Chromatography with Spectrometric Detection

First method the leaching was carried out with 10 mL NaOH (0.5 mol L )-Na2C03 (0.3 mol L ) buffer and agitation in a heated ultrasonic bath (70 °C) for 40 min. The leachate was diluted with HC03 /H2C03 buffer and filtered over a 0.45 pm membrane filter. Separation was carried out by ion chromatography using columns of Dionex lonpac AG-7-AS 7 [mobile phase  

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Th. Hankemeier, Automated Sample Preparation and Large-Volume Injection for Gas Chromatography with Spectrometric Detection, Ph.D. thesis, 2000, Free University Amsterdam, Netherlands. 

Gas chromatography and high-performance liquid chromatography with NP detection [326-328], photoionisation detection and mass spectrometric detection [329-332] have all been used in general surveys of pesticides in insecticides in soils. 

Hauser, B., M. Schellin, and P. Popp. 2004. Membrane-assisted solvent extraction of triazines, organochlorine, and organophosphorus compounds in complex samples combined with large-volume injection-gas chromatography/mass spectrometric detection. Anal. Chem. 76 6029-6038. 

Matthias et al. [216] have described a comprehensive method for the determination of aquatic butyltin and butylmethyltin species at ultratrace levels using simultaneous sodium borohydride hydridisation, extraction with gas chromatography-flame photometric detection and gas chromatography-mass spectrometric detection. The detection limits for a lOOmL sample were 7ng L 1 of tin for tetrabutyltin and tributyltin, 3ng L 1 of tin for dibutyltin and 22ng L 1 tin for monobutyltin. For 800mL samples detection limits were l-2ng L 1 tin for tri- and tetrabutyltin and below lng L 1 tin for dibutyltin. The technique was applied to the detection of biodegradation products of tributyltin in non saline waters. 

Wang, K.D., Chen, P.S., Huang, S.D. Simultaneous derivatization and extraction of chloro-phenols in water samples with up-and-down shaker-assisted dispersive liquid-liquid microextraction coupled with gas chromatography/mass spectrometric detection. Anal. Bioanal. Chem. 406, 2123-2131 (2014)... 

Wong, J.W., Webster, M.G., Halverson, C.A., Hengel, M.J., Ngim, K.K., and Ebeler, S.E. (2003) Multiresidue pesticide analysis in wines by solid-phase extraction and capillary gas chromatography-mass spectrometric detection with selective ion monitoring,/. Agric. Food Chem., 51(5), 1148-1161. 

Biomonitoring methods are available for chemicals commonly used in laboratories. For example, a common laboratory solvent, toluene, can be measured directly in blood, and its metabolite, hippuric acid, can be measured in urine. Collection of urine samples is often favored because it is not an invasive procedure and does not require a needle stick. Urine is treated with acid and extracted with an organic solvent and the organic layer containing the hippuric acid is separated and dried. The hippuric acid is converted to a derivative that is suitable for gas chromatography with flame ionization detection or mass spectrometric detection, or alternatively the underivatized hippuric acid is measured by liquid chromatography with ultraviolet detection or mass spectrometric detection. 

According to this bottom-up approach, the (somewhat arbitrary) minimum number of IPs that must be obtained for the confirmation of regulated substances is proposed (European Commission 2002) to be three, but for positive identification of banned compounds the number is increased to four in order to decrease the risk of false positives examples of IPs for various combinations are shown in Table 9.3. For banned substances at least some IPs earned by mass spectrometry are mandatory but, since some analytes do not yield a sufficient number of ions, other techniques can be used to contribute a maximum of one IP each, including LC coupled with full scan diode array spectrophotometer (DAD) or with fluorescence detection or immunochemical detection, or two-dimensional thin-layer chromatography (TLC) coupled with spectrometric detection. 

Gu M, Su ZG, Janson JC (2006) The separation of polyphenols by isociatic hydrogen braid adsorption chromatography on a cross-linked 12 % agarose gel. Chromatographia 64 247-253 Klejdus B, Vacek J, Benesova L, Kopecky J, Lapcik O, Kuban V (2007) Rapid-resolutirai HPLC with spectrometric detection for the determination and identification of isoflavraies in soy preparations and plant extracts. Anal Bioanal Chem 389 2277-2285... 

For off-bead analysis, coupling between chromatographic separation and mass spectrometric detection has proven especially powerful. The combination between high performance liquid chromatography (HPLC) and electrospray ionisation mass spectrometry has the advantage that purity of product mixtures can be coupled on-line with the product identification. 

The ion spray liquid chromatography/mass spectrometry (LC-MS) interface coupled via a postsuppressor split with an ion chromatography (IC) has been used in the analysis of alcohol sulfates. The IC-MS readily produces the molecular weight while the tandem mass spectrometric detection IC-MS-MS provides structural information [305]. 

Revilla, 1. et al.. Identification of anthocyanin derivatives in grape skin extracts and red wines by liquid chromatography with diode array and mass spectrometric detection, J. Chromatogr. A, 847, 83, 1999. 

Kugler, F. et ah. Determination of free amino compounds in betalainic fruits and vegetables by gas chromatography with flame ionization and mass spectrometric detection, J. Agric. Food Chem., 54, 4311, 2006. 

Gas chromatography coupled with mass spectrometric detection has also been applied to the detection of... 

Selley et al. (1992) have recently employed gas chromatography combined with mass spectrometric detection to determine levels of the cytotoxic monounsaturated aldehyde 4-hydroxy-/7 t-2-nonenal in the blood plasma of healthy human subjects, and patients with rheumatoid and osteoarthritis. Intriguingly, this lipid peroxidation end-product is present at a concentration ofc. lx 10 mol/dm in healthy and osteoarthritic human plasma samples (but significantly elevated in those collected from rheumatoid arthritis patients). Although at least some of this could originate from the oxidative degradation of PUFAs invm, there may be a relationship existing between these levels and the frequency of thermally/... 

Creed JT, and Brockhoff CA (1999) Isotope dilution analysis of bromate in drinking water matrixes by ion chromatography with inductively coupled plasma mass spectrometric detection. Anal Chem 71 722-726. 

Confirmation of suspected residue findings relies on the various chromatographic principles of cleanup and determination (GPC, NP-LC, GC), and is further supported by re-analysis of the final extract(s) on a GC stationary phase of different polarity, providing modified selectivity, or by the use of GC with specific mass spectrometric detection [GC/MS or gas chromatography/tandem mass spectrometry (GC/MS/MS)]. 

Zheng, J., Kosmus, W., Pichler-Semmelrock, F., and Kock, M., Arsenic speci-ation in human urine reference materials using high-performance liquid chromatography with inductively coupled plasma mass spectrometric detection, /. Trace Elements Med. Biol., 13, 150, 1999. 

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