Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Liquid chromatography trace enrichment

Noroozian E, Maris FA, Nielen MWF, et al. 1987. Liquid chromatographic trace enrichment with on-line capillary gas chromatography for the determination of organic pollutants in aqueous samples. Journal of High Resolution Chromatography and Chromatography Communications 10 17-24. [Pg.308]

Figure 5.3 Analysis of 100 ml of (a) surface water and (b) drinking water sample spiked with 0.1 pig/ml of microcystins, using column-switching HPLC 1, microcystin-RR 2, microcystin-YR 3, microcystin-LR. Reprinted from Journal of Chromatography A, 848, H. S. Lee et al, On-line trace enrichment for the simultaneous determination of microcystins in aqueous samples using high performance liquid chromatography with diode-array detection , pp 179-184, copyright 1999, with permission from Elsevier Science. Figure 5.3 Analysis of 100 ml of (a) surface water and (b) drinking water sample spiked with 0.1 pig/ml of microcystins, using column-switching HPLC 1, microcystin-RR 2, microcystin-YR 3, microcystin-LR. Reprinted from Journal of Chromatography A, 848, H. S. Lee et al, On-line trace enrichment for the simultaneous determination of microcystins in aqueous samples using high performance liquid chromatography with diode-array detection , pp 179-184, copyright 1999, with permission from Elsevier Science.
Multidimensional liquid chromatography encompasses a variety of techniques used for seunple separation, cleanup and trace enrichment [12,279-289]. A characteristic feature of these methods is the use of two or more columns for the separation with either manual or automatic switching by a valve interface of fractions between columns. These techniques require only minor modification to existing equipment, and of equal importance, enable the sample preparation and separation procedures to be completely automated. [Pg.411]

Asperger A. et al., 2002. Trace determination of priority pesticide in water by means of high-speed online solid-phase extraction-liquid chromatography-tandem mass spectrometry using turbulent-flow chromatography columns for enrichment and a short monolithic column for fast liquid chromatographic separation. J Chromatogr A 960 109. [Pg.293]

Pocurull E, Marce RM, Borrull F. 1996. Determination of phenolic compounds in natural waters by liquid chromatography with ultraviolet and electrochemical detection after on-line trace enrichment. J Chromatogr 738 1-9. [Pg.223]

P. Kotianova and E. Matisova, Liquid-phase microextraction and its utilization for trace analysis of organic compounds in water matrix. Chemicke Listy, 2000,94(4), 220-225. Liu Jf, Chi Yg, Jiang Gb, C. Tai, Peng Jf and JT. Hu, Ionic liquid-based liquid-phase microextraction, a new sample enrichment procedure for liquid chromatography. Journal of Chromatography A, 2004,1026(1-2), 143-147. [Pg.121]

Following initial sample extraction, the primary extract must frequently be subjected to some kind of further cleanup including liquid-liquid partitioning, diphasic dialysis, solid-phase extraction, matrix solid-phase dispersion, immunoaffinity chromatography cleanup, liquid chromatography cleanup, or online trace enrichment. In some instances, some of these procedures are used in combination in order to attain higher purification levels. [Pg.889]

Liquid chromatography cleanup on a LiChrosorb Diol column has been further proposed for the offline purification of chloramphenicol residues from bovine muscle and eggs (32). An online approach based on reversed-phase principles has also been described for isolation of chloramphenicol residues from swine kidney by an automated column switching system (63). Use of a protein exclusion column (Hisep) has been also suggested in an online trace-enrichment method for the determination of chloramphenicol in animal tissues (52). By employing a column-switching system, all chloramphenicol that eluted from the protein exclusion column was trapped at the entry of a 5 m Supelcosil LC-18 preconcentration column, to be subsequently back-flashed into the analytical column. [Pg.890]

Using mentioned extraction/deproteinization procedures, the obtained aqueous or organic extracts often represent very dilute solutions of the analyte(s). These extracts may also contain coextractives that, if not efficiently separated prior to analysis of the final extract, will increase the background noise of the detector making it impossible to determine the analyte(s) at the trace residue levels likely to occur in the analyzed samples. Hence, to reduce potential interferences and concentrate the analyte(s), the primary sample extracts are often subjected to some kind of additional sample cleanup such as liquid-liquid partitioning, solid-phase extraction, or online trace enrichment and liquid chromatography. In many instances, more than one of these cleanup procedures may be applied in combination to allow higher purification of the analyte(s). [Pg.906]

Tire aqueous or organic extract obtained at this point may be a very dilute solution containing interfering compounds and making it difficult to determine trace level concentrations of the analyte(s) of interest. To reduce interferences and concentrate the analyte(s), the primary sample extract is furiher subjected to various types of sample cleanup procedures such as conventional liquid-liquid partitioning, solid-phase extraction, matrix solid-phase dispersion, online trace enrichment, liquid chromatography, online dialysis and subsequent trace enrichment, and supercritical fluid extraction. In most cases some of Urese procedures are used in combination to obtain highly purified extracts. [Pg.962]

Miller, J. W. Garrison, A. W. Rogers, L. B. A General Approach to the Analysis of Water for Nonvolatile Organics by Precolumn Trace Enrichment High Performance Liquid Chromatography to be published. [Pg.141]

F Maris, R Geerdink, R Frei, U Brinkman. On-line trace enrichment for improved sensitivity in liquid chromatography with direct liquid introduction mass spectrometric detection. J Chromatogr 323 113-120, 1985. [Pg.714]

C. Lipschitz, H. Irth, G. J. de Jong, U. A. Th Brinkman and R. W. Frei, Trace enrichment of pyrimidine nucleobases, 5-fluoro-uracil and bromacil on a silver-loaded thiol stationary phase with on-line reversed-phase high-performance liquid chromatography , J. Chromatogr. 471 321-334 (1989). [Pg.298]

H. Irth, R. Tocklu, K. Welten, G. J. de Jong, R. W. Frei and U. A. Th Brinkman, Trace enrichment on a metal-loaded thiol stationary phase in liquid chromatography effect of analyte structure and pH value on the (de)sorption behaviour , J. Pharm. Biomed. Anal. 7 1679-1690(1989). [Pg.298]

Figure 13.13 On-line trace enrichment-RPLC-diode-array detection (DAD) chromatogram (at 230 nm) obtained from 200 ml of tap water spiked with various pesticides at levels of 1 jxg L1. Reprinted from Chromatographia, 43, C. Aguilar et al., Determination of pesticides by on-line trace enrichment-reversed-phase liquid chromatography-diode-array detection and confirmation by particle-beam mass spectrometry , pp. 592-598,1996, with permission from Vieweg Publishing. Figure 13.13 On-line trace enrichment-RPLC-diode-array detection (DAD) chromatogram (at 230 nm) obtained from 200 ml of tap water spiked with various pesticides at levels of 1 jxg L1. Reprinted from Chromatographia, 43, C. Aguilar et al., Determination of pesticides by on-line trace enrichment-reversed-phase liquid chromatography-diode-array detection and confirmation by particle-beam mass spectrometry , pp. 592-598,1996, with permission from Vieweg Publishing.
R. M. Marce, H. Prosen, C. Crespo, M. Calull, F. Borrull and U. A. Th Brinkman, Online trace enrichment of polar pesticides in environmental waters by reversed-phase liquid chromatography-diode array detection-particle beam mass spectrometry , J. Chromatogr. 696 63-74 (1995). [Pg.374]

Gerike P., H. Klotz, J.G.A. Kooijman, E. Matthijs, and J. Waters. 1994. The determination of dihard-ened tallowdimethyl ammonium compounds (DHTDMAC) in environmental matrices using trace enrichment techniques and high performance liquid chromatography with conductometric detection. Water Res. 28, 147-154. [Pg.465]

Barcelo, D., G. Durand, V. Bouvot, and M. Nielen (1993). Use of extraction disks for trace enrichment of various pesticides from river water and simulated seawater samples followed by liquid chromatography-rapid-scanning UV-visible and thermospray-mass spectrometry detection. Environ. Sci. Technol., 27(2) 271-277. [Pg.262]

Schonmann and Kern [33] have used on-line enrichment for microgram per litre analysis of PAHs in water by high performance liquid chromatography. The trace enrichment method is based on the affinity of non polar pollutants for reversed phase chromatography supports. [Pg.108]

Cassidy and Elchuk [287,288] carried out trace enrichments and high performance liquid chromatography of solutions of nickel, cobalt, copper,... [Pg.145]


See other pages where Liquid chromatography trace enrichment is mentioned: [Pg.44]    [Pg.836]    [Pg.109]    [Pg.422]    [Pg.426]    [Pg.734]    [Pg.382]    [Pg.401]    [Pg.402]    [Pg.922]    [Pg.545]    [Pg.551]    [Pg.111]    [Pg.907]    [Pg.1031]    [Pg.1032]    [Pg.109]    [Pg.131]    [Pg.298]    [Pg.261]    [Pg.345]    [Pg.150]    [Pg.66]   
See also in sourсe #XX -- [ Pg.117 , Pg.118 , Pg.119 , Pg.120 , Pg.121 , Pg.122 ]

See also in sourсe #XX -- [ Pg.117 , Pg.118 , Pg.119 , Pg.120 , Pg.121 , Pg.122 ]




SEARCH



Trace enrichment

© 2024 chempedia.info