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LCGC Europe-03-01-2009

LCGC Europe

Practical Aspects of Solvent Extraction

March 01, 2009

Sample Preparation Perspectives

22

3

Columnist Ron Majors discusses some of the practical considerations in the successful application of the popular yet age-old technique of solvent extraction (also known as liquid–liquid extraction, or LLE). After a brief review of the basics, guidelines on the selection of the appropriate extraction solvents and how to use acid–base equilibria to ensure efficient extractions of ionic and ionizable compounds are provided. Problems in LLE and the solutions to these problems are highlighted. A newer technique called dispersive liquid–liquid microextraction (DLLME) is introduced.

Development of a Miniature Gas Chromatograph (µCAD) with Sample Enrichment, Programmed Temperature GC and Plasma Emission Detection (PED)

March 01, 2009

Regular article

22

3

A miniature gas chromatograph incorporating a miniaturized chemical trap for enrichment, rapid thermal desorption of the trap, a resistively heated capillary column for programmed GC analysis and a micro-chip-based plasma emission detector (PED) is described. The sampling and chromatographic conditions for the analysis of volatile compounds in air are presented. The performance of the µCAD is illustrated in the universal (carbon) mode and for the selective detection of chlorinated and organo-mercury compounds. Detection limits (DLs) are at the sub-μg/L level in the carbon mode and 10 ng/L for organo-mercury compounds.

Sixty Years of Pittcon

March 01, 2009

Regular article

22

3

Pittcon celebrates 60 years of service to the scientific community and remains an unmissable event in the analytical chemistry calendar.

Optimizing Detector Set-up and Operating Conditions

March 01, 2009

GC Connections

22

3

Detectors are another link in the chain of signals that a chromatographic analysis generates. After separation, a detector transduces the chemical signals of eluted analytes to an electrical signal that is then recorded and measured. The identities and amounts of analytes are determined from this information. This month in "GC Connections", John Hinshaw examines the environment, set-up and operating conditions necessary to ensure high gas chromatography detector performance and reliability.