Development of non-aqueous single stage derivatisation method for the determination of putrescine and cadaverine using GC-MS

AbstractA single step derivatisation for the determination of putrescine and cadaverine by gas chromatography using trifluoroacetylacetone (TFAA) in methanol or ethanol was studied and optimised. The derivatives were analysed by an iontrap gas chromatograph-mass spectrometer (GC-MS) operating with electron impact ionisation with selective ion storage (EI-SIS) mode. The optimised mole ratios for TFAA/putrescine and TFAA/cadaverine reactions were 5/1 and 5.8/1 respectively with a reaction time of 15 minutes at 95oC. The retention times for the derivatised putrescine and cadaverine were 11.3 and 12.2 minutes respectively using the capillary column, CP-Sil 8CB; 30 m length x 0.25 mm i.d. x 0.25 mm film. The correlation coefficients (R2) of calibration curves for putrescine and cadaverine were 0.991 and 0.990 respectively over a concentration range of 100 ng cm−3 to 1500 ng cm−3. The method developed was found to be simple (single-stage derivatisation), rapid (15 minutes derivatisation & 14 minutes GC/MS run) and accurate (putrescine and cadaverine recoveries 94.8%–97.7%).

Download Full-text

Evaluation of a modified alcohol dehydrogenase assay for the determination of ethanol in blood.

Clinical Chemistry ◽

10.1093/clinchem/28.10.2125 ◽

1982 ◽

Vol 28 (10) ◽

pp. 2125-2127 ◽

Cited By ~ 42

Author(s):

A Poklis ◽

M A Mackell

Keyword(s):

Gas Chromatography ◽

Reaction Time ◽

Alcohol Dehydrogenase ◽

Correlation Coefficients ◽

Least Square ◽

Standard Curve ◽

Analytical Recovery ◽

Sigma Chemical ◽

Enzymic Assay

Abstract We evaluated a new alcohol dehydrogenase (EC 1.1.1.1) enzymic assay (ADH-glycine, Sigma Chemical Co.) for the determination of ethanol in blood. This assay differs from the manufacturer's previous assay (ADH-pyrophosphate) in that glycine replaces pyrophosphate as the buffer and hydrazine replaces semicarbazide as the trapping agent. The standard curve for the assay was linear over blood ethanol concentrations of 0.50-5.00 g/L. The reaction time of the assay was 10 min. At 1.00 g/L within-run and between-run CVs were 3.96% (n = 20) and 4.01% (n = 20), respectively. Mean analytical recovery of ethanol added to whole blood at 0.50-5.00 g/L was 99.7% (SD 2.6%). We performed 100 consecutive clinical and forensic determinations by the ADH-glycine assay, the ADH-pyrophosphate assay, and gas chromatography. Correlation coefficients of the results by least-square linear regression were 0.995 for ADH-pyrophosphate vs ADH-glycine, and 0.990 for gas chromatography vs ADH-glycine. The major advantage of the ADH-glycine assay over the ADH-pyrophosphate assay is the shorter reaction time, 10 min vs 30 min.

Download Full-text

Determination of volatile alcohols and acetone in serum by non-polar capillary gas chromatography after direct sample injection.

Clinical Chemistry ◽

10.1093/clinchem/30.10.1672 ◽

1984 ◽

Vol 30 (10) ◽

pp. 1672-1674 ◽

Cited By ~ 16

Author(s):

N B Smith

Keyword(s):

Gas Chromatography ◽

Capillary Gas Chromatography ◽

Capillary Column ◽

Internal Standard ◽

Fused Silica ◽

Gas Chromatograph ◽

Ionization Detector ◽

Flame Ionization ◽

Split Ratio

Abstract In this method for detection and quantification of volatile alcohols by capillary gas chromatography, the serum sample is deproteinized, then directly injected into the gas chromatograph with 1-propanol as the internal standard. The capillary column is a 30-m bonded methylsilicone-coated, fused-silica column. With helium as the carrier gas, the injector inlet is set at a split ratio of 1/30 and the average linear velocity in the column is 25 cm/s. Injector and flame-ionization detector temperatures are 280 degrees C, oven temperature 35 degrees C. Chromatography time is less than 3 min.

Download Full-text

Determination of Residues of Eight Synthetic Pyrethroids in Tobacco by Capillary Gas Chromatography

Beiträge zur Tabakforschung International/Contributions to Tobacco Research ◽

10.2478/cttr-2013-0633 ◽

1994 ◽

Vol 16 (2) ◽

pp. 65-75

Author(s):

BS Dattilo ◽

S Gallo ◽

G Lionetti

Keyword(s):

Gas Chromatography ◽

Film Thickness ◽

Stationary Phase ◽

Capillary Gas Chromatography ◽

Capillary Column ◽

Limit Of Detection ◽

Synthetic Pyrethroids ◽

Gas Chromatograph ◽

Limit Of Determination

AbstractA method was developed for the simultaneous determination of the residues of the following eight synthetic pyrethroids and their isomers in tobacco: tetramethrin, permethrin, cyfluthrin, cypermethrin, alfamethrin, flucythrinate, fluvalinate and deltamethrin. The pesticides were extracted from ground tobacco by means of acetone:water 9:1 for 5 hours. The extract was diluted with water and partitioned into n-hexane. The organic phase was concentrated to about 1 ml and then purified by a Florisil-SPE column. The gas-chromatographic analyses were run with a gas-chromatograph Carlo Erba Series Mega HRGC 5300 equipped with a capillary column (stationary phase OV-1 - 0.10-0.15 µm film thickness, 25 m long) and a 63Ni electron-capture detector. Two different injection ports were used: split-splitless and cold split-splitless, working both with isothermal and programmed temperatures. Both the limit of detection and the limit of determination were estimated for each compound. Recoveries from fortified samples at level of 1 µgKg-1 are reported.

Download Full-text