Extraction cartridge

Solid-phase extraction cartridges (a) disk cartridge (b) column cartridge. 

Patrone, /. thimble, shell (for extractions) cartridge pattern stencil mandrel die collet. 

The solid phase extraction cartridge (SPEC) is another somewhat vainglorious name given to a short inert plastic tube packed with an adsorbent, usually a reversed phase or an ion exchange resin. The particle size of the packing is often significantly larger than that used... 

The tetrahydrocannabinol carboxylic acid was extracted from the urine by means of a solid state extraction cartridge packed with a Cl 8 reverse phase (octyldecyldimethyl chains). As the urine sample was used direct, and contained no added solvent, the materials of interest were irreversibly adsorbed on the reverse phase solely by dispersive interactions. 

Another interesting example of the use of solid state extraction cartridges is the determination of the tricyclic antidepressant drugs in blood serum (2). 

This sample preparation involved, firstly, an extraction and the elimination of the solid matrix by filtration and, secondly, a concentration procedure employing a solid phase extraction cartridge. The compounds of interest were separated solely by dispersive interactions with the reversed phase. In the example given, the corn meal was spiked with the aflatoxins. 

Fifty grams of the corn meal was blended with 100 ml of an 80% methanol 20% water mixture for about a minute and the corn meal removed by filtration. The extraction cartridge was packed with a bonded phase carrying cyanopropylmethyl chains that would exhibit... 

This analysis depends on the use of a solid phase extraction cartridge to concentrate the herbicides directly from the pond water and the... 

A new technique has been developed to analyze a- and (3-endosulfan concentrations in human urine (Vidal et al. 1998). Samples are mixed with a buffer solution and then passed through solid phase extraction cartridges for analysis using gas chromatography-tandem mass spectrometry (GC-MS-MS). 

Betalains are vacuolar plant pigments. Hence their hydrophilic nature is comprehensible. Although they are slightly soluble in ethanol and methanol, water is the best snited solvent both for stability and solnbility reasons. In contrast to the antho-cyanins, the betalains are even more polar as can be demonstrated by shorter retention times in RP-HPLC and lower solubilities in alcoholic solutions. The varying polarities may also be beneficially used to separate anthocyanins from betalains on an RP-18 solid-phase extraction cartridge (Stintzing, unpublished data). 

ASPEC Automated sample preparation with extraction cartridges... 

The use of extraction cartridges is one example of a technique known as column switching (it is also often called multidimensional chromatography). The method can be used, either on-line... 

The use of extraction cartridges in the separation of azines, discussed in the last Section, is an example of on-column concentration using off-line column switching. A chromatogram can be cut off-line by collecting the zones of interest at the detector outlet followed by reinjection of the collected fraction onto a secondary column. The mobile phases used with the two columns should be compatible, eg they should be miscible and the mobile phase used with the first column should not have too high an eluting power in the second column. If the mobile phases are incompatible it may be possible to evaporate the primary mobile phase and redissolve the sample in a suitable solvent. 

Direct elution of analyte from extraction cartridge into LC system... 

Datta et al. [40] used pressurised fluid extraction to extract ground fish tissue, and the resulting extract was purified on aminopropyl silica (APS) extraction cartridges. With no further sample preparation, NP and its ethoxylates, up to nonylphenol pentaethoxylate, were quantified using normal phase (APS Hypersil) HPLC with fluorescence detection. 

Other techniques to improve throughput are instrumentation based and may involve multiple HPLC systems. The simplest method involves the automated use of solid phase extraction cartridges for sample cleanup followed by direct injection into the mass spectrometer [114], Coupling of multiple HPLC systems to one mass spectrometer allows one column to equilibrate and separate while another column to flow into the mass spectrometer. Multiple HPLC systems may be configured such that the mass spectrometer is only exposed to each serial HPLC eluent as the analyte of interest is eluted [115,116]. Although multiple H P LC-based methods may increase throughput, they also typically decrease sensitivity and may confound data workup and interpretation. 

Lopez-Avila V, Milanes J, Dodhiwala NS, et al. 1989. Cleanup of environmental sample extracts using florisil solid-phase extraction cartridges. J Chromatogr Sci 27(5) 209-220. 

Abu Ruz S, Millership J, Heaney L, McElnay J. 2003. Simple liquid chromatography method for the rapid simultaneous determination of prednisolone and cortisol in plasma and urine using hydrophilic lipophilic balanced solid phase extraction cartridges. J Chromatogr B Biomed Sci Appl 798(2) 193-201. 

Molins-Legua C, Campinc-Falco P, Sevillano-Cabeza A, Ped-r6n-Pons M. 1999. Urine polyamines determination using dansyl chloride derivatization in solid-phase extraction cartridges and HPLC. Analyst 124 477-482. 

Theobald N. 1988. Rapid preliminary separation of petroleum hydrocarbons by solid-phase extraction cartridges. Anal Chim Acta 204(1-2) 135-144. 

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