Search results for "Forensic toxicology"
showing 10 items of 26 documents
Determination of ethyl sulfate – a marker for recent ethanol consumption – in human urine by CE with indirect UV detection
2006
A CE method for the determination of the ethanol consumption marker ethyl sulfate (EtS) in human urine was developed. Analysis was performed in negative polarity mode with a background electrolyte composed of 15 mM maleic acid, 1 mM phthalic acid, and 0.05 mM cetyltrimethylammonium bromide (CTAB) at pH 2.5 and indirect UV detection at 220 nm (300 nm reference wavelength). This buffer system provided selective separation conditions for EtS and vinylsulfonic acid, employed as internal standard, from urine matrix components. Sample pretreatment of urine was minimized to a 1:5 dilution with water. The optimized CE method was validated in the range of 5-700 mg/L using seven lots of urine. Intra-…
Detection of gamma-hydroxybutyrate in hair: Validation of GC–MS and LC–MS/MS methods and application to a real case
2012
A gas chromatography-mass spectrometry (GC-MS) and a liquid chromatography tandem mass spectrometry (LC-MS/MS) method were validated for quantifying endogenous and exogenous hair concentrations of gamma-hydroxybutyrate (GHB). The GC-MS method is based on overnight extraction of 25 mg hair in NaOH at 56 °C, liquid/liquid extraction in ethylacetate and trimethylsylil derivatization; analysis is by electron ionization and single ion monitoring of three ions. The LC-MS/MS method entails a rapid digestion of 25 mg hair with NaOH at 75 °C for 40 min, liquid/liquid extraction in ethylacetate and reconstitution of the extract in the LC mobile phase; negative ion electrospray ionization and multiple…
Case report: Another death associated to γ-hydroxybutyric acid intoxication
2019
Abstract We report a fatal γ-hydroxybutyric acid (GHB) intoxication of a forty-year old man. According to an acquaintances’ statement, the deceased had drunk a beverage containing GHB approximately five hours before he was found. Postmortem GHB concentrations were determined using gas chromatography coupled to single quadrupole mass spectrometry after simple protein precipitation with methanol and derivatization with BSTFA (1% TMCS). Concentrations in body fluids and tissues of the deceased were as follows: cardiac blood 384 mg/L, femoral blood 358 mg/L, urine 864 mg/L, brain tissue 211 mg/kg, liver tissue 201 mg/kg, kidney tissue 492 mg/kg, bile 334 mg/L and gastric content 2025 mg/L. In a…
GHB related acids (dihydroxy butyric acids, glycolic acid) can help in the interpretation of post mortem GHB results.
2020
Post mortem gamma hydroxy butyric acid (GHB) concentrations should be interpreted with caution since GHB concentrations can increase after death. Post mortem concentrations after the intake of GHB ante mortem do overlap with concentration ranges in cases without known exposure to GHB and make an interpretation challenging. GHB is known to undergo intensive metabolism to related acids (glycolic acid (GA), succinic acid (SA), 2,4- and 3,4-dihydroxy butyric acid (2,4-OH-BA and 3,4-OH-BA)). GHB and these related acids were analyzed using a validated gas chromatographic mass spectrometric (GC-MS) method after liquid liquid extraction and trimethylsilylation. SA concentrations were not usable pos…
In vitro production of GHB in blood and serum samples under various storage conditions
2011
Abstract The in vitro production of GHB was observed in freshly collected, untreated whole blood samples using glass BD-Vacutainers and polypropylene S-monovettes. GHB concentrations were determined daily over a period of one week and after 3, 6 and 9 weeks again. Furthermore, the GHB concentration in 40 untreated random whole blood samples stored at 4 °C for a longer period of time (10 samples 12 month, 10 samples 24 month and 20 samples 36 month) was also determined. For comparison, the in vitro production of GHB in freshly collected and prepared serum samples was observed. GHB serum concentrations were determined three times over a period of one week and once again after six weeks. Sampl…
A fatal paramethoxymethamphetamine intoxication.
2003
During the last years in Germany a marked increase in the use of amphetamines such as 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) has been observed. The use of these recreational drugs is especially common among young people participating in rave parties. Occasionally ring-methoxylated phenethylamine derivatives like paramethoxymethamphetamine (PMMA) or paramethoxyamphetamine (PMA) are found in street drugs offered as ecstasy. These compounds exhibit a higher toxicity than the methylenedioxyamphetamine derivatives. We report on the death of a 22-year-old man after the ingestion of ecstasy pills containing PMMA and PMA. The PMMA concentration in femoral blood was 0.85 mg/l. Besides PMA…
A preliminary study on the stability of benzodiazepines in blood and plasma stored at 4 degrees C.
1997
An approach to determine the stability of benzodiazepines and some of their metabolites (n = 13) by means of a routinely applied gas chromatographic method using electron capture detection was made in this preliminary study. Validation data of the method are given. Spiked blood and plasma samples were stored at 4 degrees C and analysed at selected times up to 240 days. The concentrations of all analytes had decreased to at least 60% of the original levels at the end of the observation period. A clear pattern of breakdown could not be established. The data obtained suggest that results from long-term stored samples should be interpreted cautiously. Further investigations concerning the stabi…
Detection of the synthetic drug 4-fluoroamphetamine (4-FA) in serum and urine.
2010
Abstract 4-Fluoroamphetamine (4-FA) was detected in the blood and urine of two individuals suspected for driving under the influence (DUI). The test for amphetamines in urine subjected to immunoassay screening using the CEDIA DAU assay proved positive. Further investigations revealed a 4-FA cross-reactivity of about 6% in the CEDIA amphetamine assay. 4-FA was qualitatively detected in a general unknown screening for drugs using GC/MS in full scan mode. No other drugs or fluorinated phenethylamines were detected. A validated GC/MS method was established in SIM mode for serum analysis of 4-FA with a limit of detection (LOD) of 1 ng/mL and a lower limit of quantification (LLOQ) of 5 ng/mL. Int…
Determination of the enantiomeric composition of amphetamine, methamphetamine and 3,4-methylendioxy-N-methylamphetamine (MDMA) in seized street drug …
2021
Amphetamine (speed), methamphetamine (crystal meth), and 3,4-methylenedioxy-N-methylamphetamine (MDMA, ecstasy) represent the most frequently abused amphetamine-type stimulants (ATS). Differences in pharmacological potency and metabolism have been shown for the enantiomers of all three stimulants. Legal consequences in cases of drug possession may also differ according to the German law depending on the enantiomeric composition of the seized drug. Therefore, enantioselective monitoring of seized specimens is crucial for legal and forensic casework. Various kinds of samples of amphetamine (n = 143), MDMA (n = 94), and methamphetamine (n = 528) that were seized in southern Germany in 2019 and…
Preliminary Practical Findings on Drug Monitoring by a Transcutaneous Collection Device
1996
A noninvasive and nonocclusive skin patch (Sudormed™) was investigated for the systematic collection of drugs of abuse over a period of several days. First, the applicability and user friendliness were tested by volunteers. The permeability of the polyurethane dressing from the outside to the inside for an aqueous solution was shown by incubating the outside layer with Rhodamine B. No fluorescence could be detected in the cotton pad beneath. A single dose experiment using theophylline as a model compound showed that there was a delay in time before the substance could be determined in the pad. The drug content decreased with increasing time of patch application. When eight volunteers partic…