Automated gas chromatographic

Nokihara K, Gerhardt J Development of an improved automated gas-chromatographic chiral analysis system application to non-natural amino acids and natural protein hydrolysates. Chirality 2001 13 431. 

Szathmary and Luhmann [50] described a sensitive and automated gas chromatographic method for the determination of miconazole in plasma samples. Plasma was mixed with internal standard l-[2,4-dichloro-2-(2,3,4-trichlorobenzyloxy) phenethyl]imidazole and 0.1 M sodium hydroxide and extracted with heptane-isoamyl alcohol (197 3) and the drug was back-extracted with 0.05 M sulfuric acid. The aqueous phase was adjusted to pH 10 and extracted with an identical organic phase, which was evaporated to dryness. The residue was dissolved in isopropanol and subjected to gas chromatography on a column (12 m x 0.2 mm) of OV-1 (0.1 pm) at 265 °C, with nitrogen phosphorous detection. Recovery of miconazole was 85% and the calibration graph was rectilinear for 0.25 250 ng/mL. 

The feed gas flow rate was monitored and controlled by mass flow controllers. Product gases were fed through heated stainless steel lines to a sample loop in an automated gas chromatograph. The GC analysis was performed using two isothermal columns (80°C) in series, a Porapak T and a Molecular Sieve 5A column. When necessary, a second GC analysis using a temperature programmed Hayesep R column was used to separate and detect small hydnx arbons (such as ethylene and ethane) and H2O. 

Yokouchi, Y H. Bandow, and H. Akimoto, Development of Automated Gas Chromatographic-Mass Spectrometric Analysis for Natural Volatile Organic Compounds in the Atmosphere, J. Chromatogr., 642, 401-407 (1993). 

Automation. Gas chromatographs may be used to monitor automatically various chemical processes in which samples may be periodically taken and injected onto a column for separation and detection. 

J. Yeung, G. Baker, et al., Simple automated gas chromatographic analysis of amino acids and its application to brain tissue and urine, J. Chromatogr., 378 293-304 (1986). 

J. E. Haky and T. M. Stickney, Automated gas chromatographic method for the determination of residual solvents in bulk pharmaceuticals, J. Chromatogr., 321 137 (1985). 

Mallet et al. [174] used an automated gas chromatographic system which consisted of a gas chromatograph mounted with an automatic sample interfaced to an integrator. A Melpar flame photometric detector (phosphorus mode) was connected with the flame gas inlets in the reverse configuration to prevent solvent flame-out. The detector was... 

Reaction studies were carried out in a specially designed infrared cell which doubled as a flow reactor [10]. Before a given experiment, the catalyst was pressed into the form of a thin wafer, placed into the reactor cell, and reduced at 200-450°C for twenty hours. The catalyst was then run to steady-state in 3.4% CO and 0.8% NO for sixteen hours before any steady-state data were obtained. All data were obtained under differential reactor conditions and analysis of the feed and product gases was accomplished using an automated gas chromatographic system [11],... 

Dowty, B.L., Green, L.E. and Laseter, J.L., 1976. Automated gas chromatographic procedure to analyze volatile organics in water and biological fluids. Anal. Chem., 48 946— 949. 

Automated Gas Chromatographic Procedure to Analyze Volatile Organics in Water and Biological Fluids Anal. Chem. 48(6) 946-949 (1976) CA 84 176072y... 

An Assay for Diphenoxylic Acid in Urine Using an Automated Gas Chromatograph Mass Spectrometer system Quant. Mass Spectrom. Life Sci. 2 287-293 (1978) CA 91 13346w... 

Hauch, G., and Terfloth, H. P. Automated Gas Chromatographic Investigation in Regards to Routine Blood Alcohol Analysis... 

Rambeck, B., and Meijer, J. W. Comprehensive Method for the Determination of Antiepileptic Drugs Using a Novel Extraction Technique and a Fully Automated Gas Chromatograph... 

Automated Gas Chromatographic Analysis of Phenylalanine in Serum Clin. Biochem. 5(3) 166-170 (1972)... 

Yamamoto N, Okayasu H, Murayama S, Mori S, Hunahashi K, Suzuki K. Measurement of volatile organic compounds in the urban atmosphere of Yokohama, Japan, by an automated gas chromatographic system. Atmos Environ. 2000 34 4441-6. 

Chai et al. (46) developed a novel automated gas chromatographic technique to study slow kinetic processes. The technique uses multiple headspace extraction and can be applied to reactions involving volatile formation or adsorp-tion/desorption phenomena. 

FIGURE 13.14 Typical mstnimeiit sch atic (a) and chromatogram (b) for the automated gas chromatographic analysis of coal liquefaction gases. Column lA 18 ft—27% bis (EE) A + 3.5% Carbowax 1540 + 6.5% DC 200/500 mesh. Column 1C 12 in. on Chromosorb P-AW 60/80 mesh. Column IB 3 ft—OPN/Porasil C 80/100 mesh. Column 2 6 ft—80% Porapak N + 20% PORAPAK Q 50/50 mesh. Column 3 7 ft—molecular sieve 13 x 45/60 mesh. Column 4 6 ft—8% OV-101 on Chromosorb W-AWDMCS, 80/100 mesh. (Reprinted with permission from Reference 56, Journal of Chromatographic Science, Cop)night 1982, Preston Publications, A Division of Preston Industries, Inc.)... 

Several attempts have also been conducted to develop portable GC for PAHs monitoring. Several sorbents can also be used as selective concentrators for sample air as part of the analysis protocol for air taken fix)m canisters or air sampled directly by automated gas chromatographs (autoGCs), which is essentially equivalent to ambient air monitoring. However, these autoGCs have not been quite successful up to date for PAHs in air monitoring. 

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