Solid-phase extraction procedure optimization

Ferreira V, Jarauta I, Ortega L, Cacho J (2004) Simple strategy for the optimization of solid-phase extraction procedures through the use of solid-liquid distribution coefficients—application to the determination of aliphatic lactones in wine. J Chromatogr A 1025 147 Rettinger K, Karl V, Schmarr HG, Dettmar F, Hener U, Mosandl A (1991) Chirospecific analysis of 2-alkylbranched alcohols, -acids, and -esters chirality evaluation of 2-methylbutanoates from apples and pineapples. Phytochem Anal 2 184... 

Wennrich [167] optimised important accelerated solvent extraction parameters, such as extraction temperature and time, using a spiked wetland soil. The effect of small amounts of organic modifiers on the extraction yields was studied. An extraction temperature of 125 °C and ten-minute extractions performed three times proved optimal. Two accelerated solvent extraction-solid-phase microextraction procedures without and with an organic modifier (5% acetonitrile) were evaluated with respect to precision and detection limits. 

Capella-Peiro et al. (28) used a 3 full factorial design to optimize the capillary zone electrophoresis (CZE) separation of a group of seven antihistamines (brompheniramine, chlorpheniramine, cyproheptadine, diphenhydramine, doxylamine, hydroxyzine, and loratadine). In this case, critical parameters such as pH (a concentration of 20 mM phosphate was kept constant in all the experiments) and the applied voltage were studied to evaluate their effect on the resolution and efficiency. Maximum response was achieved at pH 2.0 and an applied voltage of 5 kV. After a repeatability study to check the precision of the electrophoretic method, as well as a suitable calibration, the usefulness of this optimized method was demonstrated through the determination of the listed histamines in pharmaceuticals, urine, and serum samples (recoveries were in agreement with the stated contents). Urine samples were diluted and directly injected in the CE system, while serum samples were previously extracted by means of a solid-phase extraction (SPE) procedure. 

Analytical quantification of BAs may be difficult due to the complexity of some food matrices and the low concentrations of BAs generally encountered in the majority of foodstuffs. In addition, the low volatility of these compounds and the lack of chromophores for most of the BAs, does not allow the rapid direct detection by ultraviolet and visible (UV and vis) spectrometric or fluorimetric (FL) methods. In general, in order to obtain an optimal analysis, extraction, clean-up, concentration, and derivat-ization procedures are required. Extraction methods usually based on liquid-liquid or solid-phase extraction with C18 or ion-exchange cartridges can be applied to improve selectivity and sensitivity (Giannotti et al., 2008 Pena-Gallego, Hemdndez-Orte, Cacho, Ferreira, 2009). Alternative approaches, such as solid-phase microextraction... 

Matrix solid-phase extraction (MSPE) is a recently introduced alternative to SPE in which samples are thoroughly mixed with a solid substrate, then packed into a column and washed and eluted with solvents, so the sample cleanup and analytes extraction are carried out in a single step. The solid support can be CIS- or C8-bonded silica ° 2 or Amberlite XAD-2, and even the use of sea sand as solid substrate has also been reported recently. As in the traditional chromatographic and SPE procedures, extraction conditions, especially the composition of the eluents, need to be optimized before the extraction. 

Optimization of Solid-Phase Extraction-Gas Chromatography Procedure... 

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