Search results for "Gas Chromatography"
showing 10 items of 750 documents
Detection of 9-Tetrahydrocannabinol and Amphetamine-Type Stimulants in Oral Fluid Using the Rapid Stat Point-of-Collection Drug-Testing Device
2010
The Rapid Stat assay, a point-of-collection drug-testing device for detection of amphetamines, cannabinoids, cocaine, opiates, methadone, and benzodiazepines in oral fluid, was evaluated for cannabis and amphetamine-type stimulants. The Rapid Stat tests (n = 134) were applied by police officers in routine traffic checks. Oral fluid and blood samples were analyzed using gas chromatography-mass spectrometry (GC-MS) for Delta(9)-tetrahydrocannabinol, amphetamine, methamphetamine, methylenedioxymethamphetamine, methylenedioxyethylamphetamine, and methylenedioxyamphetamine. The comparison of GC-MS analysis of oral fluid with the Rapid Stat results for cannabis showed a sensitivity of 85%, a spec…
Influence of Pigmentation on the Codeine Content of Hair Fibers in Guinea Pigs
1997
Tortoise shell guinea pigs (n = 7) were administered codeine (1 mg/mL codeine-base) in their drinking water for 3 weeks. Black, reddish-brown and white hair was collected separately from each animal before and after treatment. The hair samples were analyzed by GC/MS. The experiment showed positive results for all hair fibers with large individual variability of drug incorporation. Low drug intake resulted in small differences of the drug content in hair fibers different in color, whereas in cases of high drug intake a strong influence of hair pigmentation on the analytical results was observed. The highest drug content was always found in black hair samples, non-pigmented hair showed the lo…
Incorporation and metabolism of trans 20∶5 in endothelial cells. Effect on prostacyclin synthesis
2000
To study the ability of long-chain trans fatty acids (FA) to be incorporated and metabolized into endothelial cells, bovine aortic endothelial cells were incubated with medium enriched eicosapentaenoic acid (EPA) bound to albumin (M2) or one of its geometrical isomers: 20:5 5c,8c,11t,14c,17c (M3), 20:5 5c,8c,11c,14c,17t (M4), or 20:5 5c,8c,11t,14c,17t (M5). After 48 h of incubation, supernatant and cells were harvested and their lipids were analyzed, including prostacyclin synthesis. EPA and 22:5n-3 of endothelial cells incubated with M2 were, respectively, three and two times higher than in control cells (incubated in M1, without any fatty acid added), whereas 22:6n-3 increased only in the…
Application of Gas Chromatography coupled with Mass Spectroscopy (GC/MS) to the analysis of archaeological ceramic amphorae belonging to the Carthagi…
2017
<p class="Abstract"><span lang="EN-US">The aim of this preliminary work was to identify characteristic compounds in 7 underwater marine ceramic amphorae sherds dating from the period of the battle of the Egadi Islands that decided the end of the First Punic War (241 B.C.) by Gas Chromatography coupled with Mass Spectroscopy (GC/MS).</span></p>
Thermodynamic Interaction Parameters of Tetra-n-undecylcalix[4]resorcinarenes with Selected Solvents Studied by Inverse Gas Chromatography
2004
The basic thermodynamic parameters, characterising intermolecular interactions of tetra-n-undecylcalix[4]resorcinarene and its octaacetate derivative with simple organic solutes, were calculated by using the inverse gas chromatography method. Free energy, enthalpy and entropy of sorption were determined.
Removal and fate of endocrine disruptors chemicals under lab-scalepostreatment stage. Removal assessment using light, oxygen and microalgae
2013
[EN] The aim of this study was to assess the effect of light, oxygen and microalgae on micropollutants removal. The studied micropollutants were 4-(1,1,3,3-tetramethylbutyl)phenol (OP), technical-nonylphenol (t-NP), 4-n-nonylphenol (4-NP), Bisphenol-A (BPA). In order to study the effect of the three variables on the micropollutants removal, a factorial design was developed. The experiments were carried out in four batch reactors which treated the effluent of an anaerobic membrane bioreactor. The gas chromatography mass spectrometry was used for the measurement of the micropollutants. The results showed that light, oxygen and microalgae affected differently to the degradation ratios of each …
A method for measuring low-weight carboxylic acids from biosolid compost
2006
Concentration of low-weight carboxylic acids (LWCA) is one of the important parameters that should be taken into consideration when compost is applied as soil improver for plant cultivation, because high amounts of LWCA can be toxic to plants. The present work describes a method for analysis of LWCA in compost as a useful tool for monitoring compost quality and safety. The method was tested on compost samples of two different ages: 3 (immature) and 6 (mature) months old. Acids from compost samples were extracted at high pH, filtered, and freeze-dried. The dried sodium salts were derivatized with a sulfuric acid–methanol mixture and concentrations of 11 low-weight fatty acids (C1–C10) were a…
Biological effects and photodegradation by TiO(2) of terpenes present in industrial wastewater.
2010
Abstract The aim of this work was to study the biological effects of four monoterpenes, i.e. α-pinene, β-pinene, 3-carene and d -limonene present in the wastewater of a citrus transformation factory. The study was carried out by exposing V79 Chinese hamster cells to single terpene or to the mixture of four terpenes at concentrations corresponding to those in the wastewater evaluated by head space solid phase micro extraction and gas chromatography (HS-SPME-GC) analyses. Treatments with single or combined terpenes similarly affected cell vitality, but only the combined treatments induced the 6-thioguanine resistant mutants. Moreover the photocatalytic degradation of the four terpenes was suc…
Chlorinated short chain aliphatic hydrocarbons in pine needles by purge and trap gas chromatography/mass spectrometry
1995
The concentrations of volatile chlorinated short chain aliphatic hydrocarbons in pine needles have been measured using purge and trap GC/MS. The concentrations of dichloromethane, chloroform, dichloroethene and tetrachloroethene in the needles were calculated. The concentrations of dichloromethane and tetrachloroethene were highest. As a rule the concentrations were higher in the older needles. The needle samples were collected from five sampling points in an area situated in the Southern Finland in the vicinity of a metal scrab plant. Reference needles were collected in the Central Finland. Needles originated from years 1991, 1992 and 1993.
Tetra- and pentachlorodibenzothiophenes are formed in waste combustion
1991
Abstract Two different waste combustion samples have been analyzed for tetra- and pentachlorodibenzothiophenes. HRGC/HRMS with a resolution of 20 000 was used for identification. By resolution of 10 000 chlorinated dibenzo-p-dioxins and some unknown compounds gave GC/SIM peaks at the exact masses of the chlorinated dibenzothiophenes. These peaks were no more present by resolution 20 000. Several tetra- and pentachlorodibenzothiophenes were found in both samples. In the other one of the samples the concentrations were seemingly high although exact quantitative determination could not be done.