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A 30 year old man was found with no signs of life in front of the house. The cyanide concentration in blood and urine was determined five years after the man's death. What is more, a stability study was conducted for 730 days in an authentic casework blood sample. Sample preparation procedure included precipitation with methanol:water mixture, solid phase extraction (SPE) and derivatization with the use of PFB-Br (pentafluorobenzyl bromide). The sample was analyzed using GC-QqQ-MS/MS (gas chromatopraphy coupled with tandem mass spectrometry) isotope dilution method. Separation was done using a SH-RXI-5MS column (30 m x 0.25 mm, 0.25 µm). Detection of PFB-CN and PFB-13CN was achieved using a triple-quadrupole mass spectrometer with an electron ionization (EI) ion source in multiple reaction monitoring (MRM) mode. After 5 years from the man's death, cyanide concentration was: 1900 ng/mL in blood and 500 ng/mL in urine. Stability study performed in an authentic blood sample 6 and 7 years after the man's death revealed cyanide concentrations of 1898.2 ng/mL and 1618.7 ng/mL, respectively. While spectrophotometric and colorimetric methods recorded both decrease and increase in cyanide concentration over time, newer chromatographic methods mainly indicate a decrease. The studies presented in this paper seem to confirm this trend. However, in order to interpretate the results of cyanide concentration in biological material reliably, more research is still necessary. [ABSTRACT FROM AUTHOR]

This report presents the application of ultra-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry with positive electrospray ionization, to determine ramipril in human plasma. First, the proteins in human plasma were precipitated using acetonitrile, then the supernatant was extracted by ethyl acetate at pH 3 and finally, the extract was analyzed using a UPLC-QTOF- MS system. The method was validated and the coefficient of determination (R2) was > 0.999, the lower limit of quantification (LLOQ) was 0.5 ng mL-1. Precision, recovery and stability were determined for three different concentrations of ramipril. RSD for this method ranged from 3.3 to 8.6 %. The intra-day mean recovery was from 65.3 to 97.3 %. In addition, the fragmentation of ramipril was studied. Due to high resolution of the spectrometer, it was possible to measure fragment masses accurately and determine their molecular and chemical formulas with high accuracy.

Synthetic cathinones comprise a large amount of substances present on the dark market, which creates an undeniably worldwide problem and still is posing a threat. A 22‐year‐old man was brought to the Emergency Room from a party, where he had ingested orally 20 g of mephedrone. The man exhibited a disorder of consciousness with no logical verbal contact and dilated pupils. Moreover, a metabolic acidosis was present. The patient died after an hour from an admission to the ER. Blood and vitreous humor collected during an autopsy were analyzed with the use of an ultra‐high‐performance liquid chromatography‐tandem mass spectrometry (UHPLC‐QqQ‐MS/MS) with the use of C18 column in multiple reaction monitoring (MRM) mode. Both biological specimens were prepared using liquid–liquid extraction (LLE) with the use of ethyl acetate and 0.5 M ammonium carbonate water solution (pH 9). The limit of quantification (LOQ) of the method was 0.5 ng/ml in both matrices; precision and accuracy values did not exceed ±15%. Recovery of the method was in the range of 86.1%–102.7%. Determined concentrations of 4‐CMC were 8542 and 9874 ng/ml in blood and vitreous humor, respectively. Other substances present in both biological materials were: atropine, diazepam, lidocaine, and its metabolite norlidocaine, as well as methcathinone and ethyl alcohol. The concentration presented in here described case is the highest ever reported 4‐CMC concentration. Important aspect is also receiving other NPS by recreational users than intended, which lead to accidental poisoning (in presented case user assumed 4‐CMC was 4‐MMC). [ABSTRACT FROM AUTHOR]

Widespread access to the Internet has an increasing influence on how suicides are committed. On websites such as eBay® or Amazon.com®, highly toxic substances including cyanides are available for purchase. In the last 5 years, a few fatal intoxications associated with Internet shopping and buying "suicide kits" have been reported. The epidemiology of intoxications reported by the American Association of Poison Control Centers between 2000 and 2018 shows that about 10% of all exposures to cyanide were related to suicide attempts and intentional ingestion of this substance. In order to determine the cyanide concentration in four fatal intoxication cases associated with Internet shopping, a headspace gas chromatography with dual-column/dual-flame ionization detection method was validated and applied to casework. The method was linear in range, from 1 to 50 mg/L, with a coefficient of determination of 0.999 (R2). The limit of quantification was 1.0 mg/L; the detection limit was 0.5 mg/L. Intra- and interday validation precision and accuracy did not exceed 10% and 15%, respectively. Recovery and matrix effect values ranged from 94.8% to 103.8% and from −5.2% to 3.8%, respectively. The cyanide concentrations were determined in biological fluids (blood, urine, bile, vitreous humor and gastric content) and postmortem tissue samples (spleen, kidney, liver and brain). The headspace gas chromatographic method, which is routinely used in clinical and forensic toxicology to quantify ethanol with its congeners (methanol, acetone, isopropanol, n -propanol and n -butanol), can also be applied to determine the cyanide concentrations in intoxication cases. The global problem of a high number of suicides each year requires increasing and more restrictive control of highly toxic substances available online as well as careful monitoring of human exposure to cyanide. This old and well-known poison is being increasingly used nowadays for suicidal purposes; therefore, the determination of cyanide in biological samples is still important in terms of clinical and forensic toxicology. [ABSTRACT FROM AUTHOR]