Sample introduction chromatography

P. Sandra (Ed.), Sample Introduction in Capillary Gas Chromatography, Vol 1, Chromatographic Method Series, Huethig, Basel, 1985. 

Z. Fiu and J. B. Phillips, Farge-volume sample introduction into narrow-hore gas chromatography columns using thermal desorption modulation and signal averaging , /. Microcolumn Sep. 2 33-40 (1990). 

The limited sample capacity and low carrier gas flow rates characteristic of open tubular column gas chromatography give rise to certain difl icultles in sample introduction. Direct sample... 

P. Sandra, (Ed.), "Sample Introduction in Capillary Gas Chromatography", Huethig, Heidelberg, Vol. 1, 1985. 

H.-G. Janssen, Sample Introduction Techniques for Capillary Gas Chromatography (Reference GI-12981), Gerstel Inc., Mulheim ad. Ruhr (1998). 

Principles and Characteristics As mentioned already (Section 3.5.2) solid-phase microextraction involves the use of a micro-fibre which is exposed to the analyte(s) for a prespecified time. GC-MS is an ideal detector after SPME extraction/injection for both qualitative and quantitative analysis. For SPME-GC analysis, the fibre is forced into the chromatography capillary injector, where the entire extraction is desorbed. A high linear flow-rate of the carrier gas along the fibre is essential to ensure complete desorption of the analytes. Because no solvent is injected, and the analytes are rapidly desorbed on to the column, minimum detection limits are improved and resolution is maintained. Online coupling of conventional fibre-based SPME coupled with GC is now becoming routine. Automated SPME takes the sample directly from bottle to gas chromatograph. Split/splitless, on-column and PTV injection are compatible with SPME. SPME can also be used very effectively for sample introduction to fast GC systems, provided that a dedicated injector is used for this purpose [69,70],... 

SFE-SFC operation consists of extraction, trapping, and transfer to the column for chromatography. Concentration of the solutes of interest before sample introduction to SFC may be achieved by ... 

The //PLC system described in this chapter is equipped with 24 parallel columns for liquid chromatography, each with its own sample introduction port and exit port for connection to detectors of choice (UV absorbance and/ or fluorescence). Flow from a binary solvent delivery system is divided evenly across 24 channels and results in 1/24 of the programmed pump flow rate through each column (i.e., total flow of 300 /zL/ min will produce a flow of 12.5 /zL/ min in each column). Samples are introduced to the columns by a multichannel autosampler configured to sample from either 96-or 384-well SBS standard plates. Figure 6.2 depicts a general view of the system. 

There are several sample introduction methods that are used in conjunction with ICP, including nebulization, electrothermal evaporation, gas chromatography, hydride generation, and laser ablation [30]. Laser ablation combined with ICP (LA-ICP) is useful for analysis of solids. In such a source the sample is positioned in a chamber prior to the ICP source, the ablation cell. Argon gas at atmosperic pressure flows through the cell towards the ICP source. The sample is irradiated by a laser beam and... 

Besides liquid samples, gases and solids can be analysed after making the appropriate modifications to the sample introduction system. The application of plasma sources as detectors for gas chromatography of metal complexes have teen reviewed by Uden Literature dealing with the analysis of gas and liquid chromatographic effluents have been surveyed by Carnahan et al. 

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