41 results on '"Hideki Nozawa"'
Search Results
2. 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
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Kayoko Minakata, Koutaro Hasegawa, Hideki Nozawa, Itaru Yamagishi, Naotomo Miyoshi, Masako Suzuki, Takuya Kitamoto, Minako Kondo, Kanako Watanabe, and Osamu Suzuki
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Tandem Mass Spectrometry ,Cannabinoids ,Biochemistry (medical) ,Temperature ,Toxicology ,Chromatography, Liquid ,Body Fluids ,Pathology and Forensic Medicine - Abstract
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.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.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.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 ℃.
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- 2022
3. Investigation on toxicological usefulness of synovial fluids, as an alternative matrix: postmortem distribution/redistribution of triazolam and its predominant metabolite α-hydroxytriazolam in human body fluids
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Naotomo Miyoshi, Hideki Nozawa, Koutaro Hasegawa, Kayoko Minakata, Itaru Yamagishi, Amin Wurita, and Masako Suzuki
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Chromatography ,Triazolam ,Chemistry ,Metabolite ,Biochemistry (medical) ,Pharmacology toxicology ,Toxicology ,Body Fluids ,Pathology and Forensic Medicine ,Matrix (chemical analysis) ,Feces ,chemistry.chemical_compound ,Synovial Fluid ,medicine ,Humans ,Distribution (pharmacology) ,Hydroxytriazolam ,Redistribution (chemistry) ,medicine.drug - Published
- 2021
4. A fatal case involved in pyrethroid insecticide ingestion: quantification of tetramethrin and resmethrin in body fluids of a deceased by LC–MS/MS
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Kanako Watanabe, Osamu Suzuki, Koutaro Hasegawa, Kayoko Minakata, Takuya Kitamoto, Masako Suzuki, Hideki Nozawa, and Itaru Yamagishi
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Detection limit ,Insecticides ,Chromatography ,Biochemistry (medical) ,Urine ,Toxicology ,Resmethrin ,Body Fluids ,Pathology and Forensic Medicine ,Eating ,chemistry.chemical_compound ,chemistry ,Tandem Mass Spectrometry ,Pyrethrins ,Lc ms ms ,Humans ,Ingestion ,Female ,Pyrethroid insecticide ,Tetramethrin ,Chromatography, Liquid ,Whole blood - Abstract
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). 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. 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 ℃. To our knowledge, this is the first report for quantification of unchanged tetramethrin and resmethrin in human specimens obtained in a fatal case.
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- 2021
5. In Vivo Metabolites of AB-PINACA in Solid Tissues Obtained from Its Abuser: Comparison with In Vitro Experiment
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Osamu Suzuki, Kanako Watanabe, Kayoko Minakata, Takuya Kitamoto, Masako Suzuki, Koutaro Hasegawa, Itaru Yamagishi, and Hideki Nozawa
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Indazoles ,Health, Toxicology and Mutagenesis ,Metabolite ,Glucuronidation ,Urine ,Toxicology ,01 natural sciences ,Gas Chromatography-Mass Spectrometry ,Analytical Chemistry ,Hydroxylation ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Tandem Mass Spectrometry ,In vivo ,medicine ,Humans ,Environmental Chemistry ,030216 legal & forensic medicine ,Kidney ,Chemical Health and Safety ,Chromatography ,Cannabinoids ,Illicit Drugs ,010401 analytical chemistry ,Valine ,Body Fluids ,0104 chemical sciences ,Substance Abuse Detection ,medicine.anatomical_structure ,chemistry ,Hepatocytes ,Microsomes, Liver ,Microsome ,Autopsy ,Chromatography, Liquid ,Homogenization (biology) - Abstract
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 β-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.
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- 2020
6. In vitro and in vivo human metabolism of a synthetic cannabinoid EAM-2201 detected by LC–quadrupole-ion trap-MS/MS and high-resolution LC–Orbitrap-MS/MS
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Kayoko Minakata, Takuya Kitamoto, Kanako Watanabe, Koutaro Hasegawa, Hideki Nozawa, Masako Suzuki, Itaru Yamagishi, and Osamu Suzuki
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Chromatography ,Metabolite ,010401 analytical chemistry ,Biochemistry (medical) ,Glucuronidation ,Urine ,Toxicology ,Tandem mass spectrometry ,01 natural sciences ,In vitro ,0104 chemical sciences ,Pathology and Forensic Medicine ,Hydroxylation ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,medicine.anatomical_structure ,chemistry ,In vivo ,Hepatocyte ,medicine ,030216 legal & forensic medicine - Abstract
The aim of this study is to characterize the metabolites of EAM-2201 in human hepatocytes obtained in vitro and those in liver and urine specimens obtained in vivo from the autopsy of an EAM-2201 abuser. EAM-2201 was incubated with human hepatocytes for 3 h in a CO2 incubator and the metabolites of EAM-2201 were produced. The human liver specimen was homogenized and the metabolites were extracted. The urine specimen was hydrolyzed first with β-glucuronidase and the metabolites were extracted. The tentative detection and identification of those metabolites were performed using liquid chromatography (LC)–quadrupole-ion trap tandem mass spectrometry (MS/MS) and high-resolution LC–Orbitrap-MS/MS, respectively. Twelve metabolites of EAM-2201 could be characterized in hepatocytes, liver and urine. They were produced by defluorination, hydroxylation, carboxylation, dehydrogenation, N-dealkylation and/or glucuronidation of EAM-2201. The most detectable metabolite obtained from the in vitro hepatocyte incubation was that monohydroxylated at the 4-ethylnaphthalene moiety of EAM-2201 after dehydrogenation. However, only a trace amount of the same metabolite was detected in the liver tissue obtained postmortem from an EAM-2201 abuser. In the liver tissue, the highest metabolite was 5-carboxypentyl derivative of EAM-2201, which was monohydroxylated at the 4-ethylnaphthalene moiety, followed by monohydroxylpentyl and monohydroxy-4-ethylnaphthalenyl derivative of EAM-2201 without dehydrogenation. Twelve metabolites of a synthetic cannabinoid, EAM-2201, were tentatively identified in human hepatocytes in vitro, and in human liver and urine specimens in vivo for the first time. There was a distinct difference in metabolism profile between the in vitro and in vivo results.
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- 2019
7. Quantification of clitidine in caps and stems of poisonous mushroom Paralepistopsis acromelalga by hydrophilic interaction liquid chromatography–tandem mass spectrometry
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Kayoko Minakata, Itaru Yamagishi, Amin Wurita, Katsuhiro Konno, Kimiko Hashimoto, Osamu Suzuki, Hideki Nozawa, Kanako Watanabe, Koutaro Hasegawa, and Kunio Gonmori
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Mushroom ,Chromatography ,Chemistry ,Hydrophilic interaction chromatography ,010401 analytical chemistry ,Biochemistry (medical) ,Toxicology ,Mass spectrometry ,Tandem mass spectrometry ,01 natural sciences ,0104 chemical sciences ,Pathology and Forensic Medicine ,Dilution ,03 medical and health sciences ,0302 clinical medicine ,Standard addition ,Poisonous mushroom ,030216 legal & forensic medicine ,Quantitative analysis (chemistry) - Abstract
A simple and high-throughput analytical method for determining clitidine in Paralepistopsis acromelalga using hydrophilic interaction liquid chromatography–tandem mass spectrometry (LC–MS/MS) was established. To determine clitidine in the mushrooms, a simple procedure including dilution with methanol solution and filtering by cartridge was employed just before quantification by LC–MS/MS for high-throughput analysis. In this report, concentrations of clitidine in mushrooms were determined by the standard addition method. The present established method was successfully applied to the analysis of fruit bodies of P. acromelalga, which were obtained from five different locations in Japan. Results on concentrations of clitidine in each stem and cap of P. acromelalga specimens tested showed that their concentrations were quite different, not only between stems and caps, but also among locations and strains; the concentrations of clitidine in stems and caps ranged from 1.41 to 9.30 mg/g and 3.17 to 14.4 mg/g, respectively. This is the first report to present a detailed quantitative analysis of clitidine by MS and the distribution of clitidine in stems and caps of P. acromelalga. This analytical method for clitidine was thought to be useful in P. acromelalga poisoning cases to identify the causative toxic mushroom.
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- 2019
8. Quantification of Major Metabolites of AB-FUBINACA in Solid Tissues Obtained from an Abuser
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Osamu Suzuki, Kayoko Minakata, Hideki Nozawa, Masako Suzuki, Koutaro Hasegawa, Takuya Kitamoto, Kanako Watanabe, and Itaru Yamagishi
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Kidney ,Chemical Health and Safety ,Chromatography ,Indazoles ,Health, Toxicology and Mutagenesis ,Metabolite ,Urine ,Toxicology ,Orbitrap ,Mass spectrometry ,In vitro ,Mass Spectrometry ,Analytical Chemistry ,law.invention ,chemistry.chemical_compound ,medicine.anatomical_structure ,chemistry ,In vivo ,law ,AB-FUBINACA ,medicine ,Microsomes, Liver ,Environmental Chemistry ,Humans ,Chromatography, Liquid - Abstract
AB-FUBINACA M3 was reported to be a major metabolite of the drug, but its in vivo concentration in authentic human solid tissues has not been quantified yet. Another metabolite AB-FUBINACA M4 did not receive much attention previously and also has not been quantified yet in any authentic human specimens. The aims of this study are to establish a sensitive method for quantification of M3 and M4 in solid tissues and to compare the metabolite profile of AB-FUBINACA in authentic human specimens in vivo with that produced by human hepatocytes in vitro. The quantification was performed by liquid chromatography (LC)–quadrupole-ion trap-tandem mass spectrometry (MS-MS), and the characterization by LC–quadrupole Orbitrap MS-MS The limits of quantification of M3 were 10 pg/mL and 60 pg/g, and those of M4 were 100 pg/mL and 600 pg/g in urine and tissues, respectively. In the present work, M3 and M4 were identified and quantified in human lung, liver and kidney obtained from a cadaver for the first time; the concentrations of M3 were 226, 255, 202 and 155 pg/mL or g, and those of M4 14,400, 768, 637 and 1,390 pg/mL or g in urine, lung, liver and kidney, respectively. The peak intensity profiles of seven metabolites in these specimens were compared with that produced by human hepatocytes; the top three metabolites in urine specimen were completely different from those of hepatocytes. M3 was reported as the predominant metabolite in several previous works and M4 was listed as a minor metabolite in only one work, but, in this work, M4 has been found to be the major metabolite in all of the authentic urine, lung, liver and kidney specimens. The M3 plus M4 metabolites in lung or kidney were found most recommendable to prove AB-FUBINACA consumption, when urine specimen is lacking.
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- 2020
9. Sensitive quantification of 5F-NNEI and characterization of its several metabolites in authentic urine and/or serum specimens obtained from three individuals by LC–QTRAP-MS/MS and high-resolution LC–Orbitrap-MS/MS
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Osamu Suzuki, Koutaro Hasegawa, Atsuto Yoshino, Kayoko Minakata, Hideki Nozawa, Kanako Watanabe, Masako Suzuki, Takeji Saitoh, Takuya Kitamoto, and Itaru Yamagishi
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Detection limit ,Chromatography ,Chemistry ,010401 analytical chemistry ,Biochemistry (medical) ,Pharmacology toxicology ,Orbitrap ms ,High resolution ,Urine ,Toxicology ,Tandem mass spectrometry ,01 natural sciences ,0104 chemical sciences ,Pathology and Forensic Medicine ,03 medical and health sciences ,0302 clinical medicine ,030216 legal & forensic medicine - Abstract
A synthetic cannabinoid 5F-NNEI and its metabolites in authentic human specimens have not been reported yet. The aim of this study is, firstly, to establish a sensitive quantification method of 5F-NNEI in human serum and urine specimens, and, secondly, the characterization of its metabolites in authentic urine specimens obtained from three individuals. These compounds were extracted from β-glucuronide-hydrolyzed and unhydrolyzed urine and/or serum specimens via liquid-liquid extraction. The identification and quantification were performed using liquid chromatography (LC)–QTRAP tandem mass spectrometry (MS/MS), and the characterization of the metabolites was done using LC–high-resolution-MS/MS. The limits of detection for unchanged 5F-NNEI were 6 pg/mL with the quantification range of 10–2000 pg/mL in serum, and 3 pg/mL with the quantification range of 5–1000 pg/mL in urine. The devised method was applied to quantify 5F-NNEI in authentic serum and/or urine specimens from three individuals. The levels of 5F-NNEI were 11.6 and 3680 pg/mL in serum specimens of cases 1 and 2, respectively, and were 5.07 and 7.90 pg/mL in urine specimens of cases 2 and 3, respectively. Several metabolites of 5F-NNEI produced by amide hydrolysis, defluorination, hydroxylation, carboxylation and/or glucuronization were tentatively identified in the urine specimens by the LC–high-resolution-MS/MS. A synthetic cannabinoid, 5F-NNEI, was identified and quantified in its unchanged form, and its several metabolites were tentatively identified in authentic specimens obtained from three individuals, for the first time to our knowledge.
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- 2018
10. Sensitive quantification of 5F-PB-22 and its three metabolites 5F-PB-22 3-carboxyindole, B-22 N-5-hydroxypentyl and PB-22 N-pentanoic acid in authentic urine specimens obtained from four individuals by liquid chromatography–tandem mass spectrometry
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Ruri Kikura-Hanajiri, Kayoko Minakata, Masako Suzuki, Hideki Nozawa, Koutaro Hasegawa, Itaru Yamagishi, Kanako Watanabe, Takuya Kitamoto, and Osamu Suzuki
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Detection limit ,Chromatography ,Chemistry ,010401 analytical chemistry ,Biochemistry (medical) ,Extraction (chemistry) ,Urine ,Toxicology ,Mass spectrometry ,01 natural sciences ,0104 chemical sciences ,Pathology and Forensic Medicine ,03 medical and health sciences ,0302 clinical medicine ,Liquid chromatography–mass spectrometry ,PB-22 ,Synthetic cannabinoids ,medicine ,030216 legal & forensic medicine ,Quantitation Range ,medicine.drug - Abstract
Urine is the most suitable specimen to collect from individuals because of noninvasiveness and relatively large volumes obtainable. In authentic urine specimens, however, synthetic cannabinoids having the structures of quinolinyl ester indoles, such as 5F-PB-22, PB-22 and BB-22, in unchanged forms as well as their metabolites, have not been quantified yet. Therefore, the aim of this study was to establish a sensitive analytical method for the quantification of 5F-PB-22 and its three metabolites 5F-PB-22 3-carboxyindole, PB-22 N-5-hydroxypentyl and PB-22 N-pentanoic acid in authentic urine samples in four cases. These compounds were extracted from β-glucuronide-hydrolyzed and unhydrolyzed urine via liquid-liquid extraction. The identification and quantification were performed using the QTRAP type of a liquid chromatography–tandem mass spectrometer. The limits of detection were 3–30 pg/mL and their summed quantitation range was 10–10,000 pg/mL. The devised method was applied to quantify these compounds in authentic urine specimens obtained from four individuals. The levels of 5F-PB-22 were 5.1, 13.6, 94.7 and 470 pg/mL; those of 5F-PB-22 3-carboxyindole were 8.25, 3.39, 23.2 and 880 ng/mL; and those of PB-22 N-pentanoic acid were 12.0, 57.4, 959 and 2090 pg/mL, respectively, in four unhydrolyzed urine samples, and the levels of PB-22 N-5-hydroxypentyl could be quantified as 29.9 and 131 pg/mL in two unhydrolyzed urine samples. The 5F-PB-22 and its metabolites PB-22 N-5-hydroxypentyl have been detected from authentic human urine samples for the first time. Also, this is the first report dealing with the quantification of the three metabolites in human urine samples.
- Published
- 2017
11. Sensitive identification and quantitation of parent forms of six synthetic cannabinoids in urine samples of human cadavers by liquid chromatography–tandem mass spectrometry
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Kayoko Minakata, Koutaro Hasegawa, Hideki Nozawa, Itaru Yamagishi, Kanako Watanabe, Masako Suzuki, Kunio Gonmori, and Osamu Suzuki
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Detection limit ,Chromatography ,Chemistry ,010401 analytical chemistry ,Biochemistry (medical) ,Urine ,Toxicology ,Mass spectrometry ,01 natural sciences ,0104 chemical sciences ,Pathology and Forensic Medicine ,AB-CHMINACA ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,AB-PINACA ,Liquid chromatography–mass spectrometry ,Synthetic cannabinoids ,medicine ,030216 legal & forensic medicine ,Quantitation Range ,medicine.drug - Abstract
Human urine samples are easier to obtain than human blood samples due to noninvasiveness. The urine levels of synthetic cannabinoids (SCs) in unchanged forms, however, are usually much lower than their blood and tissue levels and cannot be detected in most cases. Therefore, in the present work a sensitive analytical method was devised for the determination of urine levels of six SCs in unchanged forms such as N-(1-amino-3-methy-1-oxobutan-2-yl)-1-pentyl-1H-indazole-3-carboxamide (AB-PINACA), N-(1-amino-3-methy-1-oxobutan-2-yl)-1-(4-fluorobenzyl)-1H-indazole-3-carboxamide (AB-FUBINACA), N-[(1S)-1-(1-aminocarbonyl)-2-methyl-propyl]-1-(cyclohexylmethyl)-1H-indazole-3-carboxamide (AB-CHMINACA), N-(1-amino-3,3-dimethyl-1-oxobutan-2-yl)-1-(cyclohexylmethyl)-1H-indazole-3-carboxamide (MAB-CHMINACA), methyl-2-[1-(5-fluoropentyl)-1H-indazole-3-carboxamido]-3-methylbutanoate (5F-AMB) and methyl-2-[1-(5-fluoropentyl)-1H-indazole-3-carboxamido]-3,3-dimethylbutanoate (5F-ADB). These SCs were extracted from urine via liquid–liquid extraction. The identification and quantitation were performed by a relatively new type of an instrument for liquid chromatography–tandem mass spectrometry. The limits of detection were as low as 3–8 pg/mL, and the quantitation range was 10–1000 pg/mL using 400 μL of urine. The urine levels of AB-PINACA and AB-FUBINACA of victim 1 were 23 and 10 pg/mL, those of AB-CHMINACA and 5F-AMB of victim 2 were 239 and 19 pg/mL, and those of MAB-CHMINACA and 5F-ADB of victim 3 were 229 and 19 pg/mL, respectively. To our knowledge, this is the first report dealing with successful analysis of low levels of parent synthetic cannabinoids in authentic human urine specimens.
- Published
- 2017
12. Quantitation of biperiden in whole blood by MALDI-QTOF tandem mass spectrometry, and estimation of new metabolites in urine of deceased subjects treated with biperiden antemortem
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Kunio Gonmori, Itaru Yamagishi, Kayoko Minakata, Hideki Nozawa, Koutaro Hasegawa, Kanako Watanabe, Masako Suzuki, and Osamu Suzuki
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Detection limit ,Chromatography ,Chemistry ,010401 analytical chemistry ,Biochemistry (medical) ,Urine ,Toxicology ,Tandem mass spectrometry ,Mass spectrometry ,01 natural sciences ,Biperiden ,0104 chemical sciences ,Pathology and Forensic Medicine ,Antiparkinson drug ,03 medical and health sciences ,0302 clinical medicine ,medicine ,030216 legal & forensic medicine ,Quantitation Range ,medicine.drug ,Whole blood - Abstract
In this work, the application of matrix-assisted laser desorption ionization (MALDI)-quadrupole time-of-flight (QTOF)-tandem mass spectrometry (MS/MS) to the quantitation of the anticholinergic/antiparkinson drug biperiden in human whole blood, and the estimation of new phase I metabolites of biperiden in human urine, were performed for the first time. The limit of detection of biperiden in human whole blood was 0.3 ng/mL with a quantitation range of 1–100 ng/mL using 20 μL each of whole blood. The developed method was successfully applied to the determination of biperiden in whole blood obtained from two deceased subjects having a history of biperiden treatment. The concentrations of biperiden in the whole blood samples were 1.7 and 17.5 ng/mL. The MALDI-QTOF-MS/MS method was also used to estimate the metabolites of biperiden in urine obtained from the subjects. Six new metabolites formed by hydroxylation and/or dehydration were detected.
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- 2016
13. Application of MALDI-QTOF mass spectrometry to the determination of timiperone in whole blood, and estimation of its new metabolites in urine of a deceased subject who had been treated with timiperone antemortem
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Koutaro Hasegawa, Hideki Nozawa, Kunio Gonmori, Kanako Watanabe, Masako Suzuki, Osamu Suzuki, Itaru Yamagishi, and Kayoko Minakata
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Detection limit ,Desorption ionization ,Chromatography ,Timiperone ,Butyrophenone ,010401 analytical chemistry ,Biochemistry (medical) ,Urine ,Toxicology ,Mass spectrometry ,01 natural sciences ,0104 chemical sciences ,Pathology and Forensic Medicine ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,chemistry ,medicine ,030216 legal & forensic medicine ,Quantitation Range ,Whole blood ,medicine.drug - Abstract
Application of matrix-assisted laser desorption ionization (MALDI) quadrupole time-of-flight (QTOF)-mass spectrometry (MS) to the determination of timiperone and estimation of its phase I metabolites were performed for the first time. The limit of detection of timiperone in human whole blood was 1 ng/mL with a quantitation range of 2–100 ng/mL using 20 μL each of whole blood. The developed method was successfully applied to the determination of timiperone in whole blood obtained from a deceased subject that had a history of timiperone treatment. The concentration of timiperone in whole blood of the victim was 3.98 ng/mL. Moreover, the MALDI-QTOF-MS/MS method was also used for detection of new metabolites of timiperone in urine also obtained from this victim. Five new metabolites were detected, which were formed via exchange of S for O, deletion of S, carbonyl reduction, hydroxylation, and a combination of them. Most likely, some of the newly detected metabolites seem pharmacologically active because they retain butyrophenone structures.
- Published
- 2016
14. Simultaneous determination of cyclic antidepressants and their related drugs and the estimation of new metabolites in human whole blood and urine by MALDI-QTOF-mass spectrometry
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Kayoko Minakata, Kunio Gonmori, Itaru Yamagishi, Kanako Watanabe, Osamu Suzuki, Hideki Nozawa, Masako Suzuki, and Koutaro Hasegawa
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chemistry.chemical_classification ,Chromatography ,Metabolite ,010401 analytical chemistry ,Biochemistry (medical) ,Pharmacology ,Toxicology ,Mianserin ,Mass spectrometry ,01 natural sciences ,Imipramine ,0104 chemical sciences ,Pathology and Forensic Medicine ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,chemistry ,medicine ,Amitriptyline ,030216 legal & forensic medicine ,Nortriptyline ,medicine.drug ,Whole blood ,Tricyclic - Abstract
A rapid and sensitive method using matrix-assisted laser desorption ionization (MALDI)-quadrupole time-of-flight (QTOF)-mass spectrometry (MS) was developed for the analysis of six tricyclic antidepressants (ADs) and their related drugs, such as amitriptyline, carbamazepine, clomipramine, imipramine, nortriptyline, quetiapine, and two tetracyclic ADs, mianserin and mirtazapine, because these eight drugs are commonly observed medicines in poisoning cases in Japan. In the present MALDI-MS method, the limits of detection were 0.3–2 ng/mL. The present method provided a simple and high throughput simultaneous analysis of these drugs. This is the first report dealing with quantitation of ADs and their related drugs in biological samples by MALDI-MS. In addition, we applied the MALDI-MS to two authentic cases, and three new metabolites of amitriptyline and three new metabolites of quetiapine could be detected in blood and urine samples in the two cases when regioisomers were counted as one metabolite.
- Published
- 2016
15. Postmortem redistribution of methamphetamine and amphetamine in blood specimens from various blood vessels and in the specimens from pericardial fluid, bile, stomach contents and various solid tissues collected from a human cadaver
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Osamu Suzuki, Kanako Watanabe, Koutaro Hasegawa, Hideki Nozawa, Itaru Yamagishi, Amin Wurita, Kayoko Minakata, and Kunio Gonmori
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Pathology ,medicine.medical_specialty ,Metabolite ,Femoral vein ,Toxicology ,01 natural sciences ,Pathology and Forensic Medicine ,Pulmonary vein ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,medicine ,030216 legal & forensic medicine ,Vein ,business.industry ,Stomach ,010401 analytical chemistry ,Biochemistry (medical) ,Pericardial fluid ,Venous blood ,Methamphetamine ,0104 chemical sciences ,medicine.anatomical_structure ,chemistry ,business ,medicine.drug - Abstract
We recently encountered an autopsy case in which methamphetamine (MA) was involved. The postmortem interval was estimated to be as long as 6–7 days. We collected the blood specimens from 9 locations of the heart and blood vessels, and specimens from pericardial fluid, bile, stomach contents and 9 solid tissues (in total 21 specimens), which were subjected to analysis of MA and the metabolite amphetamine by liquid chromatography–tandem mass spectrometry after a modified QuEChERS extraction. The highest concentration of MA was found for the stomach contents, suggesting the oral ingestion of MA. Among the blood specimens, their MA concentrations varied from 268 to 911 ng/mL. The concentration of MA in the left heart blood was higher than that in the right heart blood. In spite of this, the MA concentration in the pulmonary vein was much lower than that in the left heart blood. The comparison of MA concentrations in venous blood vessels showed that MA concentration was highest in the vena cava, followed by the iliac vein, and was lowest in the femoral vein, suggesting that MA concentration is decreased by diffusion across the thin walls of venous blood vessels during the postmortem interval. The partial loss of a xenobiotic by diffusion via the thin wall of the femoral vein should be taken into consideration especially when the postmortem interval is relatively long.
- Published
- 2015
16. Semiquantitation of diphenidine in tissue sections obtained from a human cadaver in a poisoning case by direct MALDI-QTOF mass spectrometry
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Amin Wurita, Itaru Yamagishi, Kayoko Minakata, Koutaro Hasegawa, Hideki Nozawa, Masako Suzuki, Osamu Suzuki, Kunio Gonmori, and Kanako Watanabe
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Chromatography ,Chemistry ,Diphenidine ,010401 analytical chemistry ,Biochemistry (medical) ,Analytical chemistry ,Adipose tissue ,Repeatability ,Toxicology ,Mass spectrometry ,01 natural sciences ,0104 chemical sciences ,Pathology and Forensic Medicine ,Matrix (chemical analysis) ,03 medical and health sciences ,0302 clinical medicine ,Tissue sections ,Standard addition ,030216 legal & forensic medicine ,Quantitative analysis (chemistry) - Abstract
Diphenidine [1-(1,2-diphenyl-ethyl)piperidine] in the tissue sections of the adipose, brain, heart, kidney, and liver obtained from a human cadaver in a poisoning case was directly analyzed as the first trial by matrix-assisted laser desorption ionization (MALDI)-quadrupole time-of-flight mass spectrometry (QTOF-MS). The frozen tissue block of approximately 5 × 5 × 5 mm3 was sectioned to a thickness of 10 or 20 μm at −20 or −35 °C. For quantitation, the reference standard solutions of diphenidine were placed at 0, 0.1, 1, and 10 ng/well on the wells of a MALDI sample plate firstly, and about 20 tissue sections (ca. 5 × 5 mm2 each) were placed on the sample plate secondly, followed by detection by MALDI-MS/MS after desiccation of the tissue sections and spraying α-cyano-4-hydroxycinnamic acid as the matrix. The quantitation was performed by the standard addition method without the use of blank human tissues. The correlation coefficients between the concentrations of diphenidine and the relative signal intensities were from 0.937 to 0.994 for five kinds of tissue. The suppression of signals by tissue was increased in the order of adipose tissue
- Published
- 2015
17. Postmortem distribution of MAB-CHMINACA in body fluids and solid tissues of a human cadaver
- Author
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Kayoko Minakata, Kunio Gonmori, Hideki Nozawa, Koutaro Hasegawa, Kanako Watanabe, Amin Wurita, Itaru Yamagishi, and Osamu Suzuki
- Subjects
Biochemistry, medical ,Pathology ,medicine.medical_specialty ,Kidney ,Chemistry ,Short Communication ,Biochemistry (medical) ,LC–MS–MS ,5-Fluoro-ADB ,Poison control ,Adipose tissue ,Pericardial fluid ,Toxicology ,Solid tissue ,Pathology and Forensic Medicine ,Postmortem distribution ,medicine.anatomical_structure ,Synthetic cannabinoids ,medicine ,Distribution (pharmacology) ,MAB-CHMINACA ,Synthetic cannabinoid ,Whole blood ,medicine.drug - Abstract
During the latter part of 2014, we experienced an autopsy case in which 5-fluoro-ADB, one of the most dangerous synthetic cannabinoids, was identified and quantitated in solid tissues and in three herbal blend products [Forensic Toxicol (2015) 33:112–121]. At that time, although we suspected that there may be some drug(s) other than 5-fluoro-ADB in the herbal products, all trials to find it/them were unsuccessful. Subsequently, we carefully re-examined the presence of other synthetic cannabinoid(s) in the above herbal blend products using accurate mass spectrometry and found two new compounds, 5-fluoro-ADB-PINACA and MAB-CHMINACA (Forensic Toxicol. doi: 10.1007/s 11419-015-0264-y). In the present communication, we report the distribution of MAB-CHMINACA in body fluids and solid tissue specimens collected from the same deceased individual (kept frozen at −80 °C) as described above for demonstration of 5-fluoro-ADB. Unexpectedly, unchanged MAB-CHMINACA could be identified and quantitated in whole blood and in pericardial fluid specimens, but it was below the detection limit (0.1 ng/ml) in the urine specimen. A higher concentration of MAB-CHMINACA could be found in all of the nine solid tissues; the highest concentration of MAB-CHMINACA was found in the liver (156 ng/g), followed by the kidney, pancreas and so on. The compounds were detected in all nine solid tissues; their levels were generally higher than those in the whole blood and pericardial fluid. Contrary to expectations, the concentration of MAB-CHMINACA in the adipose tissue was relatively low. Our results show that the victim smoked one of the three herbal blend products containing both MAB-CHMINACA and 5-fluoro-ADB, resulting in the coexistence of both compounds. It should be concluded that 5-fluoro-ADB and MAB-CHMINACA synergically exerted their toxicities, leading to death after a short interval. The differences in the distribution of 5-fluoro-ADB and MAB-CHMINACA among the cadaver specimens were also discussed in view of the structures of both compounds. To our knowledge, this is the first report to demonstrate MAB-CHMINACA in biological/human specimens.
- Published
- 2015
18. Identification and quantitation of 5-fluoro-ADB-PINACA and MAB-CHMINACA in dubious herbal products
- Author
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Kayoko Minakata, Amin Wurita, Koutaro Hasegawa, Kanako Watanabe, Itaru Yamagishi, Kunio Gonmori, Osamu Suzuki, and Hideki Nozawa
- Subjects
Chromatography ,Brand names ,Chemistry ,Biochemistry (medical) ,Analytical chemistry ,Toxicology ,Mass spectrometry ,Pathology and Forensic Medicine ,AB-CHMINACA ,chemistry.chemical_compound ,Standard addition ,Synthetic cannabinoids ,Mass spectrum ,medicine ,ADB-PINACA ,MAB-CHMINACA ,medicine.drug - Abstract
Police officials brought three different packages of herbal blends, with brand names “AL 37”, “AP 31”, and “GM sapphire”, to our laboratory for drug testing. Using our in-house high-resolution mass spectrometric analysis, we were able to estimate the presence of 5-fluoro-ADB-PINACA and MAB-CHMINACA in them without their reference standards. After obtaining the reference standards, we compared the mass spectra of the extracts of the herbal blends with those of the reference standards using both gas chromatography–mass spectrometry and liquid chromatography–tandem mass spectrometry. The mass spectra of the herbal blend extracts coincided with those of the reference standards, disclosing the presence of 5-fluoro-ADB-PINACA in “AL 37” and “AP 31”, and MAB-CHMINACA in “GM sapphire”. We then quantitated the concentrations of both compounds in the herbal blends using the standard addition method. The concentrations of 5-fluoro-ADB-PINACA were 19.4 ± 0.55 and 19.0 ± 0.47 mg/g (mean ± standard deviation of triplicate determinations) for herbal product brands “AL 37” and “AP 31”, respectively, and that of MAB-CHMINACA was 133 ± 4.5 mg/g for the “GM sapphire” herbal product. To our knowledge, this is the first study to demonstrate the identification and quantitation of the newest synthetic cannabinoids 5-fluoro-ADB-PINACA and MAB-CHMINACA in herbal blend products.
- Published
- 2015
19. Postmortem distribution of PV9, a new cathinone derivative, in human solid tissues in a fatal poisoning case
- Author
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Amin Wurita, Hideki Nozawa, Koutaro Hasegawa, Itaru Yamagishi, Kayoko Minakata, Osamu Suzuki, Kanako Watanabe, and Kunio Gonmori
- Subjects
Kidney ,Chromatography ,Chemistry ,Biochemistry (medical) ,Selected reaction monitoring ,Poison control ,Adipose tissue ,Urine ,Toxicology ,Quechers ,Pathology and Forensic Medicine ,medicine.anatomical_structure ,Psychotropic drug ,Standard addition ,medicine - Abstract
In our previous study, we identified PV9 [1-phenyl-2-(pyrrolidin-1-yl)octan-1-one] in human blood and urine in a fatal poisoning case. The victim was an 18-year-old woman. After ingesting “aroma liquid” solution, the victim showed various symptoms including low levels of consciousness, and was taken to a hospital emergency department. Although the victim received intensive medical treatment including an intravenous drip infusion of a large volume of transfusion solution, she was pronounced dead about 20 h after admission. In this study, we carefully examined the postmortem distribution of PV9 in nine solid tissues of the victim collected at forensic autopsy. The extraction of PV9 and internal standard (IS) PV8 [1-phenyl-2-(1-pyrrolidinyl)-1-heptanone] was performed by acetonitrile deproteinization, followed by modified QuEChERS dispersive solid-phase extraction and filtration through Captiva ND Lipids cartridges. Anaysis was performed by liquid chromatography–tandem mass spectrometry. Because this study dealt with various kinds of human matrices, we used the standard addition method to overcome matrix effects. After thorough validations, such as checking the product ion mass spectra, selected reaction monitoring chromatograms, linearity of the standard addition calibration curves, the intraday and interday repeatability, matrix effects, and recovery rates for the method, the concentrations of PV9 in nine solid tissue specimens were measured using PV8 as IS. The highest level of PV9 was found in the kidney at 907 ± 19.5 ng/g followed by the skeletal muscle, pancreas, adipose tissue, liver, lung, spleen, heart muscle, and brain. The lowest level of PV9 in the brain was 212 ± 11.9 ng/g. The high level of PV9 in the kidney suggests that this drug tends to be rapidly excreted into urine via the kidney as was the case for α-pyrrolidinovalerophenone. The low concentration of PV9 in the brain was unexpected, because this drug is a psychotropic drug with a long hydrophobic side chain, and is considered to cross the blood–brain barrier very easily. To our knowledge, this is the first demonstration of the distribution of the new pyrrolidinophenone derivative PV9 in human solid tissues in a poisoning case.
- Published
- 2014
20. Identification and quantitation of 5-fluoro-ADB, one of the most dangerous synthetic cannabinoids, in the stomach contents and solid tissues of a human cadaver and in some herbal products
- Author
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Kunio Gonmori, Koutaro Hasegawa, Osamu Suzuki, Hideki Nozawa, Amin Wurita, Kayoko Minakata, Kanako Watanabe, and Itaru Yamagishi
- Subjects
Detection limit ,Chromatography ,Lung ,Inhalation ,Chemistry ,Stomach ,Biochemistry (medical) ,Selected reaction monitoring ,Adipose tissue ,Context (language use) ,Urine ,Toxicology ,Pathology and Forensic Medicine ,medicine.anatomical_structure ,medicine - Abstract
Since late September 2014, there have been approximately 10 cases in Japan where people have died from inhaling smoke from herbal blends containing a newly emerged synthetic cannabinoid. Although the drug was tentatively identified by some drug-monitoring institutions as 5-fluoro-ADB, to our knowledge, its data have not been published in any scientific context. We recently encountered an autopsy case in which 5-fluoro-ADB was involved. The deceased was a 34-year-old man who was found dead in his room. The postmortem interval was estimated at 35–40 h. The direct cause of the death was asphyxia due to aspiration of stomach contents into the trachea, which likely took place during vomiting under low-consciousness conditions provoked by inhalation of the 5-fluoro-ADB smoke. The cadaver was subjected to autopsy at our department. Femoral vein blood, right heart blood, left heart blood, urine, stomach contents, and nine solid tissues including the adipose tissue were collected and frozen until analysis. The extraction of 5-fluoro-ADB and internal standard 5-fluoro-AMB was performed using a modified QuEChERS method plus filtration through Captiva ND Lipids cartridges, followed by liquid chromatography–tandem mass spectrometry (LC–MS–MS) analysis. Because this study dealt with various kinds of human matrices, we used the standard addition method for quantitation to overcome the matrix effects. The levels of 5-fluoro-ADB in the cadaver specimens were generally low; it could not be detected from blood or urine specimens. The levels of 5-fluoro-ADB in solid tissues were 1.17–7.95 ng/g. Because the highest levels were found for the adipose tissue and heart muscle, the final extracts of the adipose tissue and/or heart muscle were concentrated 10- and 200-fold to obtain product ion mass spectra of 5-fluoro-ADB using LC–MS–MS and its mass spectrum by gas chromatography–mass spectrometry, respectively. Both spectra completely coincided with those obtained from the reference standard 5-fluoro-ADB, confirming that the target compound was 5-fluoro-ADB. The quantitative results obtained by selected reaction monitoring of LC–MS–MS showed the highest level, at 7.95 ng/g, in the adipose tissue, followed by stomach contents, brain, heart muscle, pancreas, and spleen. For the lung, liver, kidney, and skeletal muscle, levels were below the quantitation limit (about 0.5 ng/g), although very small peaks above the detection limit (about 0.1 ng/g) could be observed for all of the above solid tissues. The low levels of 5-fluoro-ADB in the solid tissues were likely as a result of only a small amount of 5-fluoro-ADB incorporated into the body via the lungs due to the short period from the beginning of smoking the herb to the fatal asphyxia resulting from aspiration of a massive amount of stomach contents into the trachea under low-consciousness conditions. In addition, we measured the content of 5-fluoro-ADB in three packages, all of which were opened, that were found under a pillow near the deceased; their levels of 5-fluoro-ADB were 49.2 mg/g, 12.2 μg/g, and 0.77 μg/g. To our knowledge, this is the first reported identification and quantitation of 5-fluoro-ADB in human specimens and herbal products.
- Published
- 2014
21. Determination of new pyrrolidino cathinone derivatives, PVT, F-PVP, MPHP, PV8, PV9 and F-PV9, in human blood by MALDI-Q-TOF mass spectrometry
- Author
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Amin Wurita, Kayoko Minakata, Kunio Gonmori, Koutaro Hasegawa, Hideki Nozawa, Kanako Watanabe, Masako Suzuki, Itaru Yamagishi, and Osamu Suzuki
- Subjects
Detection limit ,Chromatography ,Cathinone ,Chemistry ,Metabolite ,Biochemistry (medical) ,Analytical chemistry ,Iminium ,Protonation ,Toxicology ,Mass spectrometry ,Pathology and Forensic Medicine ,Matrix (chemical analysis) ,chemistry.chemical_compound ,medicine ,Molecule ,medicine.drug - Abstract
A rapid and sensitive detection method using matrix-assisted laser desorption ionization (MALDI)–quadrupole time-of-flight–mass spectrometry (Q-TOF–MS) was developed for the analysis of six pyrrolidino cathinone derivatives, α-pyrrolidinopentiothiophenone (PVT), 4′-fluoro-α-pyrrolidinopentiophenone (F-PVP), 4′-methyl-α-pyrrolidinohexanophenone (MPHP), α-pyrrolidinoheptanophenone (PV8), α-pyrrolidinooctanophenone (PV9) and 4′-fluoro-α-pyrrolidinooctanophenone (F-PV9), that were newly designated as illegal drugs in Japan. In this method, α-cyano-4-hydroxycinnamic acid was used as the matrix to assist the ionization of cathinones. MS spectra of these cathinones showed a protonated molecule [M+H]+ and iminium, respectively, and hence the main ions of MALDI–MS were a mixture of the main ions detected by liquid chromatography–electrospray ionization–mass spectrometry and that by gas chromatography–electron ionization–mass spectrometry. The quantification of these cathinones was performed using α-pyrrolidinopentiophenone as the internal standard. The limit of detection was 1 ng/ml and the quantification range was 2–100 ng/ml for these cathinones using 20 μl of blood. We encountered a fatal poisoning case where PV9 was abused. The PV9 levels in postmortem blood samples from the right heart, left heart and femoral vein were 198, 209 and 163 ng/ml, respectively. The metabolites of PV9 were detected, and the peak height of an oxidized metabolite was higher than those of the protonated molecule and the other metabolites.
- Published
- 2014
22. Postmortem distribution of AB-CHMINACA, 5-fluoro-AMB, and diphenidine in body fluids and solid tissues in a fatal poisoning case: usefulness of adipose tissue for detection of the drugs in unchanged forms
- Author
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Kayoko Minakata, Kunio Gonmori, Amin Wurita, Osamu Suzuki, Itaru Yamagishi, Hideki Nozawa, Kanako Watanabe, and Koutaro Hasegawa
- Subjects
Body fluid ,Pathology ,medicine.medical_specialty ,Diphenidine ,Biochemistry (medical) ,Femoral vein ,Adipose tissue ,Autopsy ,Urine ,Toxicology ,Pathology and Forensic Medicine ,AB-CHMINACA ,chemistry.chemical_compound ,chemistry ,medicine ,Drug metabolism - Abstract
We encountered an autopsy case in which the cause of death was judged as poisoning by multiple drugs, including AB-CHMINACA, 5-fluoro-AMB, and diphenidine. The deceased was a 30-year-old man. The postmortem interval to autopsy was estimated to be 3.5 days. Femoral vein blood, right heart blood, left heart blood, urine, and eight solid tissues including adipose tissue were collected and frozen until analysis. Extraction of the three drugs, and internal standards phencyclidine and 5-fluoro-AB-PINACA was performed by a modified QuEChERS method, followed by analysis by liquid chromatography–tandem mass spectrometry. Because this study dealt with various kinds of human matrices, we used the standard addition method to overcome the matrix effects. Quantitation of all three compounds was only achieved for the adipose tissue, whereas the levels of 5-fluoro-AMB were below the lower limit of quantitation (about 1 ng/g or ml) in all other samples. AB-CHMINACA was quantitated for all solid tissues, but not for all body fluid specimens. Diphenidine showed high concentrations in all specimens; it was highest in the adipose tissue (11,100 ± 1,120 ng/g), an order of magnitude lower in other solid tissue specimens, and two orders of magnitude lower in body fluid samples. The results suggest that adipose tissue is the best specimen for detection of lipophilic drugs, such as AB-CHMINACA, 5-fluoro-AMB, and diphenidine, in their unchanged forms. In this poisoning case, diphenidine appeared to have played the major role in the cause of death, because the concentrations of diphenidine were much higher than those of the synthetic cannabinoids in all specimens tested. To our knowledge, this is the first report to document the presence of AB-CHMINACA, 5-fluoro-AMB, and diphenidine in actual postmortem specimens in a fatal poisoning case.
- Published
- 2014
23. MALDI–TOF mass spectrometric determination of four amphetamines in blood
- Author
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Amin Wurita, Koutaro Hasegawa, Kayoko Minakata, Masako Suzuki, Itaru Yamagishi, Hideki Nozawa, Kunio Gonmori, Osamu Suzuki, and Kanako Watanabe
- Subjects
Detection limit ,Chromatography ,Chemistry ,Biochemistry (medical) ,MDMA ,Urine ,Toxicology ,Mass spectrometry ,Mass spectrometric ,Cinnamic acid ,Pathology and Forensic Medicine ,Matrix (chemical analysis) ,chemistry.chemical_compound ,Ionization ,medicine ,medicine.drug - Abstract
A rapid and sensitive detection method using matrix-assisted laser desorption ionization time-of-flight mass spectrometry was developed for the analysis of amphetamine (A), methamphetamine (MA), 3,4-methylenedioxyamphetamine (MDA), and 3,4-methylenedioxymethamphetamine (MDMA). In this method, α-cyano-4-hydroxy cinnamic acid was used as the matrix to assist the ionization of amphetamines. The MS spectra of these amphetamines showed protonated molecules [M + H]+ and fragment ions with comparable or higher intensities. The quantifications of A and MA were performed using A-d 7 and MA-d 5 as the internal standard, respectively, and those of MDA and MDMA were performed using MDMA-d 5 as the internal standard. The limit of detection and the quantification range using 20 μl of blood were about 10 ng/ml and 30–500 ng/ml for A and MDA, respectively, and about 1 ng/ml and 3–50 ng/ml for MA and MDMA, respectively. In two cases of poisoning in which MA was abused, the levels of A in blood and urine were from 0.050 to 3.24 μg/ml and the levels of MA were from 0.231 to 25.1 μg/ml.
- Published
- 2014
24. MALDI-TOF mass spectrometric determination of four pyrrolidino cathinones in human blood
- Author
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Osamu Suzuki, Amin Wurita, Kayoko Minakata, Koutaro Hasegawa, Hideki Nozawa, Kanako Watanabe, Kunio Gonmori, Itaru Yamagishi, and Masako Suzuki
- Subjects
Detection limit ,Chromatography ,Human blood ,Pyrrolidino cathinones ,Chemistry ,medicine.drug_class ,α-Cyano-4-hydroxy cinnamic acid ,Biochemistry (medical) ,Polyatomic ion ,Protonation ,MALDI-TOF-mass spectrometry ,Toxicology ,Mass spectrometry ,Designer drugs ,Pathology and Forensic Medicine ,α-Pyrrolidinovalerophenone (α-PVP) ,Designer drug ,Blood ,Mass spectrum ,medicine ,Whole blood - Abstract
A rapid and sensitive detection method using matrix-assisted laser desorption ionization (MALDI) — time-of-flight (TOF) — mass spectrometry (MS) was developed for the analysis of four pyrrolidino cathinones, such as α-pyrrolidinopropiophenone (PPP), 4’-methyl-α-pyrrolidinopropiophenone (MPPP), α-pyrrolidinobutiophenone (PBP), and α-pyrrolidinovalerophenone (PVP). In this method, α-cyano-4-hydroxy cinnamic acid was used as the matrix to assist the ionization of cathinones. Each MALDI-TOF-MS spectrum of these cathinones showed not only protonated molecular ion [M + H]+, but also several fragment ions having comparable intensities to that of [M + H]+. Hence MPPP and PBP could be clearly discriminated by the mass spectra alone, although they have almost the same mass numbers in their protonated molecular ions. The quantification of MPPP, PBP or PVP was performed using PPP as internal standard, respectively, and that of PPP was performed using PBP as internal standard. The limit of detection was 1 ng/ml, and the quantification range was 2 – 200 ng/ml for the four cathinones using 20 μl of blood. In a fatal poisoning case in which PVP was abused, the PVP levels in whole blood samples obtained from the right heart, left heart and femoral vein were 0.597, 0.635 and 0.580 μg/ml, respectively. We recommend the MALDI-TOF-MS method without any chromatography for both identification and quantification of the pyrrolidino cathinones in various matrices in forensic toxicological analysis, because of the simplicity, rapidness and reliability of the method.
- Published
- 2014
25. Occurrence of postmortem production of ethylene glycol and propylene glycol in human specimens
- Author
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Itaru Yamagishi, Kunio Gonmori, Amin Wurita, Kayoko Minakata, Kanako Watanabe, Osamu Suzuki, Koutaro Hasegawa, and Hideki Nozawa
- Subjects
Human cadaver ,Chromatography ,Chemistry ,Biochemistry (medical) ,Diethylene glycol ,Urine ,Postmortem blood ,Toxicology ,Polyvinyl alcohol ,In vitro ,Pathology and Forensic Medicine ,chemistry.chemical_compound ,Biochemistry ,Ethylene glycol ,Whole blood - Abstract
We previously established a sensitive gas chromatography–mass spectrometry method for analysis of ethylene glycol (EG), propylene glycol (PG), and diethylene glycol (DEG), and disclosed the presence of appreciable amounts of EG, PG, and DEG in fresh whole blood and urine specimens obtained from nonoccupational healthy humans. These results led us to analyze EG and PG in specimens taken from three human cadavers. EG and PG concentrations in the postmortem blood and solid tissues were much higher than those found in fresh whole blood; their concentrations in many postmortem specimens were more than tenfold those in fresh whole blood specimens, suggesting the postmortem production of EG and PG. Therefore, we examined the time courses of EG and PG concentrations in blood specimens in the absence and presence of saprogenic blood (10 % volume) and/or glucose (3 mg/ml) in vitro, which were left at room temperature for 7 days. EG concentration in fresh blood without any addition decreased slightly during the 7 days. EG concentration in the blood with addition of glucose, and PG concentrations in the blood with and without addition of glucose did not change appreciably during the 7 days. EG and PG concentrations in the blood after addition of 10 % saprogenic blood increased 3.1-fold and 3.5-fold after 7 days, respectively; those after addition of saprogenic blood plus glucose increased 9.1-fold and 11.9-fold after 7 days, respectively. These results show that microorganisms present in the saprogenic blood caused the postmortem production of EG and PG, and the addition of glucose further enhances the EG and PG concentrations, probably acting as the substrate for glycol production by the microorganisms. To our knowledge, this is the first report to describe postmortem production of EG and PG in human specimens.
- Published
- 2013
26. Presence of appreciable amounts of ethylene glycol, propylene glycol, and diethylene glycol in human urine of healthy subjects
- Author
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Hideki Nozawa, Kayoko Minakata, Koutarou Hasegawa, Itaru Yamagishi, Amin Wurita, Kunio Gonmori, Osamu Suzuki, and Kanako Watanabe
- Subjects
Chromatography ,Biochemistry (medical) ,Healthy subjects ,Diethylene glycol ,Urine ,Isotope dilution ,Toxicology ,Polyvinyl alcohol ,Pathology and Forensic Medicine ,chemistry.chemical_compound ,chemistry ,Gas chromatography–mass spectrometry ,Ethylene glycol ,Whole blood - Abstract
In a previous study, we found that appreciable amounts of ethylene glycol (EG), propylene glycol (PG), and diethylene glycol (DEG) were present in the blood of nonoccupational healthy humans. In this study, we measured the three glycols in the urine of healthy subjects by the same isotope dilution gas chromatography–mass spectrometry method, and found the concentrations to be much higher than those in blood. The concentrations of EG, PG, and DEG in urine samples (mean ± standard deviation) obtained from 23 subjects at random were 604 ± 360, 5,450 ± 9,290, and 59.0 ± 49.3 ng/ml, respectively. These values were 9.44, 30.1, and 5.31 times higher than those in whole blood samples, respectively. The much higher concentrations of the three glycols found in urine samples of nonoccupational healthy humans suggest that the three glycols, once incorporated into the human body, are rapidly excreted into urine. To our knowledge, this is the first demonstration of the presence of relatively high concentrations of EG, PG, and DEG in urine of healthy human subjects.
- Published
- 2013
27. Sensitive determination of ethylene glycol, propylene glycol and diethylene glycol in human whole blood by isotope dilution gas chromatography–mass spectrometry, and the presence of appreciable amounts of the glycols in blood of healthy subjects
- Author
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Hideki Nozawa, Amin Wurita, Kayoko Minakata, Itaru Yamagishi, Osamu Suzuki, Kunio Gonmori, Koutaro Hasegawa, and Kanako Watanabe
- Subjects
Detection limit ,Chromatography ,Biochemistry (medical) ,Diethylene glycol ,Isotope dilution ,Toxicology ,Pathology and Forensic Medicine ,chemistry.chemical_compound ,chemistry ,Antifreeze ,Standard addition ,Gas chromatography–mass spectrometry ,Ethylene glycol ,Whole blood - Abstract
Ethylene glycol (EG), propylene glycol (PG), and diethylene glycol (DEG) are widely used as components of antifreeze liquids for automobiles and in many other products. They occasionally cause severe poisonings when they are ingested in high doses. In this study, we established a detailed procedure for highly sensitive and simultaneous determination of EG, PG, and DEG in human whole blood by isotope dilution gas chromatography–mass spectrometry (GC–MS). A 0.25-ml aliquot of whole blood containing the glycols was mixed with 100 ng each of deuterated EG, PG, and DEG as internal standards. After centrifugation, the supernatant fraction was evaporated to dryness, derivatized with heptafluorobutyric anhydride, and the derivative was extracted with n-hexane; 1 μl of the n-hexane layer was subjected to GC–MS analysis. Contrary to our expectation, appreciable amounts of EG, PG, and DEG were found, even in human whole blood samples obtained from nonoccupational healthy subjects. Because such results have never been reported, in the early stages of this study, we suspected that our results were caused by carry-over of the glycols during the GC–MS procedure; thus, we cleaned the injection port, installed a new GC column, and washed the ion-source chamber. Despite these efforts, the clear peaks were detected at the same retention times as those of the authentic glycols for the extracts of healthy subjects, which led us to confirm the presence of the glycols in the blood of healthy subjects. Because the blank whole blood samples from healthy subjects already contained glycols, we constructed a standard addition calibration curve for each sample; the horizontal intercept point, where the straight calibration line intersected the horizontal concentration axis, showed the background concentration of the glycol. The calibration curves showed linearity in the range of 0.4–400 ng/ml for EG and DEG, and in the range of 4–2,000 ng/ml for PG, with correlation coefficients larger than 0.99. The limits of detection and limits of quantitation could not be exactly determined, because of the unavailability of blank human whole blood without each glycol. However, the values were estimated to be around or lower than 1 ng/ml from the signal-to-noise ratios of peaks for each glycol at the lowest concentrations obtained by selected ion monitoring. To validate the method, intraday and interday repeatability was tested; the percent relative standard deviations were 2.5–12.2 % and 0.8–8.5 %, respectively. Recoveries of the three glycols using whole blood samples of two subjects obtained by a unique method were 61.6–80.9 %. The concentration ranges (mean) of EG, PG, and DEG in whole blood obtained from ten subjects were 39.1–97.0 (64.0), 49.1–689 (181), and 8.08–22.9 (11.1) ng/ml, respectively. To test the effect of oral intake of PG, two volunteers ingested 100 ml of a commercially available energy drink containing 33.7 mg of PG, the safety of which was accredited by the Japanese Government. The PG levels in the blood of the two subjects increased by 74.0 and 158 % at 1 and 0.5 h, respectively, suggesting that the glycols present in human blood are largely derived from food. To our knowledge, the analytical method for the glycols presented in this article is the most sensitive among those so far reported. In addition, this is the first description of the presence of the glycols in healthy human subjects, which should be useful for setting cutoff levels of the glycols in poisoning cases.
- Published
- 2013
28. Determination of ibotenic acid and muscimol, the Amanita mushroom toxins, in human serum by liquid chromatography–tandem mass spectrometry
- Author
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Osamu Suzuki, Koutaro Hasegawa, Itaru Yamagishi, Kanako Watanabe, Hideki Nozawa, Yoshito Kamijo, Hiroki Fujita, Kayoko Minakata, and Kunio Gonmori
- Subjects
Amanita ,Mushroom ,Chromatography ,biology ,Biochemistry (medical) ,Selected reaction monitoring ,Toxicology ,biology.organism_classification ,Pathology and Forensic Medicine ,chemistry.chemical_compound ,chemistry ,Muscimol ,Distilled water ,Liquid chromatography–mass spectrometry ,Trifluoroacetic acid ,Ibotenic acid - Abstract
In our previous article, we reported the analysis of ibotenic acid and muscimol in Amanita mushrooms by liquid chromatography–tandem mass spectrometry (LC–MS–MS). The levels of ibotenic acid and muscimol in the mushroom were as high as 210 and 107 μg/g, respectively. We have since tried to measure the same toxins in human serum obtained from a poisoned subject, who ingested the Amanita mushrooms, by the same method. However, the levels of the toxins in the human serum were about three orders of magnitude lower than those in Amanita mushrooms. In addition, the recovery rates for ibotenic acid and muscimol in human serum were found to be much lower than those in the previous study for the mushrooms. Therefore, we optimized the solid-phase extraction procedure again, and reevaluated the data for validation at much lower levels of ibotenic acid and muscimol in human serum. A 100-μl aliquot of human serum containing the target toxins was mixed with 100 ng of acivicin as internal standard (IS), 200 μl of distilled water, and 100 μl of 0.5 % ammonium hydroxide in distilled water, and vortexed well for 10 s. The mixture was loaded on an Oasis MAX 3cc (60 mg) extraction cartridge. The cartridge was washed with 0.5 ml of distilled water and 1.0 ml of methanol. The target compounds and IS were eluted with 4 ml of 0.05 % trifluoroacetic acid in methanol. The eluate was evaporated to dryness and reconstituted in methanol, and its small volume was subjected to LC–MS–MS analysis with the same TSK-GEL Amide-80 separation column. The LC elution was made in the gradient and isocratic modes. The selected reaction monitoring chromatograms showed clear peaks at 5.3, 3.5, and 3.6 min for ibotenic acid, muscimol, and IS, respectively; the blank serum sample without the target compounds or IS gave no peaks at the respective retention times except for an impurity peak at 6.5 min. There was good linearity from 10 to 1,000 ng/ml for both ibotenic acid and muscimol with correlation coefficients not
- Published
- 2013
29. MALDI-TOF mass spectrometric determination of 11 phenothiazines with heavy side chains in urine
- Author
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Koutaro Hasegawa, Kanako Watanabe, Kunio Gonmori, Amin Wurita, Itaru Yamagishi, Hideki Nozawa, Osamu Suzuki, Kayoko Minakata, and Masako Suzuki
- Subjects
Detection limit ,Chromatography ,Chemistry ,Biochemistry (medical) ,α-Cyano-4-hydroxy cinnamic acid (CHCA) ,Analytical chemistry ,MALDI-TOF mass spectrometry ,Protonation ,Urine ,Toxicology ,Mass spectrometry ,Pathology and Forensic Medicine ,Ion ,Matrix (chemical analysis) ,Phenothiazines ,Ionization ,Triflupromazine ,medicine ,medicine.drug - Abstract
A rapid screening method was developed for the determination of phenothiazines by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF–MS). In this method, α-cyano-4-hydroxy cinnamic acid (CHCA) was used as the matrix to assist the ionization of phenothiazines. The identification of 11 phenothiazines with heavy side chains was achieved by observing their protonated molecular ions [M+H]+ at m/z 340–447. Quantification was achieved by using triflupromazine at m/z 353 as the internal standard (IS). The relative ionization efficiencies of 11 phenothiazines and IS on MALDI-TOF–MS were different from those achieved by ESI-MS, but the product ion spectra from MALDI-MS–MS were quite similar to those from ESI-MS–MS except in the case of flupentixol. The limit of detection was 0.3 ng/ml with a quantification range of 1–50 ng/ml urine in the best case; the limit of detection was 5 ng/ml with a quantification range of 10–100 ng/ml urine in the worst case for 10 phenothiazines except thiethylperazine. The present method provides a simple and high-throughput method for the screening of these phenothiazines using only 20 μl of urine. To our knowledge, this study is the first trial to analyze phenothiazines by MALDI-TOF–MS (–MS).
- Published
- 2013
30. A new approach in tandem mass spectrometric simultaneous determination of perchlorate, thiocyanate and iodide using their ternary complexes with tris(1,10-phenanthroline) iron(II) chelate
- Author
-
Kayoko Minakata, Itaru Yamagishi, Koutaro Hasegawa, Hideki Nozawa, Masako Suzuki, Kunio Gonmori, Amin Wurita, Osamu Suzuki, and Kanako Watanabe
- Subjects
chemistry.chemical_classification ,Iodide ,Thiocyanate ,Chemistry ,Tandem mass spectrometry ,Phenanthroline ,Electrospray ionization ,Biochemistry (medical) ,Inorganic chemistry ,Selected reaction monitoring ,Perchlorate ,Toxicology ,Mass spectrometry ,Elecrospray ionization ,Pathology and Forensic Medicine ,chemistry.chemical_compound ,Chelation ,Tris (1,10-phenanthroline) iron (II) - Abstract
A rapid and sensitive method was developed for simultaneous determination of perchlorate (ClO4 −), thiocyanate (SCN−), and iodide (I−). The ions were reacted with tris(1,10-phenanthroline)iron(II) chelating cation, [Fe(phen)3]2+, to produce their ternary complexes, [Fe(phen)2ClO4]+, [Fe(phen)2SCN]+, and [Fe(phen)2I]+ that were extracted together with nitrobenzene. Five microliters of the extract was injected directly into an electrospray ionization tandem mass spectrometer. Quantification of ClO4 −, SCN−, and I− was performed by selected reaction monitoring of the product ion [Fe(phen)O2]+ at m/z 268 that derived from the precursor ion [Fe(phen)2ClO4]+ at m/z 515, the product ion [Fe(phen)SCN]+ at m/z 294 that derived from precursor ion [Fe(phen)2SCN]+ at m/z 474, and the product ion [Fe(phen)I]+ at m/z 363 that derived from precursor ion [Fe(phen)2I]+ at m/z 543, respectively. Perchlorate, SCN−, and I− were measured in the range of 0.1–10 μM with the limits of detection at 0.03 μM by using a 50-μl sample aliquot containing the three ions within 10 min. The SCN− level in gastric fluid of a victim of NaCN poisoning was 137 ± 23 μM, which is slightly higher than the results from control subjects (n = 7), 72 ± 39 μM.
- Published
- 2012
31. Analysis of ibotenic acid and muscimol in Amanita mushrooms by hydrophilic interaction liquid chromatography–tandem mass spectrometry
- Author
-
Kayoko Minakata, Kunio Gonmori, Hideki Nozawa, Hiroki Fujita, Koutaro Hasegawa, Osamu Suzuki, Itaru Yamagishi, Kanako Watanabe, and Yoshito Kamijo
- Subjects
Chromatography ,Formic acid ,Elution ,Hydrophilic interaction chromatography ,Biochemistry (medical) ,Selected reaction monitoring ,Toxicology ,Tandem mass spectrometry ,Pathology and Forensic Medicine ,chemistry.chemical_compound ,chemistry ,Muscimol ,Derivatization ,Ibotenic acid - Abstract
We have established the most modern method for analysis of ibotenic acid and muscimol in toxic Amanita mushrooms by liquid chromatography–tandem mass spectrometry (LC–MS–MS). Acivicin, an ibotenic acid analog and antitumor agent, was used as internal standard (IS). A target mushroom sample was homogenized in water/methanol (1:1) and mixed with a fixed concentration of IS. The target compounds and IS were purified with an Oasis MAX 3cc (60 mg) extraction cartridge. The eluate was subjected to hydrophilic interaction (TSK-GEL Amide-80 3 μm, 150 × 2.0 mm i.d. column) LC–MS–MS. The quantitation was made by multiple reaction monitoring (MRM). The ion transitions were: m/z 179→133.1 for IS, m/z 159→113.1 for ibotenic acid, and m/z 115→98.1 for muscimol. The elution was made in the gradient mode with 0.5 % formic acid aqueous solution (A) and 0.5 % formic acid in acetonitrile (B) from 90 % B to 80 % B in 1.85 min, and then in the isocratic elution mode with 20 % A/80 % B up to 10 min. The MRM chromatograms gave clear and symmetrical peaks for ibotenic acid, muscimol, and IS. Their recovery rates were 84.6–107 %. There was good linearity from 10 to 500 μg/g for both ibotenic acid and muscimol with correlation coefficients not
- Published
- 2012
32. MALDI-TOF mass spectrometric analysis of α-amanitin, β-amanitin, and phalloidin in urine
- Author
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Kunio Gonmori, Koutaro Hasegawa, Osamu Suzuki, Amin Wurita, Kayoko Minakata, Itaru Yamagishi, Masako Suzuki, Kanako Watanabe, and Hideki Nozawa
- Subjects
Detection limit ,Chromatography ,Phalloidin ,Sodium ,Biochemistry (medical) ,chemistry.chemical_element ,Toxicology ,Mass spectrometry ,Cinnamic acid ,Pathology and Forensic Medicine ,Adduct ,Matrix (chemical analysis) ,chemistry.chemical_compound ,chemistry ,polycyclic compounds ,Amanitin - Abstract
A rapid and sensitive method was developed for analysis of α-amanitin, β-amanitin, and phalloidin by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). In this method, α-cyano-4-hydroxy cinnamic acid was used as the matrix to assist the ionization of toxins. The identification of α-amanitin, β-amanitin, and phalloidin was achieved through their sodium adducts [M+Na]+ at m/z = 941, 942, and 811, and quantification of the three toxins was also achieved using microcystin RR at m/z = 1038 as internal standard. For all toxins, the limit of detection was 5 ng/ml, and all calibration curves were linear in the range of 10–500 ng/ml using 0.4 ml of urine. The sensitivity for identification was increased about tenfold when the tandem MS (MS–MS) mode was used for detection. Because these quantifications could be achieved in the toxin concentration range of 4–200 ng, the present MALDI-TOF MS method can serve as the most sensitive method so far reported for the analysis of these mushroom toxins. To our knowledge, this study is the first trial to analyze amanitins and phalloidin by MALDI-TOF MS (-MS).
- Published
- 2012
33. Simultaneous determination of coinage metals, copper, silver, and gold in tissues using electrospray ionization tandem mass spectrometry
- Author
-
Kunio Gonmori, Hideki Nozawa, Masako Suzuki, Itaru Yamagishi, Koutaro Hasegawa, Kayoko Minakata, Fumihiko Horio, Osamu Suzuki, and Kanako Watanabe
- Subjects
Detection limit ,Silver ,Tandem mass spectrometry ,Electrospray ionization ,Biochemistry (medical) ,Oxalic acid ,Inorganic chemistry ,chemistry.chemical_element ,Coinage metals ,Toxicology ,Isoamyl alcohol ,Copper ,Pathology and Forensic Medicine ,Ion ,chemistry.chemical_compound ,chemistry ,Diethyldithiocarbamate ,Gold - Abstract
A rapid and sensitive mass spectrometric method was developed for the simultaneous determination of the coinage metals of copper (Cu), silver (Ag), and gold (Au). The metals in a wet-ashed tissue solution were complexed with diethyldithiocarbamate (DDC; C4H10NCS2) and were extracted with isoamyl alcohol. After acidification of the extract with oxalic acid, metals were quantified using their product ions, Cu(DDCH)+, Ag(DDCH)+, and Au(DDCH)+ that derived from the precursor ions Cu(DDC) 2 + , Ag(DDC) 2 + , and Au(DDC) 2 + , respectively, by electrospray ionization tandem mass spectrometry. The limits of detection were 0.6, 0.3, and 1 μg/l for Cu, Ag, and Au, and the quantification ranges were 2–100, 1–100, and 3–100 μg/l for Cu, Ag, and Au, respectively. Cu levels in spontaneously hypertensive osteogenic disorder rats at 6 weeks of age and 30 weeks of age were found to be 1.8 times and 5.1 times those of the normotensive osteogenic disorder rats, respectively, when using wet-ashed kidney solutions diluted 1000-fold.
- Published
- 2012
34. A rapid and decisive determination of thiocyanate in blood by electrospray ionization tandem mass spectrometry
- Author
-
Hideki Nozawa, Kayoko Minakata, Kunio Gonmori, Itaru Yamagishi, Masako Suzuki, Koutaro Hasegawa, Kanako Watanabe, and Osamu Suzuki
- Subjects
Detection limit ,endocrine system ,animal structures ,Aqueous solution ,Chromatography ,Thiocyanate ,Electrospray ionization ,Biochemistry (medical) ,Selected reaction monitoring ,Toxicology ,Tandem mass spectrometry ,Mass spectrometry ,Pathology and Forensic Medicine ,Ion ,chemistry.chemical_compound ,nervous system ,chemistry ,sense organs ,hormones, hormone substitutes, and hormone antagonists - Abstract
A rapid and reliable method was developed to identify and quantify the thiocyanate ion (SCN−) in blood. SCN− was reacted with NaAuCl4 to produce Au(SCN)2−, which was extracted with octanol. The extract was injected directly into an electrospray ionization tandem mass spectrometer. Quantification of SCN− was performed by selected reaction monitoring of the product ion SCN− at m/z 58 that derived from the Au(SCN)2− precursor ion (m/z 313). SCN− could be measured in the quantification range of 0.05–10 μM in aqueous solution with a limit of detection of 0.013 μM within 15 min. Using only 5 μl of blood, the SCN− level of a victim who ingested sodium cyanide was determined to be 32.7 ± 2.1 μM, indicating a quite small increase from the control level of 15.5 ± 8.7 μM.
- Published
- 2011
35. Simultaneous analysis of sildenafil, vardenafil, tadalafil, and their desalkyl metabolites in human whole blood and urine by isotope dilution LC–MS–MS
- Author
-
Osamu Suzuki, Hideki Nozawa, Koutaro Hasegawa, Itaru Yamagishi, Kunio Gonmori, and Kanako Watanabe
- Subjects
Detection limit ,Chromatography ,Chemistry ,Sildenafil ,Biochemistry (medical) ,Selected reaction monitoring ,Urine ,Isotope dilution ,Pharmacology ,Toxicology ,Tadalafil ,Pathology and Forensic Medicine ,chemistry.chemical_compound ,Vardenafil ,medicine ,medicine.drug ,Whole blood - Abstract
Given that there are many autopsy cases in which erectile dysfunction (ED) treatment drugs can be detected from elderly men who are diagnosed to have died of cardiovascular disorders, the degree of cardiovascular risk posed by ED treatment drugs is still controversial. Moreover, counterfeit ED drugs or illegal dietary supplements containing ED drugs are also threats to public health. In this study, we established a detailed procedure for simultaneous analysis of typical ED drugs (sildenafil, vardenafil, tadalafil) and their metabolites in human blood and urine by isotope dilution liquid chromatography-tandem mass spectrometry (LC–MS–MS). Each sample of whole blood and urine containing the three ED treatment drugs, their metabolites, and deuterated internal standards (ISs) was diluted with alkalinized water, loaded onto an Oasis HLB cartridge, washed with dilute ammonium hydroxide solution, and eluted with chloroform. The eluate was acidified with methanol and concentrated HCl and evaporated to dryness. The resulting residue was reconstituted with methanol and mobile phase solution, and 5 μl of the solution was injected into an LC–MS–MS instrument. The determinations were made by multiple reaction monitoring using each product ion. The recovery rates of the drugs, metabolites, and ISs from whole blood and urine ranged from 80.7 to 127%. Good linearity was obtained for all drugs and their metabolites in the range of 1–100 ng/ml in whole blood and urine with correlation coefficients greater than 0.99. The detection limits (signal-to-noise ratio = 3) for all compounds were not higher than 0.05 ng/ml. Intraday and interday accuracy and precision data were also satisfactory for all compounds in whole blood and urine. Actual measurements of sildenafil and N-desmethyl sildenafil were also demonstrated by analysis of whole blood and urine specimens from two male volunteers after ingestion of a 25-mg tablet of sildenafil.
- Published
- 2011
36. Simple analysis of naphthalene in human whole blood and urine by headspace capillary gas chromatography with large volume injection
- Author
-
Osamu Suzuki, Kanako Watanabe, Koutaro Hasegawa, Itaru Yamagishi, and Hideki Nozawa
- Subjects
Detection limit ,Analyte ,Gas chromatography ,Chromatography ,Biochemistry (medical) ,Analytical chemistry ,1-Methylnaphtalene ,Urine ,Toxicology ,Mass spectrometry ,Pathology and Forensic Medicine ,law.invention ,Polycyclic aromatic hydrocarbon ,Large volume injection ,chemistry.chemical_compound ,chemistry ,law ,Headspace sampling ,Flame ionization detector ,Derivatization ,Naphthalene ,Whole blood - Abstract
A very simple method for the analysis of methamphetamine and amphetamine in human whole blood and urine by headspace gas chromatography (GC) has been presented. It neither needs solid-phase microextraction nor cryogenic trapping devices, but only a conventional capillary GC instrument with flame ionization detection (FID). The two special points to be mentioned in this method are the in-matrix derivatization of amphetamines for vaporization and the capability of injection of as large as 5 mL of the headspace vapor into a GC instrument in the splitless mode for sensitive detection. After heating a whole blood or urine sample containing amphetamines, α-methylbenzylamine (internal standard, IS) and heptafluoro-n-butyryl chloride under alkaline conditions in a 7.0-mL vial at 90 °C for 20 min, 5 mL of the headspace vapor was drawn with a glass syringe and injected into the gas chromatograph. During injection the column was at 40 °C to trap the analytes, and then the oven temperature was programmed up to 320 °C. Sharp peaks were obtained for each analyte and IS, and only a relatively small number of background impurity peaks for the whole blood and urine samples. The detection limits for each amphetamine were estimated to be 0.1 μg mL−1 for whole blood and 0.03 μg mL−1 for urine. Precision and linearity were also tested to confirm the reliability. Methamphetamine and amphetamine could be determined from whole blood and urine obtained at autopsy in three methamphetamine poisoning cases. The identity of each peak appearing in the gas chromatograms was confirmed by GC/mass spectrometry.
- Published
- 2009
37. Sensitive determination of arsenite and arsenate in plasma by electrospray ionization tandem mass spectrometry after chelate formation
- Author
-
Osamu Suzuki, Kayoko Minakata, Hideki Nozawa, Masako Suzuki, Kanako Watanabe, Itaru Yamagishi, Kunio Gonmori, Sanae Kanno, and Walid Husein Ali Ahmed
- Subjects
Aqueous solution ,Chromatography ,Electrospray ionization ,Biochemistry (medical) ,Selected reaction monitoring ,Arsenate ,chemistry.chemical_element ,Toxicology ,Tandem mass spectrometry ,Pathology and Forensic Medicine ,Methyl isobutyl ketone ,chemistry.chemical_compound ,chemistry ,Arsenic ,Arsenite - Abstract
Inorganic arsenite (As3+) and arsenate (As5+) are well-known poisons, and the toxicity of As3+ is about ten times that of As5+. In this study, a simple, rapid, and sensitive method was developed for As3+ in plasma using electrospray ionization (ESI) tandem mass spectrometry (MS-MS). After washing plasma with trichloroethylene (TCE), As3+ in the aqueous layer was reacted with pyrrolidinedithiocarbamate (PDC, C4H8NCSS-), and the produced As(PDC)3 was extracted with methyl isobutyl ketone (MIBK); a 1-µl aliquot of the MIBK layer containing As(PDC)3 was introduced into the MS-MS instrument in the direct-flow injection mode. Other arsenic compounds such as As5+, monomethyl arsonic acid, dimethyl arsinic acid, arsenobetaine, arsenocholine, and tetramethyl arsonium did not produce As(PDC)3. Therefore, without liquid chromatographic separation, As3+ alone could be detected after washing with TCE followed by solvent extraction of As(PDC)3 with MIBK. Thus, inorganic As5+ was reduced to As3+ with thiosulfate, and then the total inorganic As was quantifi ed as As3+; As5+could be calculated by subtracting As3+from the total inorganic As. The MS-MS quantification was performed by selected reaction monitoring using a peak at m/z 114 of a product ion (C4H8NCS)+ formed by collision-induced dissociation from the precursor ion As(PDC)2 + at m/z 367. The mass spectral identification on MS-MS spectrum was possible even at 1 ng As3+/ml plasma. The calibration curve for As3+ showed linearity from 0.5 to 100 ng/ml plasma. The limits of detection by selected reaction monitoring were 0.3 ng/ml in water and 0.2 ng/ml in plasma. The analysis could be completed in less than 15 min, because chromatographic separation was not necessary before the MS-MS detection.
- Published
- 2009
38. Determination of Urine Luck in urine using electrospray ionization tandem mass spectrometry
- Author
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Osamu Suzuki, Kunio Gonmori, Masako Suzuki, Hideki Nozawa, Sanae Kanno, Kayoko Minakata, Walid Husein Ali Ahmed, Itaru Yamagishi, and Kanako Watanabe
- Subjects
Detection limit ,Chromatography ,Calibration curve ,Electrospray ionization ,Biochemistry (medical) ,Selected reaction monitoring ,Urine ,Toxicology ,Isoamyl alcohol ,Tandem mass spectrometry ,Pathology and Forensic Medicine ,chemistry.chemical_compound ,chemistry ,Mass spectrum - Abstract
A simple, rapid and sensitive method using tandem mass spectrometry (MS-MS) has been developed for the determination of chromate Cr6+ in urine. Cr6+ is a substantial component of Urine Luck, which is used to conceal the presence of drugs in urine. Cr6+ was complexed with diethyldithiocarbamate (DDC) and extracted with isoamyl alcohol in the presence of citric acid. Then a 1-μl aliquot of isoamyl alcohol containing Cr-DDC complex was directly injected into an MS-MS instrument without chromatographic separation. The quantification was performed using selected reaction monitoring at m/z 363.8 of product ion CrO(DDC)2 + obtained by collision-induced dissociation from the precursor ion, CrOH(DDC)3 + at m/z 513.1. This method was validated with the analysis urine samples obtained from volunteers. A linear calibration curve could be obtained in the range of 0.18–100 ng/ml. The limits of detection and quantification of Cr6+ were 0.05 and 0.18 ng/ml, respectively, using only 10 μl of urine. Results could be obtained in less than 10 min for a sample. After oxidation of Cr3+ to Cr6+, near 100% recovery was confirmed using standard reference materials such as SRM 2670a (low level and high level) and SRM 1643e. The most outstanding advantage of this ESI-MS-MS method is that it gives excellent product ion mass spectra for identification of Cr6+.
- Published
- 2008
39. Trace analysis of platinum in blood and urine by ESI-MS-MS
- Author
-
Osamu Suzuki, Hideki Nozawa, Itaru Yamagishi, Masako Suzuki, Kunio Gonmori, Kayoko Minakata, and Kanako Watanabe
- Subjects
Chromatography ,Calibration curve ,Chemistry ,Electrospray ionization ,Biochemistry (medical) ,Selected reaction monitoring ,Oxalic acid ,chemistry.chemical_element ,Urine ,Toxicology ,Tandem mass spectrometry ,Isoamyl alcohol ,Pathology and Forensic Medicine ,chemistry.chemical_compound ,Platinum - Abstract
A simple, rapid, and sensitive method has been developed for determination of platinum (Pt) in blood and urine by tandem mass spectrometry (MS-MS). Pt4+ in wet-ashed blood or acid-treated urine was complexed with diethyldithiocarbamate (DDC), extracted with isoamyl alcohol, and acidified with oxalic acid; a 1-μl aliquot of the isoamyl alcohol layer containing the Pt-DDC complex was directly injected into the MS-MS instrument without chromatographic separation. The quantitation was performed using selected reaction monitoring at m/z 491 of the product ion Pt(DDC)2+, which was produced by collision-induced dissociation from the precursor ion Pt(DDC)3+ at m/z 639. This method was validated for the analysis of blood and urine samples; the limits of quantitation were about 0.3 and 0.1 ng/ml for blood and urine, respectively, using only 10 μl of sample. The calibration curves for Pt in urine and blood showed linearity from 0.1 to 30 ng/ml. Because chromatographic separation is not required before MS-MS detection, the analysis can be completed in less than 10 min.
- Published
- 2007
40. Platinum levels in various tissues of a patient who died 181 days after cisplatin overdosing determined by electrospray ionization mass spectrometry
- Author
-
Kunio Gonmori, Kayoko Minakata, Hideki Nozawa, Masako Suzuki, Kanako Watanabe, and Osamu Suzuki
- Subjects
Cisplatin ,Chromatography ,Electrospray ionization ,Biochemistry (medical) ,Oxalic acid ,chemistry.chemical_element ,Toxicology ,Isoamyl alcohol ,Mass spectrometry ,Direct flow ,Pathology and Forensic Medicine ,Malignant lymphoma ,chemistry.chemical_compound ,chemistry ,medicine ,Platinum ,medicine.drug - Abstract
Platinum (Pt) levels were determined in various tissues and body fluids obtained from a patient who died 181 days after cisplatin overdosing. The symptoms of cisplatin overdose, however, might have almost disappeared by day 40, and the patient’s death was ascribed to the recurrence of malignant lymphoma. Determination of Pt derived from cisplatin was performed by electrospray ionization mass spectrometry (ESI-MS) using silver (Ag) as internal standard. Pt and Ag complexed with diethyldithiocarbamate (DDC) in wetashed blood, and tissue solutions were extracted into isoamyl alcohol, and then acidified with oxalic acid. By injecting an aliquot of the isoamyl alcohol layer into a mass spectrometer in the direct flow injection mode, the quantitation was performed using the signals of Pt(DDC)3 + and Ag(DDC)2 + at m/z 639 and 403, respectively. The Pt levels ranged from 25ng/ml in blood to 2050ng/g wet weight in the liver of the patient, indicating that Pt remained at high levels in tissues, even after a period as long as 181 days after cisplatin overdosing.
- Published
- 2006
41. Rapid and sensitive identification and determination of Urine Luck by ESI-MS after reduction of chromate
- Author
-
Hideki Nozawa, Osamu Suzuki, Kunio Gonmori, Naoko Okamoto, Kayoko Minakata, and Kanako Watanabe
- Subjects
Detection limit ,Chromatography ,Chemistry ,Electrospray ionization ,Biochemistry (medical) ,Pyridinium chlorochromate ,Urine ,Toxicology ,Mass spectrometry ,Mass chromatogram ,Isoamyl alcohol ,Pathology and Forensic Medicine ,chemistry.chemical_compound ,bacteria ,Selected ion monitoring - Abstract
Urine Luck, the main component of which is pyridinium chlorochromate (PCC), is a popular adulterant used to conceal drugs present in urine samples. Electrospray ionization mass spectrometry with direct flow injection was employed to identify and quantitate PCC after complex formation of chromium (Cr6+) in PCC with diethyldithiocarbamate and its extraction with isoamyl alcohol. The quantitation was performed by selected ion monitoring at m/z 513, and the detection limit was 20 pg PCC (equivalent to 5pg Cr6+) in 1 µl of an injected volume. The integrated area of the mass chromatogram was proportional to the amount up to 2000 pg PCC with the limit of quantitation of 60 pg PCC in an injected volume. The recoveries of PCC from 50µl of urine spiked at 10−7 and 10−6M were 93% and 95%, respectively. The present method for analysis of Urine Luck is recommended for use in forensic analysis because of its speed, high sensitivity, and high specificity.
- Published
- 2006
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