Solid-phase extraction procedure

Beretta, G., Caneva, E., Regazzoni, L., Bakhtyari, N. G., and Facino, R. M. (2008). A solid-phase extraction procedure coupled to H-NMR, with chemometric analysis, to seek reliable markers of the botanical origin of honey. Anal. Chim. Acta 620,176-182. 

Sum-ez-Luque, S., Mato, I., Huidobro, J. F., and Simal-Lozano, J. (2002b). Solid-phase extraction procedure to remove organic acids from honey. /. Chromatogr. B 770, 77-82. 

Michalkiewicz A, Biesaga M and Pyrzynska K. 2008. Solid-phase extraction procedure for determination of phenolic acids and some flavonols in honey. J Chromatogr A 1187( 1-2) 18-24. 

The most common (off-line) sample preparation procedures after protein precipitation are solid phase extraction and liquid-liquid extraction. Multiple vendors and available chemistries utilize 96-well plates for solid phase extraction systems and liquid-liquid extraction procedures. Both extraction process can prepare samples for HPLC/MS/MS assay. Jemal et al.110 compared liquid-liquid extraction in a 96-well plate to semi-automated solid phase extraction in a 96-well plate for a carboxylic acid containing analyte in a human plasma matrix and reported that both clean-up procedures worked well. Yang et al.111 112 described two validated methods for compounds in plasma using semi-automated 96-well plate solid phase extraction procedures. Zimmer et al.113 compared solid phase extraction and liquid-liquid extraction to a turbulent flow chromatography clean-up for two test compounds in plasma all three clean-up approaches led to HPLC/MS/MS assays that met GLP requirements. 

Dai S. et al., 2005. Quantitation of sifuvirtide in monkey plasma by an online solid-phase extraction procedure combined with liquid chromatography/electrospray ionization tandem mass spectrometry. Rapid Commun Mass Spectrom 19 1273. 

Franke JP, de Zeeuw RA. 1998. Solid-phase extraction procedures in systematic toxicological analysis. J Chromatogr B 713 51. 

Huang Z-P, Chen X-H, Wijsbeek J, Franke J-P, de Zeeuw RA. 1996. An enzymic digestion and solid-phase extraction procedure for the screening for acidic, neutral, and basic drugs in liver using gas chromatography for analysis. J Anal Toxicol 20 248. 

Turiel E, Bordin G, Rodriguez AR (2005) Deteraiination of quinolones and fluoroquinolones in hospital sewage water by off-line and on-line solid-phase extraction procedures coupled to HPLC-UV. J Sep Sci 28 257-267... 

Solid-phase extraction procedures and quantitative analysis of aliphatic lactones in wine were described by Ferreira et al. [32] dealing with, among others, the quantitation of y-nonalactone and y-undecalactone at trace levels. 

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... 

Solid-phase extraction for milk, urine, and feces samples is carried out by washing the loaded Cig cartridge successively with 5 ml water, 5 ml acetone/ water (20 80), 5 ml methanol/water (20 80), 5 ml dichloromethane/hexane (20 80), and 5 ml ethyl acetate/hexane (10 90). The corticosteroids are eluted with 3 ml ethyl acetate. The eluate is evaporated, and the residual is reconstituted in 0.5 ml ethanol and 5 ml phosphate-buffered saline, pending subsequent immunoaffinity column cleanup. The solid-phase extraction procedure differs for liver samples. In that case, washing of the cartridge is performed with 5 ml water, 5... 

During recent years, however, the distinction between these two types of methods has become less clear because of the improved methods of sample cleanup that allow selective isolation of groups of compounds. Mixed-mechanism solid-phase extraction procedures and multi-immunoaffinity techniques are clear examples of liquid chromatographic developments that have contributed greatly to the current state of the art within residue analysis. 

Izatt, R. M., Review of selective ion separations at B YU using liquid membrane and solid phase extraction procedures, J. Incl. Phenom. Mol. Rec. Chem., 29, 197-220, 1997. 

By an improved solid-phase extraction procedure, 2-methyl-tetrahydro-furan-3-thiol 77 could be measured in wine at levels of 0.2 ng/L (01MI533, 08JC(A)9). This compound smells like strongly cooked meat, described as roasted meaty. From grape cultivars of the Vinho Verde region in Portugal 2-methyl-tetrahydrothiophen-3-one 78 was isolated (02ACA157). 

Motevalian et al. [62] developed a rapid, simple, and sensitive HPLC assay method for the simultaneous determination of omeprazole and its major metabolites in human plasma using a solid-phase extraction procedure. Eluent (50 /d) was injected on a /rBondapak Ci8 reversed-phase column (4.6 mm x 250 mm, 10 /un). The mobile phase consisted of 0.05 M phosphate buffer (pH 7.5) and acetonitrile (75 25) at a flow-rate of 0.8 ml/min. UV detection was at 302 nm. Mean recovery was greater than 96% and the analytical responses were linear over the omeprazole concentration range of 50-2000 ng/ml. The minimum detection limits were 10, 10, and 15 ng/ml for omeprazole, omeprazole sulfone, and hydroxyomeprazole, respectively. The method was used to determine the plasma concentration of the respective analytes in four healthy volunteers after an oral dose of 40 mg of omeprazole. 

The other form of on-line solid-phase extraction procedures involves column-switching techniques. Column switching employs valves that can be switched manually or automatically between a number of columns at predetermined times.67-69 For sample cleanup the analyte of interest is retained on the primary or precolumn while the interfering matrix components are eluted to waste. The analytes are then diverted to a second or analytical column where they are separated for identification and quantification. 

Jenkins KM, Young MS, Mallet CR, Elian AA (2004) Mixed-mode solid-phase extraction procedures for the determination of MDMA and metabolites in urine using LC-MS, LC-UV, or GC-NPD. J Anal Toxicol 28(l) 50-58... 

Application of LC-MS/MS techniques to the analysis of phthalate ester metabolites in urine have also been developed. For example, Blount et al. (2000b) have developed an assay to quantify the monoester metabolites (including MEHP) of eight phthalate diesters in urine, utilizing HPLC coupled with atmospheric pressure chemical ionization and tandem mass spectrometric (APCI-MS/MS) detection techniques. Urine samples were treated with -glucuronidase to release the free phthalate monoesters followed by a two-step solid phase extraction procedure. After evaporative concentration of the eluant, the analytes in the purified samples are further separated on a phenyl reverse phase HPLC column and quantified by APCI-MS/MS, following careful optizimation of the APCI-MS/MS instrument. The limits of detection for MEHP were determined to be 1.2 ng/ml urine with recovery efficiencies of between 78 and 91%. 

Bakhtiar R, Khemani L, Hayes M et al. (2002) Quantification of the anti-leukemia drug ST1571 (Gleevec) and ist metabolite (CGP 74588) in monkey plasma using a semi-automated solid phase extraction procedure and liquid chromatography-tandem mass spectrometry. J Pharm Biomed Anal 28(6) 1183-1194... 

The two most prevalent types of extraction procedures are (1) digestion of the hair matrix and extraction of the drug from the digest with liquid-liquid or solid-phase extraction procedures, or (2) extraction of the drug from the intact hair matrix. 

Tobiasz, A., Walas, S. Solid-phase-extraction procedures for atomic spectrometry determination of copper. Trends Anal. Chem. 62, 106-122 (2014)... 

Preliminary extraction of 5-HIAA may be used as an initial purification step before HPLC analysis. Organic solvents, anion-exchange resins, and other solid phase extraction procedures have aU been used. For many systems, direct injection of urine onto the analytical column is a common practice,and samples are often merely diluted with a buffer to protect the HPLC system from contamination. Methods that analyze 5-HIAA without prior sample cleanup rely on the selectivity of the HPLC separation combined with fluorescence or electrochemical detection to provide the requisite specificity. 

Bakhtiar, R. Khemani, L. Hayes, M. Bedman, T Tse, F. "Quantification of the Anti-Leukemia Drug ST1571 (Gleevec) and its Metabolite (CGP 74588) in Monkey Plasma Using a Semi-Automated Solid Phase Extraction Procedure and Liquid Chromatography-Tandem Mass Spectrometry, J. Pharm. Biomed. Anal. 28, 1183-1194 (2002). 

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