journal Proteome Research, 5, 1071-1081, 2006. 

Figure 3.3 Sample preparation by miniaturized solid-phase extraction or affinity enrichment. The resin is used to trap the analyte and serves to concentrate and desalt...

Mogensen, O., Christensen, R., Vach, W Jorgensen, P.E., and Jensen, O.N. (2005) Serum protein profiling by miniaturized solid-phase extraction and matrix-assisted laser desorption/ionization mass spectrometry. Rapid Commun. Mass Spectrom., 19,1578-1586. 

Fig. 3 Schematic workflow of porous silicon-ISET iMALDI top (I), antibody-immobilized porous silicon was used to capture the antigen angiotensin I bottom (II), RP solid-phase extraction sample preparation protocol on the ISET chip was used to purify and reconcentrate the elution followed by MALDI MS deteetion (Yan et al. 2011) (Reprinted with permission from Analytical Chemistry, 83, Yan, Ahmad-Tajudin, Bengtsson, Xiao, Laurell, Ekstrom, Noncovalent antibody immobilization on porous silieon eombined with miniaturized solid-phase extraction SPE) for array based immunoMALDI assays, 4942-4948. Copyright 2011 Ameriean Chemieal Society)...

Yan H, Ahmad-Tajudin A, Bengtsson M, Xiao S, Laurell T, Ekstrom S (2011) Noncovalent antibody immobilization on porous silicon combined with miniaturized solid-phase extraction (SPE) for array based immunoMALDI assays. Anal Chem 83 4942-4948... 

Saito, Y., M. Imaizumi, T. Takeichi, and K. Jinno. 2002. Miniaturized fiber-in-tube solid-phase extraction as the sample preconcentration method for microcolumn liquid-phase separations. Anal. Bioanal. Chem. 372 164-168. 

An innovative way to perform a sample cleanup that is fast, accurate, and easy, is the use of solid-phase extraction (SPE) columns. In many ways these devices resemble miniature HPLC columns upon which a preseparation is done. Using these minicolumns for sample clean-up eliminates many of the drawbacks associated with traditional liquid-liquid extraction, such as (1) the use of large amounts of expensive organic solvent, (2) low recovery due to solvent emulsion formation, and (3) large requirements for labor, time, glassware, and bench space. 

Solid-phase extraction (SPE) (Fig. 6) is a miniature version of the liquid chromatography experiment. It was commercialized and introduced in the late 1970s. With the availability of prepacked cartridges, SPE first became popular in the mid-1980s [19]. It has been widely applied to sample cleanup in the drug discovery... 

One more trend that is worth mentioning is the miniaturization of sample preparation techniques. Solid phase microextraction is one good example of where very small samples are consumed and very small extracts are produced. Solid phase extractions can also be scaled down by reducing the bed volume or by use of coated membranes. Likewise liquid-liquid extractions can be scaled down conserving both sample and solvent. 

Immunoaffinity solid-phase extraction An antibody attached to a solid material is used to bind the compounds of interest Optimization of the binding and elution and miniaturization of this type of sample cleaning have been applied for CE and LC. 

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