On-line digestion

Environmental waters As, Bi, Hg, Pb, Sn KBr03-KBr-HCl Prolabo Maxidigest MX-350 On-line digestion FI-CV- AAS, HG-AAS 27... 

Wurl, O., O. Elsholz, and J. Baasner. 2000. Monitoring of total Hg in the river Elbe FIA-device for on-line digestion. Fresenius J. Anal. Chem. 366 191-195. 

For the multispecies determination of a maximum of four species like inorganic Hg2+, Me-Hg, ethyl-Hg, and phenyl-Hg an automatic system was devised based on the on-line coupling of HPLC with CV-AFS via a postcolumn MW digestion. The digestion medium was K2S208 in HC1. Parameters influencing on-line digestion efficiency and the separation effects were optimized, which allowed for the separation of the four Hg species within 13 min. The absolute LoDs were 0.3 ng for Hg2+, 0.2 ng for Me-Hg, 0.17 ng for ethyl-Hg, and 0.14 ng for phenyl-Hg+ [63]. 

Perhaps the current fascination for using microwave heating for on-line digestion has led to the introduction of commercial instruments based on this hybrid technique [42],... 

Gluodenis, T.J., Tyson, J.E. Elow injection systems for directly coupling on-line digestion with analytical atomic spectrometry. Part 1. Dissolution of cocoa under stopped-flow, high-pressure conditions. J. Anal. At. Spectrom. 7, 301-306 (1992)... 

Fig. 5.6. (A) Flow-injection manifold for the wet digestion of shellfish slurry samples C carrier solution, P peristaltic pump, 1C injector commutator, W waste, r restrictor. (B) Dynamic manifold for the analysis of sludge slurries in an on-line digestion-reduction system by Fl-HG-AFS IV injection valve, AFS atomic fluorescence spectrometer, P peristaltic pump. (Reproduced with permission of the Royal Society of Chemistry.)...

The greatest advantage of on-line digestion methods over batch methods is that they minimize the problem of acid fumes produced during the digestion of biological samples in the traditional Teflon vessels used in batch treatments. Gas evolution in the on-line methods, however, can lead to problems resulting in pressure build-up and disturbances... 

The tiypsin IMER can be applied either in off-line [38] or on-line mode [47] with ESI-MS, or with SPE-LC-MS [42, 45], or as part of a multidimensional online system (Ch. 17.5.4). The on-line digestion by means of a tiypsin IMER can be performed either in flow-through mode or in stop-flow mode [46]. Systems consisting of a trypsin IMER and an SPE-LC-MS system were reported for on-line digestion and peptide mapping of lactate dehydrogenase [42]. 

G. Vecchione, B. Casetta, R. Santacroce, M. Margaglione, A comprehensive on-line digestion-IC-MS-CID-MS approach for the characterization of human fibrinogen. Rapid Commun. Mass Spectrom., 15 (2001) 1383. 

E. Calleri, C. Temporini, E. Perani, C. Stella, S. Rudaz, D. Lubda, G. MeUerio, J. -L. Veuthey, G. Caccialanza, G. Massolini, Development of a bioreactor based on trypsin immobilized on monolithic support for the on-line digestion and identification of proteins, J. Chromatogr. A, 1045 (2004) 99. 

For the determination of the Hg species methylmercury, phenylmercury and Hg(ll), ozone was used successfully in a batch cold-vapor system [126]. The preconcentration and speciation of Cr(lll) and Cr(VI) in water sample can be performed using solid-phase extraction (SPE) [105]. An SPME (solid-phase microextraction) technique has been used as the sample preparation system for the innovative simultaneous multielement/multi-species determination of six different mercury, tin. and lead species in waters and urine with GC/MS-MS [141], [142], The determination of arsenic species [As(III), As(V), MMA. DMA, arsenocholine, arsenobetaine)] has also been shown to work with an on-line digestion step prior to hydride generation AAS [125] (see Fig. 7). 

Open tubular capillary microreactor Trypsin Covalent linking IMER in fused silica capillaries integrated with nano-electrospray emitter trypsin immobilized on surface of the inner wall of the fused silica capillary tubing fast on-line digestion and peptide mass mapping of angiotensin II, Cyt-C, haemoglobin, and p-casein [118]... 

Monolith capillary microreactor Pepsin A Entrapment Pepsin-encapsulated film was prepared by a sol-gel method on-line digestion of insulin chain beta and lysozyme 100% recovery for insulin chain (3-amino acid sequence 73% recovery for the lysozyme amino acid sequence [139]... 

Zhao s group also integrated an immobilized enzyme microreactor in fused silica capillaries with a nanoelectrospray mass spectrometry for on-line digestion and fast peptide mass mapping [118]. Trypsin was immobilized onto the surface of the inner... 

Chen Y, Wu M, Wang K, Chen B, Yao S, Zou H, Nie L (2011) Vinyl functionalized silica hybrid monolith-based trypsin microreactor for on line digestion and separation via thiol-ene chck strategy. J Chromatogr A 1218(44) 7982-7988... 

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