MALDI-Q-TOF mass spectrometric determination of gold and platinum in tissues using their diethyldithiocarbamate chelate complexes.

A rapid determination method is presented for gold (Au(3+)) and platinum (Pt(4+)) in tissues using matrix-assisted laser desorption ionization quadrupole time-of-flight mass spectrometry (MALDI-Q-TOF-MS). Au and Pt ions in wet-ashed tissue solution were reacted with diethyldithiocarbamate (DDC), and the resulting chelate complex ions Au(DDC)2 (+) and Pt(DDC)3 (+) were detected by MALDI-Q-TOF-MS using α-cyano-4-hydroxycinnamic acid as a matrix. The limit of detection (LOD) was 0.8 ng/g tissue and the quantification range was 2-400 ng/g for Au, and the LOD was 6 ng/g tissue and the quantification range was 20-4,000 ng/g for Pt. The Pt levels detected by MALDI-Q-TOF-MS in several tissues of a patient overdosed with cisplatin were nearly the same as those detected by flow-injection electrospray ionization mass spectrometry. The LODs of Au and Pt were 0.04 pg per well (sample spot) and 0.3 pg per well, respectively. To our knowledge, this is the first attempt to quantify Au(3+) and Pt(4+) ions in tissues by MALDI-Q-TOF-MS.

Detection and quantification of etomidate and metomidate in human hairs by ultraperformance liquid chromatography with triple quadrupole mass spectrometry (UPLC-MS/MS).

PURPOSE: Intravenous narcotic agents, such as etomidate and metomidate, has been widely spread and abused in the world, including in Korea and China; thus, it is important to establish validated and sensitive analytical method for these compounds. Human hair as a biological sample has various advantages, including a wide detection window of drugs, compared to other typical samples, such as urine and blood in investigation. The purpose of this communication is to develop a reliable and useful method for the simultaneous detection and quantification of etomidate and metomidate in human hair samples by ultraperformance liquid chromatography combined with triple quadrupole mass spectrometry (UPLC-MS/MS), and to apply it for authentic samples in abuse cases. METHODS: The hair samples were washed with a detergent solution, followed by with water and acetone. After drying, they were cut into approximately 2 mm sections and then ground to powder by a low-temperature grinder. The 20 mg of hair powder plus internal standard in 1 mL of methanol was vortexed and then centrifuged to obtain the supernatant layer, followed by subjecting to analysis. RESULTS: The coefficient of determination (r2) values of the calibration curves of etomidate and metomidate in the hair samples were both more than 0.99 in the range of 1-500 ng/mg and 1-500 pg/mg, respectively. The limits of detection and lower limits of quantification were 0.5 and 1 pg/mg, respectively, for the both target compounds. Other tested validation data were all satisfactory. Etomidate and metomidate could be detected in the all hair samples and cigarette oil, which were seized by the police. The concentrations of etomidate and metomidate obtained from 10 samples from suspects were 5.48-45.7 ng/mg and 3.60-377 pg/mg, respectively. The concentrations of etomidate and metomidate in the cigarette oil were 95.8 µg/mg and 2.8 µg/mg, respectively. CONCLUSIONS: In this study, a simple and reliable analytical method for etomidate and metomidate in the human hair has been established. To the best of our knowledge, this is the first report to establish a method for the simultaneous detection and quantification of etomidate and metomidate in the human hair, and to apply it to authentic samples seized in authentic cases.

Detection of new metabolites of risperidone in the solid tissues and body fluids obtained from two cadavers by high resolution tandem mass spectrometry.

Risperidone (Ris) is a second-generation antipsychotic that belongs to the chemical class of benzisoxazole derivatives. 9-Hydroxy (9OH-) Ris is well known among the six reported metabolites of Ris and had been examined using not only blood but also other matrices, but the other five metabolites reported such as benzisoxazole ring-cleaved Ris (c-Ris) and c-9OH-Ris had been detected only in blood, urine and feces. In the present work, large peaks of c-Ris and c-9OH-Ris were detected in the liver, kidney, cerebrum, blood, pericardial fluid, bile and urine obtained from two cadavers. There is a potential that c-Ris and c-9OH-Ris will be good markers to prove Ris consumption in forensic toxicology cases. For example, the peak ratios of c-Ris against the parent Ris in the kidney and blood were as high as 3.9 and 3.6 in cadaver 1; and 7.0 and 7.9 in cadaver 2, respectively. In addition to the previously reported six metabolites, five new metabolites such as dehydrogenated-Ris, 7-keto-Ris and three benzisoxazole ring-cleaved metabolites were disclosed in the present work, and the pathways for the totally eleven metabolites detected in human solid tissues and body fluids have also been proposed, because such pathways were neither reported nor discussed previously.

Simple quantification of propofol and its metabolites in blood and urine using gas chromatography-tandem mass spectrometry (GC-MS/MS).

An analytical method which was used for the simultaneous detection and quantification of propofol and its metabolites in human blood and urine by gas chromatography-tandem mass spectrometry (GC-MS/MS) was newly established and applied to authentic human samples obtained from the deceased. The QuEChERS method was employed, and then analyzed by GC-MS/MS. We separately used sulfatase and ß-glucuronidase to hydrolyze the urine sample and calculated the increase of propofol and 4-hydroxypropofol before and after the hydrolysis. The results of urinary concentrations in urine from the subject were: 4.88 µg/mL for propofol, 0.53 µg/mL for 4-hydroxypropofol, 3.35 µg/mL for propofol-glucuronide, 0.31 µg/mL for the total concentration of 1-(2,6-diisopropyl-1,4-quinol)-glucuronide plus 4-(2,6-diisopropyl-1,4-quinol)-glucuronide, and 0.39 µg/mL for 4-(2,6- diisopropyl-1,4-quinol)-sulfate. The lower limit of quantification was 10 ng/mL for all determined compounds; the extraction recoveries were not less than 57.2 %. Intraday and interday precisions and accuracies were all less than 10 %. The calibration curves for propofol and 4-hydroxypropofol in human urine showed the correlation values of not less than 0.999; propofol and 4-hydroxypropofol in blood also presented good linearities in the concentration ranges of 0.1-10 µg/mL. The two compounds had good stability within 7 days at 25, 4, and -20 ℃. To our knowledge, this is the first trial to establish a simple and reliable method to simultaneously detect and quantify of propofol and its phase I and II metabolites in human blood and urine samples by GC-MS/MS.

Quantification of the benzimidazole opioid analog isotonitazene in human hair using liquid chromatography-tandem mass spectrometry.

Benzimidazole opioids were originally developed from the late 1950s to 1970s as analgesics for medical use, although a lot of them could not be approved as licit medicines because of their severe side effects and physical dependence. Such benzimidazole opioid analogs as abused drug, however, have recently been found in illicit drug markets throughout the world. Isotonitazene is one such benzimidazole opioids, whose analgesic potency can be as much as 500 times greater than that of morphine, according to previous animal studies. In line with this potency, a couple of hundred fatalities related to it were reported to date. In this study, a well validated method for the quantification of isotonitazene in human hair samples using liquid chromatography (LC)-tandem mass spectrometry (MS/MS) was established, and could be applied to authentic samples which were seized by the police security bureau. Isotonitazene concentrations in the seized hair averaged 6.11 pg/mg. The LLOQ and LOD of this method were 1.25 and 2.5 pg/mg, respectively; the calibration curve of the substance in hair samples showed a good linearity in the concentration range of 2.5-250 pg/mg (r > 0.999); the extraction recovery rates were 87.3-105% in the tested range; the inter- and intra-day precisions and accuracies (%biases) were not greater than 9.09% for each determination. Isotonitazene in human hair showed good stability at room temperature and under dark storage conditions for 30 days. As for matrix effect in hair samples, moderate ion suppression of target substances could be found. This is the first report for the analysis of isotonitazene in human hair samples.

Quantification of nimetazepam and its metabolite in human hair samples using liquid chromatography-tandem mass spectrometry: Case report.

Nimetazepam (marketed brand names; Erimin and Lavol) is an intermediate acting benzodiazepine derivative, which was widely used mainly in East and Southeast Asian region countries including Japan, Malaysia, Brunei, the Philippines, Thailand, Indonesia, Hong Kong, Singapore and China. Nimetazepam and its metabolite 7-aminonimetazepam were quantified from human hair samples by liquid chromatography tandem-mass spectrometry (LC-MS/MS), under selective reaction monitoring mode. Using diazepam-d5 as an internal standard, the concentration of nimetazepam and its metabolite 7-aminonimetazepam could be determined by matrix matched calibration method. Extraction of the target compounds was performed by using methanol, followed by evaporation and being concentrated with nitrogen. The Limit of quantification concentrations of nimetazepam and its metabolite 7-aminonimetazepam in hair samples were both 25 pg/mg by established method. The concentrations of nimetazepam in hair samples obtained from 2 users were 27.4, and 22.0 pg/mg, respectively; the concentrations of 7-animonimetazepam in hair samples were 54.2 and 29.1 pg/mg, respectively. In our study, the 7-aminonimetazepam concentrations in hair was higher than those of nimetazepam in the authentic hair samples. To our knowledge, this is the first report to establish the detailed procedure for quantificating nimetazepam and 7-aminonimetazepam in human hair by LC-MS/MS.

Quantification of a new recreational drug 2-methoxyqualone in human hair using gas chromatography-tandem mass spectrometry.

A method for identification and quantification of 2-methoxyqualone, an newly emerging quinazolinone derivative recreational drug, in human scalp hair was established using gas chromatography (GC)-tandem mass spectrometry (MS/MS). In this report, authentic cases are presented, in which the suspects were seized by police security bureau; the police in China requested our laboratory to identify and quantify the involved drug(s) of abuse in the hair samples of the suspects. After washing and cryo-grinding the authentic hair samples, the target compound was extracted with methanol, and the solvent layer was evaporated to dryness. The residue was reconstituted in methanol and analyzed by GC-MS/MS. 2-Methoxyqualone concentrations in the hair were between 35.1 and 116 pg/mg. The calibration curve of the substance in hair samples showed a good linearity in the concentration range of 10-1000 pg/mg (r > 0.998); the extraction recovery rate, 88.8-105.6 %; the interday and intraday precisions and accuracies (biases), not greater than 8.9 %. 2-Methoxyqualone in human hair had good stability under three different storage conditions at room (20 °C), refrigerated (4 °C) and frozen (- 20 °C) temperatures for at least 7 days. In the present report, simple and rapid quantification method for 2-methoxyqualone in human scalp hair have been established using GC-MS/MS and it could successfully be applied to authentic forensic toxicological cases. To our knowledge, this is the first report for quantification of 2-methoxyqualone in human hair samples.

Quantification of olanzapine and its three metabolites by liquid chromatography-tandem mass spectrometry in human body fluids obtained from four deceased, and confirmation of the reduction from olanzapine N-oxide to olanzapine in whole blood in vitro.

PURPOSE: Quantification of olanzapine (OLZ) and its metabolites such as N-desmethylolanzapine (DM-O), 2-hydroxymethylolanzapine (2H-O) and olanzapine N-oxide (NO-O) in five kinds of human body fluids including whole blood by liquid chromatography (LC)-tandem mass spectrometry (MS/MS) has been presented; the quantification methods were carefully devised and validated using the matrix-matched calibration and standard addition methods. METHODS: OLZ and its three metabolites were extracted from 40 µL each of body fluids by two-step liquid-liquid separations. The samples and reagents were pre-cooled in a container filled with ice for the extraction because of the thermal instability of OLZ and its three metabolites especially in whole blood. RESULTS: The limits of quantification (LOQs) of OLZ and 2H-O were 0.05 ng/mL and those of DM-O and NO-O were 0.15 ng/mL in whole blood and urine, respectively. The concentrations of OLZ and its metabolites in heart whole blood, pericardial fluid, stomach contents, bile and urine were determined for two cadavers and those in whole blood and urine for the other two cadavers. The reduction from NO-O to OLZ was observed at 25 â„ƒ in whole blood in vitro. CONCLUSIONS: To our knowledge, this is the first report on the quantification of metabolites of olanzapine in the authentic human body fluids by LC-MS/MS as well as on the confirmation of in vitro reduction from NO-O to OLZ in whole blood that seems to have induced the quick decrease of NO-O.

Quantification of risperidone and paliperidone by liquid chromatography-tandem mass spectrometry in biological fluids and solid tissues obtained from two deceased using the standard addition method.

Risperidone (RIS) is an atypical antipsychotic agent and its 9-hydroxylated metabolite named paliperidone (PAL) also has pharmacological properties similar to that of RIS. Quantifications of RIS and PAL in authentic human biological fluids and solid tissues by liquid chromatography (LC)-tandem mass spectrometry (MS/MS) have not been reported yet although those in plasma (and blood) were reported abundantly. In the present work, a quantification method for RIS and PAL based on the standard addition method was devised and validated for the human fluid and solid tissue specimens. RIS and PAL in biological fluids were quantified only after their dilution and deproteinization. The concentrations of RIS and PAL in the heart whole blood, pericardial fluid, stomach contents, bile, urine, liver, kidney and cerebrum were determined for a deceased who had been treated with RIS therapeutically, and also a deceased who had ingested RIS with other drugs intentionally. To our knowledge, this is the first report on the quantification of RIS and PAL by LC-MS/MS in the authentic human tissues and biological fluids.

The next addiction-causing drug class 4-quinazolinone derivatives: analyses of methaqualone analogs including recently discovered 2-methoxyqualone by different modes of mass spectrometry.

PURPOSE: The information on analytical methods for 4-quinazolinone recreational drugs, such as methaqualone, etaqualone and 2-methoxyqualone, is almost scant. In this study, product ion spectra of gas chromatography-tandem mass spectrometry (GC-MS/MS) with different collision energies were presented for these drugs. Because 2-methoxyqualone is a new recreational drug discovered in dubious tablets very recently, much more detailed data obtained by different types of mass spectrometry instruments, and quantification data of 2-methoxyqualone in the tablet together with its validation were demonstrated. METHODS: The methods for analyses were GC-MS/MS, high-resolution ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry and liquid chromatography-tandem mass spectrometry. RESULTS: The GC-MS/MS product ion spectra of the three compounds with different collision energies have not been reported before. They were very useful to tentatively identify unknown compounds. If a reference standard is available, the final identification and quantification can be achieved by measurements of product ion spectra and in selected reaction monitoring mode very easily by GC-MS/MS. The final identification and quantification for the new 2-methoxyqualone were performed in this way. The content of the compound was 69.8 ± 0.5% (w/w) in the tablet. Acetaminophen and caffeine coexisted in the tablet with approximate concentrations at 10 and 5%, respectively. CONCLUSIONS: In this article, we have presented product ion spectra of methaqualone, etaqualone and 2-methoxyqualone at different collision energies by GC-MS/MS for the first time. In addition, this is the first paper to describe the details of quantification of 2-methoxyqualone in the authentic seized product.

Determination of azide in gastric fluid and urine by flow-injection electrospray ionization tandem mass spectrometry.

A rapid method was developed to identify and quantify the azide ion (N(3)(-)) in gastric fluid and urine. N(3)(-) in diluted biological fluids was reacted with NaAuCl(4) to produce Au(N(3))(2)(-), which was extracted with octanol. Five microliters of the extract were flow-injected into an electrospray ionization tandem mass spectrometric instrument. Quantification of N(3)(-) was performed by selected reaction monitoring of the product ion Au(N)(N(3))(-) at m/z 253, which was derived from the precursor ion Au(N(3))(2)(-) at m/z 281, using 50 µL of aqueous solution within 10 min. This method was found to be linear up to 10(-5) M, to have a limit of quantification of 10(-7) M, a limit of detection of 3.0 × 10(-8) M, and a coefficient of variation of ≦10% at 10(-7) M. In the case of urine, 50 µL of urine were spiked with N(3)(-), this was diluted 10-fold and passed through 1 mL of a resin, and finally diluted to 100-fold of the original. This method was linear up to 10(-3) M, had a limit of quantification of 10(-5) M, a limit of detection of 3.0 × 10(-6) M, and coefficient of variation of ≦8.8% for an original urine concentration of 10(-5) M. The practical applicability of this method was checked by diluting 1 µL of a suspected suicide victim's gastric fluid 20,000-fold and 1 µL of the victim's urine 5,000-fold and then measuring the N(3)(-) levels. These levels were found to be (7.5 ± 1.0) × 10(-2) M and (3.2 ± 0.4) × 10(-3) M, respectively.

Non-fentanyl-derived synthetic opioids emerging during recent years.

Purpose: Since the appearance of fentanyl followed by its many kinds of analogues around 1988, North America has been exposed to fierce synthetic opioid pandemic resulting in more than 130,000 deaths due to their overdoses until May 2019, when China declared to prohibit the licit fentanyl analog production. However, the Chinese announcement did not go into force in USA due to the adroit strategies of tough traffickers. Thus, contrary to the expectation, the number of synthetic opioid products and their poisoning cases in USA has increased by about 30%; especially, various benzimidazole synthetic opioids have revived on the illicit drug market during a recent few years. In this article, the recent abrupt changes in the situations of illicit synthetic opioid market and their current abuses are described. Methods: Various databases, such as SciFinder, Google, and Google Scholar, were utilized to collect relevant reports referring old but newly appearing synthetic opioids. Results: At the present time, there are several families of new synthetic opioids, which are not fentanyl derivatives; MT-45 and its analogs, benzamide and 2-phenylacetamide opioids (U-series opioids), and benzimidazole opioids. Most of the above substances had been developed in 1950s to 1970s, but had never been used as analgesic medicines, because of their severe adverse effects, such as respiratory depression, physical dependence, and resulting deaths. However, there is possibility that these drugs will become main illicit synthetic opioids in place of the fentanyl analogs during coming several years from this time. Conclusions: All of the above non-fentanyl-derived families had been developed 50-70 years ago to establish them as analgesic medicines, but had been unsuccessful. These drugs largely appeared in the illicit drug markets in North America, Europe, and Australia, during recent years. Pharmacological, toxicological, and metabolic studies are insufficient for benzamide and 2-phenylacetamide opioids, and are very scant especially for benzimidazole opioids. This time we should start studying pharmacotoxicology of the newly emerging synthetic opioids to alert forensic toxicologists in the world and to suppress their rapid and wide spread in the world. Supplementary Information: The online version contains supplementary material available at 10.1007/s11419-022-00624-y.

Non-fentanyl-derived synthetic opioids emerging during recent years.

PURPOSE: Since the appearance of fentanyl followed by its many kinds of analogues around 1988, North America has been exposed to fierce synthetic opioid pandemic resulting in more than 130,000 deaths due to their overdoses until May 2019, when China declared to prohibit the licit fentanyl analog production. However, the Chinese announcement did not go into force in USA due to the adroit strategies of tough traffickers. Thus, contrary to the expectation, the number of synthetic opioid products and their poisoning cases in USA has increased by about 30%; especially, various benzimidazole synthetic opioids have revived on the illicit drug market during a recent few years. In this article, the recent abrupt changes in the situations of illicit synthetic opioid market and their current abuses are described. METHODS: Various databases, such as SciFinder, Google, and Google Scholar, were utilized to collect relevant reports referring old but newly appearing synthetic opioids. RESULTS: At the present time, there are several families of new synthetic opioids, which are not fentanyl derivatives; MT-45 and its analogs, benzamide and 2-phenylacetamide opioids (U-series opioids), and benzimidazole opioids. Most of the above substances had been developed in 1950s to 1970s, but had never been used as analgesic medicines, because of their severe adverse effects, such as respiratory depression, physical dependence, and resulting deaths. However, there is possibility that these drugs will become main illicit synthetic opioids in place of the fentanyl analogs during coming several years from this time. CONCLUSIONS: All of the above non-fentanyl-derived families had been developed 50-70 years ago to establish them as analgesic medicines, but had been unsuccessful. These drugs largely appeared in the illicit drug markets in North America, Europe, and Australia, during recent years. Pharmacological, toxicological, and metabolic studies are insufficient for benzamide and 2-phenylacetamide opioids, and are very scant especially for benzimidazole opioids. This time we should start studying pharmacotoxicology of the newly emerging synthetic opioids to alert forensic toxicologists in the world and to suppress their rapid and wide spread in the world.

Quantitation of sibutramine in human hair using gas chromatography-isotope dilution tandem mass spectrometry.

PURPOSE: An analytical method for quantitation of sibutramine in human hair using gas chromatography (GC)-isotope dilution tandem mass spectrometry (MS/MS) was newly established. In this article, a case is presented, in which a 3.5-year-old male child accidentally ingested chocolate-like product containing sibutramine, showing various symptoms; he could survived the crisis. About 1 month after the incident, his scalp hair sample was subjected to analysis for the causative sibutramine. METHOD: After cryo-grinding for the hair sample, target compound was extracted with methanol, and the solvent layer was evaporated to dryness. The residue was reconstituted in methanol and analyzed by GC-MS/MS, using the selected reaction monitoring (SRM) mode with a deuterated isotope internal standard. RESULTS: The substance was identified as sibutramine; its concentration in the hair sample of the child was 58.6 pg/mg. The calibration curve of sibutramine in hair samples had a good linear relationship in the concentration range of 20-200 pg/mg (r > 0.99); the extraction recovery rate 85.2-91.8%; the interday and intraday precision and accuracy (bias) examined not greater than 9.6%. Sibutramine in human hair had good stability under 3 different storage conditions at room (20 °C), refrigerated (4 °C) and frozen ( - 20 °C) temperatures for at least 7 days. CONCLUSIONS: It should be expected that the method established in this study would contribute to rapid determinations of sibutramine. To our knowledge, this is the first report describing quantitation of sibutramine in an authentic human hair sample by GC-MS/MS.

Quantification of MDMB-4en-PINACA and ADB-BUTINACA in human hair by gas chromatography-tandem mass spectrometry.

PURPOSE: To test synthetic cannabinoid (SCs) in parent forms from living human, the hairs seems to be one of the best samples, because of the non-invasiveness upon their collection. The purpose of this study is to establish a method for quantification of MDMB-4en-PINACA and ADB-BUTINACA, the most recently abused SCs in hair samples, using gas chromatography-tandem mass spectrometry (GC-MS/MS). METHODS: The collected hair samples were washed with a detergent solution, following by water and acetone. After drying cutting them into about 2 mm sections, they were ground by a cryogenic grinder into powder. The 50-mg powder with internal standard(s) plus 1 mL methanol were vortexed, and centrifuged to obtain the supernatant layer. After its evaporation and reconstitution with 50 µL methanol, 1-µL aliquot of it was subjected to analysis. RESULTS: The standard calibration curves were created for both MDMB-4en-PINACA and ADB-BUTINACA in blank hair samples; good linear curves were obtained in the range of 20-20,000 pg/mg with correlation coefficients greater than 0.99. The limits of detection and limits of quantification were 10 and 20 pg/mg, respectively. Other validation parameters were all satisfactory. The concentrations of MDMB-4en-PINACA obtained from 3 authentic subjects and ADB-BUTINACA obtained from 3 authentic subjects were 26.2-806 pg/mg and 63.1-430 pg/mg, respectively. CONCLUSIONS: In the present article, the details of simple and rapid quantification of MDMB-4en-PINACA and ADB-BUTINACA in human scalp hair have been established. To our knowledge, this is the first report for quantification of SCs in hair samples by GC-MS/MS.

A fatal case involved in pyrethroid insecticide ingestion: quantification of tetramethrin and resmethrin in body fluids of a deceased by LC-MS/MS.

PURPOSE: The quantification of parent molecules of pyrethroids tetramethrin and resmethrin in human specimens by a mass spectrometry (MS) technique has not been reported yet. A woman in her 60s was found dead in a wasteland. At the scene, an empty beer can and a spray for insecticides containing tetramethrin and resmethrin were found. Therefore, the concentrations of tetramethrin and resmethrin in postmortem specimens and the methanol solution used for rinsing the inside of the beer can were determined using liquid chromatography (LC)-tandem mass spectrometry (MS/MS). METHODS: The quantification method by LC-MS/MS for intact parent molecules of tetramethrin and resmethrin in whole blood and urine has been devised and validated in this work. The method was applied to the quantification of tetramethrin and resmethrin in whole blood, urine and stomach contents obtained from a cadaver at autopsy. RESULTS: The limits of detection of tetramethrin and resmethrin were 0.06 and 0.03 ng/mL; limits of quantification were 0.2 and 0.1 ng/mL in blood and urine, respectively. The concentrations of tetramethrin of the deceased were 11.1 ± 1.2 and 0.425 ± 0.017 ng/mL for stomach contents and urine, respectively; the concentration of resmethrin in stomach contents was 1.77 ± 0.18 ng/mL. The tetramethrin and resmethrin were unstable in blood and urine at room temperature; they should be kept at not higher than 4 â„ƒ. CONCLUSIONS: To our knowledge, this is the first report for quantification of unchanged tetramethrin and resmethrin in human specimens obtained in a fatal case.

Long-term stability of 24 synthetic cannabinoid metabolites spiked into whole blood and urine for up to 168 days, and the comparable study for the 6 metabolites in non-spiked real case specimens stored for 1-5 years.

PURPOSE: The aim of this study is to investigate the stabilities of the 24 synthetic cannabinoid metabolites (SCMs) in blood and urine at various temperatures from - 30 to 37 ℃ stored for 1-168 days. In addition, experiments of stabilities at lower temperatures and for much longer duration have been performed as described below. METHODS: The quantification was performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The blank blood and urine spiked with SCMs and non-spiked real case (authentic) specimens were incubated at 37 ℃ up to 56 days and at 22, 4 or - 30 ℃ up to 168 days. The non-spiked authentic blood and urine specimens were also stored at - 30 or - 80 ℃ for 1, 3 or 5 years to investigate stabilities during very long time frames. RESULTS: All the 24 SCMs were much more stable in urine than in blood at 37, 22 or 4 ℃. All 24 SCMs spiked into blood or urine were stable at - 30 ℃ for up to 168 days. The 6 SCMs in the authentic specimens exhibited long stabilities at - 30 or - 80 ℃ for 3-5 years. Some tendencies were observed according to the relation between the structures of SCMs and their stabilities. CONCLUSIONS: The long-term stabilities of 24 SCMs in spiked samples and those of 6 SCMs in the authentic specimens were examined using LC-MS/MS. SCMs were largely very stable and usable several years after storage at - 30 or - 80 ℃.

GC/MS with post-column switching for large volume injection of headspace samples: sensitive determination of volatile organic compounds in human whole blood and urine.

When volatile or semivolatile compounds are measured by headspace (HS) gas chromatography (GC)/mass spectrometry (MS), the maximum gas volume to be injected is usually 0.5-1.0 mL; over the volume, the MS detector automatically shuts down due to impairment of the vacuum rate of the MS ionization chamber. To overcome the problem, we modified the gas flow routes of a new type of GC/MS instrument to create a postcolumn switching system, which can eliminate the large volume of gas before introduction of target compounds into the MS ionization chamber. Our HS-GC/MS system enabled injection of as large as 5 mL of HS gas without any disturbance. As the first example analysis, we tried to establish the analysis of naphthalene and p-dichlorobenzene in human whole blood and urine by this method with large volume injection. The limits of detection for both compounds in whole blood and urine were as low as about 10 and 5 pg/mL, respectively. The validation data and actual measurements were also demonstrated. The new GC/MS system has great potential to analyze any type of volatile or semivolatile organic compounds in biological matrixes with very high sensitivity and full automation.

Determination of cyanide in blood by electrospray ionization tandem mass spectrometry after direct injection of dicyanogold.

An electrospray ionization tandem mass spectrometric (ESI-MS-MS) method has been developed for the determination of cyanide (CN(-)) in blood. Five microliters of blood was hemolyzed with 50 µL of water, then 5 µL of 1 M tetramethylammonium hydroxide solution was added to raise the pH of the hemolysate and to liberate CN(-) from methemoglobin. CN(-) was then reacted with NaAuCl(4) to produce dicyanogold, Au(CN)(2)(-), that was extracted with 75 µL of methyl isobutyl ketone. Ten microliters of the extract was injected directly into an ESI-MS-MS instrument and quantification of CN(-) was performed by selected reaction monitoring of the product ion CN(-) at m/z 26, derived from the precursor ion Au(CN)(2)(-) at m/z 249. CN(-) could be measured in the quantification range of 2.60 to 260 µg/L with the limit of detection at 0.56 µg/L in blood. This method was applied to the analysis of clinical samples and the concentrations of CN(-) in the blood were as follows: 7.13 ± 2.41 µg/L for six healthy non-smokers, 3.08 ± 1.12 µg/L for six CO gas victims, 730 ± 867 µg for 21 house fire victims, and 3,030 ± 97 µg/L for a victim who ingested NaCN. The increase of CN(-) in the blood of a victim who ingested NaN(3) was confirmed using MS-MS for the first time, and the concentrations of CN(-) in the blood, gastric content and urine were 78.5 ± 5.5, 11.8 ± 0.5, and 11.4 ± 0.8 µg/L, respectively.

In Vivo Metabolites of AB-PINACA in Solid Tissues Obtained from Its Abuser: Comparison with In Vitro Experiment.

In this study, solid tissues such as the lung, liver, kidney and urine were highlighted to profile the AB-PINACA in vivo metabolites in a fatal abuse case, although such metabolite analysis is usually made with urine specimens. We compared the relative peak intensities of in vivo metabolites of AB-PINACA in lung, liver, kidney and urine specimens collected at the autopsy of its abuser with its in vitro metabolites in human hepatocytes. The metabolites of AB-PINACA in tissues were extracted after homogenization. The urine specimen and portions of the extracted metabolites from tissues were firstly hydrolyzed with ß-glucuronidase, and the metabolites were extracted. For in vitro experiment, AB-PINACA was incubated with human hepatocytes for 3 h to produce its metabolites. The identification of the in vivo and in vitro metabolites was performed using liquid chromatography (LC)-high-resolution Orbitrap-tandem mass spectrometry (MS-MS), and the relative intensities of these metabolites were measured using low resolution LC-quadrupole-ion trap-MS-MS. Thirteen metabolites of AB-PINACA were characterized in vivo in several human specimens and in in vitro human hepatocytes. They were produced by the terminal amide hydrolysis to carboxylic acid, hydroxylation, carbonyl formation and/or glucuronidation. The most detectable metabolite in the hepatocytes, lung or liver was the one produced by the terminal amide hydrolysis, whereas the top metabolite in the kidney or urine was the one produced by hydroxylation or carbonyl formation on the pentyl side chain after the terminal amide hydrolysis, respectively. At least 12 metabolites of AB-PINACA were detected in authentic human lung, liver or kidney specimen from a cadaver. It is concluded that the postmortem metabolite profiling of AB-PINACA can be fulfilled with solid tissues, and the lung and kidney were most recommendable especially when urine specimen is not available.