Solid-phase extraction automated

Pharmacokinetics Quantitative bioanalysis Selected ion monitoring Selected reaction monitoring Automated off-line solid-phase extraction Automated on-line extraction Fouda et al., 1991 Wang-Iverson et al., 1992 Covey et al., 1986 Kaye et al., 1992 Allanson et al., 1996 Simpson et al., 1998 Needham et al., 1998... 

Figure 2.12 Schematic representation of an on-line SPE-GC system consisting of three switching valves (VI-V3), two pumps (a solvent-delivery unit (SDU) pump and a syringe pump) and a GC system equipped with a solvent-vapour exit (SVE), an MS instrument detector, a retention gap, a retaining precolumn and an analytical column. Reprinted from Journal of Chromatography, AIIS, A. J. H. Eouter et al, Analysis of microcontaminants in aqueous samples hy fully automated on-line solid-phase extraction-gas chromatography-mass selective detection , pp. 67-83, copyright 1996, with permission from Elsevier Science.

H. M. M. Arafa, E. M. A. Hamada, M. M. A. Elzamai and H. Nau, Eully automated detemination of selective retinoic acid receptor ligands in mouse plasma and tissue by reversed-phase liquid chi omatography coupled on-line with solid-phase extraction , 7. Chromatogr. A 729 125-136 (1996). 

J. A. Pascual and J. Sanagustin, Eully automated analytical method for codeine quantification in human plasma using on-line solid-phase extraction and high-perfomance liquid clrromatogi aphy with ulti aviolet detection , 7. Chromatogr. B 724 295-302 (1999). 

J. Huwyler, S. Rufer, E. Kusters and J. Drewe, Rapid and highly automated determination of moipliine and moipliine glucuronides in plasma by on-line solid-phase extraction and column liquid cliromatography , 7. Chromatogr. B 674 51-63 (1995). 

O. V. Olesen and B. Poulsen, On-line fully automated deteimination of clozapine and desmethylclozapine in human semm by solid-phase extraction on exchangeable car-ti idges and liquid cliromatography using a methanol buffer mobile phase on unmodified silica , 7. Chromatogr. 622 39-46 (1993). 

G. Garcia-Encina, R. Eaixan, S. Puig and E. Maitinez, Validation of an automated liquid cliromatogi aphic method for omeprazole in human plasma using on-line solid-phase extraction , 7. Pharm. Biomed. Anal. 21 371-382 (1999). 

P. R. Kootstr-a and H. A. Herbold, Automated solid-phase extraction and coupled-column reversed-phase liquid cliromatogr aphy for the trace-level determination of low-molecular-mass carbonyl compounds in ak , 7. Chromatogr. 697 203-211 (1995). 

S. Lacorte, J. J. Vreuls, J. S. Salau, R Ventura and D. Barcelo, Monitoring of pesticides in river water using fully automated on-line solid-phase extraction and liquid cliro-matography with diode array detection with a novel filrtation device , J. Chromatogr. 795 71-82(1998). 

Postigo C, Lopez De Alda MJ, Barcelo D (2008) Fully automated determination in the low nanogram per liter level of different classes of drugs of abuse in sewage water by on-line solid-phase extraction-liquid chromatography-electrospray-tandem mass spectrometry. Anal Chem 80(9) 3123-3134... 

Solid phase extraction (SPE) is a very simple, rapid and reproducible cleanup technique that is now widely accepted as an alternative to the time-consuming liquid-liquid extractions. Additionally, SPE uses relatively small volumes of solvents, and is easy to automate. It is available in a number of different formats, including cartridges, disks, loose material, well plates or SPME using film-coated capillaries. SPE can be considered as an extraction technique when used for isolation and concentration or a cleanup technique when used to remove co-extractives from solvent extracts. The use of SPE for cleanup is discussed later. 

There are basically three methods of liquid sampling in GC direct sampling, solid-phase extraction and liquid extraction. The traditional method of treating liquid samples prior to GC injection is liquid-liquid extraction (LLE), but several alternative methods, which reduce or eliminate the use of solvents, are preferred nowadays, such as static and dynamic headspace (DHS) for volatile compounds and supercritical fluid extraction (SFE) and solid-phase extraction (SPE) for semivolatiles. The method chosen depends on concentration and nature of the substances of interest that are present in the liquid. Direct sampling is used when the substances to be assayed are major components of the liquid. The other two extraction procedures are used when the pertinent solutes are present in very low concentration. Modem automated on-line SPE-GC-MS is configured either for at-column conditions or rapid large-volume injection (RLVI). 

Lopez-Sema R, Perez S, Ginebreda A, Petrovic M, Barcelo D (2010) Fully automated determination of 74 pharmaceuticals in environmental and waste waters by online solid phase extraction-liquid chromatography-electrospray-tandem mass spectrometry. Talanta 83(2) 410 124... 

Riu et al. [542] has reported the determination of linear ethyl benzane-sulfates in coastal waters using automated solid-phase extraction followed by capillary electrophoresis with ultraviolet detection, and confirmed by capillary electrophoresis-mass spectrometry. The detection limits were 1 pg/1 when 250 ml of coastal water was preconcentrated. 

Kuster M, de Alda MJL, Barata C, Raldua D, Barcelo D (2008) Analysis of 17 polar to semi-polar pesticides in the Ebro river delta during the main growing season of rice by automated on-line solid-phase extraction-liquid chromatography-tandem mass spectrometry. Talanta 75(2) 390-401... 

The analyses of illicit drugs and metabolites in the sampled waters were performed following a previously described and validated fully automated method based on on-line solid phase extraction-liquid chromatography-tandem mass spectrometry (on-line SPE-LC-MS/MS) [19]. 

Analysis of pesticides in water was performed by fully automated online solid-phase extraction-liquid chromatography-tandem mass spectrometry (SPE-LC-MS/ MS) [25, 31]. These pesticides (a total of 22 belonging to the classes of triazines, OP, chloroacetanilides, phenylureas, thiocarbamates, acid herbicides, and anilides) were selected on the basis of previously published studies [20, 25], information gathered from the water authorities, and known use in rice crops. 

Kampioti AA, da Cunha ACB, de Alda ML et al (2005) Fully automated multianalyte determination of different classes of pesticides, at picogram per litre levels in water, by online solid-phase extraction-liquid chromatography-electrospray-tandem mass spectrometry. Anal Bioanal Chem 382 1815-1825... 

Solid Phase Sorbents. Solid Phase Extraction Formats. Automated Solid Phase Extraction. Solid Phase Microextraction. Applications of SPE and SPME. 

Application of SPE to sample clean-up started in 1977 with the introduction of disposable cartridges packed with silica-based bonded phase sorbents. The solid phase extraction term was devised in 1982. The most commonly cited advantages of SPE over liquid-liquid extraction (LLE) as practiced on a macroscale include the reduced time and labor requirements, use of much lower volumes of solvents, minimal risk of emulsion formation, selectivity achievable when desired, wide choices of sorbents, and amenability to automation. The principle of operation consists of four steps (1) conditioning of the sorbent with a solvent and water or buffer, (2) loading of the sample in an aqueous or aqueous low organic medium, (3) washing away unwanted components with a suitable combination of solvents, and (4) elution of the desired compound with an appropriate organic solvent. 

Conditions for Automated Solid Phase Extraction of Vitamin D Metabolite from Plasma after Protein Precipitation... 

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. 

Davies, I.D., Allanson, J.P., and Causon, R.C. 1999. Rapid determination of the anti-cancer drug chlorambucil (Leukeran) and its phenyl acetic acid mustard metabolite in human serum and plasma by automated solid-phase extraction and liquid chromatography-tandem mass spectrometry. J. Chrom-matogr. B. 732 173. 

Bourgogne E., Grivet C., and Hopfgartner G., 2005. Determination of talinolol in human plasma using automated online solid phase extraction combined with atmospheric pressure chemical ionization tandem mass spectrometry. J Chromatogr B 820 103. 

Lacorte S. and Barceld D., 1995. Determination of organophosphorus pesticides and their transformation products in river waters by automated online solid-phase extraction followed by thermospray liquid chromatography. J Chromatogr A 712 103. 

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