研究者業績

井上 博之

イノウエ ヒロユキ  (Hiroyuki Inoue)

基本情報

所属
千葉大学 大学院医学研究院 特任教授
学位
医学博士(名古屋市立大学)

J-GLOBAL ID
200901079950806269
researchmap会員ID
5000005156

受賞

 1

論文

 164
  • Kenji Kuwayama, Kenji Tsujikawa, Hajime Miyaguchi, Tatsuyuki Kanamori, Yuko T. Iwata, Hiroyuki Inoue
    ANALYTICAL AND BIOANALYTICAL CHEMISTRY 405(12) 3945-3952 2013年5月  査読有り
    The aim of this study was to determine whether an ingested drug and its metabolites could be detected in the subject's fingerprints. Caffeine (CF) was chosen as the model drug. Three healthy subjects were asked to consume a cup of coffee (ca. 100 mL) containing 80 micro micro mg CF as the total dose, which is the normal amount in one cup of coffee. After washing hands with water to remove external contaminants, each subject pressed the index fingertip to a collecting matrix just before consuming the test cup of coffee, and then again pressed the index fingertip to the collecting matrix after 1, 3, 5, and 7 h. The time curve of the amounts of CF and its metabolites-theobromine (TB), paraxanthine (PX), and theophylline (TP)-in fingerprints and blood was determined using liquid chromatography/tandem mass spectrometry (LC/MS). A filter paper wetted with water (50 mu L) was an efficient collecting matrix for extracting the analytes from the fingertip. With optimized sample preparation and LC/MS conditions, the total operating time, from taking the fingerprints to obtaining the analytical result, was approximately 10 min. The lower limits of quantification for CF, TB, PX, and TP were 0.5, 5, 0.5, and 5 ng/fingerprint, respectively. The amount of CF or PX determined in fingerprints obtained over 7 h after coffee intake was significantly greater than the amount determined in fingerprints taken before drinking coffee. Fingerprints were a more efficient source for drug testing than other biological samples, such as blood and sweat, because the procedures for sampling and extracting the drugs were simpler and took less time. The method could be used to prove drug intake in criminal investigations.
  • Kenji Tsujikawa, Kenji Kuwayama, Hajime Miyaguchi, Tatsuyuki Kanamori, Yuko T. Iwata, Hiroyuki Inoue
    Forensic Science International 227(1-3) 42-44 2013年4月10日  査読有り
    We report a case of seized crystalline methamphetamine (MA) samples showing unique drug profiles. The samples were mainly composed of (S)-(+)-MA, with each containing a slight amount of (R)-(-)-MA (enantiomeric excess: 99.2-99.4%). 1-Phenyl-2-propanol and N-methyl-2-phenylacetamide were detected as characteristic impurities. These analytical results suggested that the samples were synthesized as racemic MA by reductive amination of 1-phenyl-2-propanone, which was synthesized from phenylacetic acid, putatively prepared from phenylacetic acid ester, and then the racemic MA was optically resolved to the (+)-form-rich product. This proposed preparation route was in accordance with recent reports of seizures worldwide of the raw materials of MA such as phenylacetic acid derivatives, methylamine, and tartaric acid (optical resolving reagent). © 2012 Elsevier Ireland Ltd.
  • Yuko T. Iwata, Toshiyasu Mikuma, Kenji Kuwayama, Kenji Tsujikawa, Hajime Miyaguchi, Tatsuyuki Kanamori, Hiroyuki Inoue
    Forensic Science International 226(1-3) 235-239 2013年3月10日  査読有り
    We examined the applicability of chemically modified capillaries on the chiral capillary electrophoresis of essential compounds for methamphetamine (MA) profiling (MA, amphetamine, ephedrine, pseudoephedrine, norephedrine, and norpseudoephedrine) using highly sulfated γ-cyclodextrin as a chiral selector. Four types of chemically modified capillaries, namely, FunCap-CE/Type D (possessing diol groups), Type A (amino groups), Type C (carboxyl groups), and Type S (sulfate groups), were evaluated. Repeatability, speed, and good chiral resolution sufficient for routine MA profiling were achieved with the Type S capillary. © 2013 Elsevier Ireland Ltd.
  • 桑山健次, 辻川健治, 金森達之, 岩田祐子, 井上博之
    法科学技術 18 143-153 2013年  査読有り
  • 桑山健次, 辻川健治, 金森達之, 岩田祐子, 井上博之
    法科学技術 18 135-141 2013年  査読有り
  • Tatsuyuki Kanamori, Kyoko Nagasawa, Kenji Kuwayama, Kenji Tsujikawa, Yuko T. Iwata, Hiroyuki Inoue
    Journal of Forensic Sciences 58(1) 279-287 2013年1月  査読有り
    The metabolites of 4-bromo-2,5-dimethoxyphenethylamine (2C-B), a psychoactive drug with hallucinogenic activity, were investigated in a urine sample from a user of 2C-B. The urine sample was deconjugated enzymatically and the metabolites were recovered by liquid-liquid extraction. The extract was analyzed by gas chromatography/mass spectrometry after derivatization, and the results were used to identify and quantitate the metabolites. 4-Bromo-2,5-dimethoxyphenylacetic acid was the most abundant metabolite of 2C-B in human urine and accounted for 73% of the total amount of detected metabolites, followed by 4-bromo-2-hydroxy-5-methoxyphenylacetic acid (13%) and 4-bromo-2,5-dimethoxyphenylethyl alcohol (4.5%). According to the literature, the main metabolites of 2C-B in rat urine are N-(4-bromo-2-methoxy-5-hydroxyphenylethyl)acetamide and N-(4-bromo-2-hydroxy-5-methoxyphenylethyl)acetamide. However, these metabolites accounted for only a small proportion of the total amount of detected metabolites in human urine, which indicates that there are significant species-specific differences in the metabolism of 2C-B. 4-Bromo-2,5-dimethoxyphenylacetic acid, which was the most abundant metabolite in human urine, is thought to be generated by deamination of 2C-B by monoamine oxidase (MAO) followed by oxidation by aldehyde dehydrogenase. Our results suggest that MAO plays a crucial role in the metabolism of 2C-B in humans. © 2012 American Academy of Forensic Sciences.
  • Kenji Kuwayama, Kenji Tsujikawa, Hajime Miyaguchi, Tatsuyuki Kanamori, Yuko T. Iwata, Hiroyuki Inoue
    ANALYTICAL AND BIOANALYTICAL CHEMISTRY 404(6-7) 1823-1830 2012年10月  査読有り
    Matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI/IMS) is a useful tool for measuring drug distributions. To obtain reproducible analytical results with MALDI/IMS, it is essential to apply a homogeneous matrix coating onto sample surfaces. A simple and inexpensive automatic matrix spraying system (AMSS) with good reproducibility was developed in this study. In addition, drug distributions in organs were measured by MALDI/IMS using the AMSS for forensic toxicology applications. The AMSS was constructed from simple components, including an air brush, a turntable, and a microscope. Organ slices placed onto conductive sheets were attached to the turntable. The trigger of the air brush was held with a clamp to ensure that it sprayed continuously onto a defined area of the table. Periodic spraying of the matrix solution and evaporation of solvent were performed by rotating the turntable. The droplets and crystals on the sample surfaces were observed under a microscope attached to the turntable. The droplet size, rotation rate of the turntable, and the formulation of the matrix solution were optimized. The homogeneity of the matrix coating was evaluated using the coefficients of variation (CV) obtained by quantifying the color density of the sheet surface. The AMSS enabled more homogeneous matrix coating (intersheet CV = 5.4 %) than manual spraying (intersheet CV = 16.7 %) when 10 mL of 0.5 % aqueous trifluoroacetic acid/acetonitrile (1:3, v/v) containing 10 mg/mL alpha-cyano-4-hydroxycinnamic acid were sprayed as droplets less than 50 mu m in diameter onto a turntable rotating at 30 rpm. The distributions of 3,4-methylenedioxymethamphetamine (MDMA) and its main metabolites in the brain, liver, and kidney of a mouse that died from an MDMA overdose (58 mg/kg i.p.) were visualized by MALDI/IMS using the AMSS. The ion intensities of MDMA obtained from the same regions on three sequential kidney slices showed acceptable variations (CV = 2.9-8.8 % for five different regions), implying repeatable measurements with MALDI/IMS using the AMSS. It was revealed that MDMA was particularly concentrated around the brain stem and the major calix of the kidney. The AMSS would be suitable for preparing samples for measuring the distributions of drugs in organs at toxic dose levels in forensic toxicological applications.
  • Kenji Tsujikawa, Toshiyasu Mikuma, Kenji Kuwayama, Hajime Miyaguchi, Tatsuyuki Kanamori, Yuko T. Iwata, Hiroyuki Inoue
    FORENSIC SCIENCE INTERNATIONAL 220(1-3) 103-110 2012年7月  査読有り
    Analogs of methcathinone (MC), a psychoactive stimulant, are in circulation all over the world. These analogs have been assumed to be unstable in alkaline solutions, as is MC itself. The aims of this study were: (i) to identify the degradation products of 4-methylmethcathinone (4-MMC), a typical MC analog, in solution at pH 12 and to determine the degradation pathway, (ii) to investigate the effects of antioxidants such as L-ascorbic acid and sodium sulfite on the degradation of 4-MMC, and (iii) to investigate the stability of seven MC analogs (4-MMC, 4-, 3-, or 2-fluoromethcathinone, 4-methoxymethcathinone, N-ethylcathinone, and N,N-dimethylcathinone) in solutions at different pHs.1-(4-Methylphenyl)-1,2-propanedione (MPPD), 4-methylbenzoic acid (MBA), N,4-dimethylbenzamide (DMBA), and N-acetyl-4-MMC (N-Ac-4-MMC) were identified as the degradation products of 4-MMC in pH 12 solution by gas chromatography-mass spectrometry. There are two degradation pathways for 4- MMC as follows: (a) 4-MMC -> MPPD -> MBA -> DMBA and (b) 4-MMC -> N-Ac-4-MMC. Oxidants such as dissolved oxygen were presumed to be involved in this degradation based on the suppressive effects generated by the addition of antioxidants. All of the seven MC analogs tested were stable in acidic (pH 4) solution but degraded in neutral-to-basic solutions. Their degradation rates increased with increasing pH, and varied with their chemical structures. These findings will be very useful for not only forensic analysis but also future pharmacokinetic analysis. (c) 2012 Elsevier Ireland Ltd. All rights reserved.
  • Kenji Kuwayama, Kenji Tsujikawa, Hajime Miyaguchi, Tatsuyuki Kanamori, Yuko T. Iwata, Hiroyuki Inoue
    JOURNAL OF FORENSIC SCIENCES 57(4) 1008-1013 2012年7月  査読有り
    Illicit amphetamine-type stimulant (ATS) tablets commonly contain one or more active ingredients, which have hallucinogenic and/or stimulant effects. Because components such as 3,4-methylenedioxymethamphetamine (MDMA) and methamphetamine (MA) in ATS tablets have similar chemical structures, they could be metabolized by common metabolic enzymes. To investigate potential metabolic interactions of ATS tablet components, we studied the in vitro metabolism of MDMA and MA using human metabolic enzymes. MDMA and MA were mainly metabolized by cytochrome P450 2D6 (CYP2D6) and mutually inhibited the production of their main metabolites. In vivo experiments were also performed using intravenous administration of MDMA, MA, or their mixture to rats. The plasma concentrations of MDMA and MA after co-administration were higher than those after administration of MDMA or MA alone. The results in this study imply that multiple components in ATS tablets can interact to mutually inhibit their metabolism and potentially enhance the toxicity of each component.
  • Lee, J, Park, Y, Yang, W, Chung, H, Choi W, Inoue, H, Kuwayama, K, Park, J
    Forensic Sci. Int. 215(1-3) 175-178 2012年2月  査読有り
  • 宮口 一, 杉山 茂, 樋口 美代子, 柳堀 あや子, 宮川 治彦, 井上 博之
    日本法科学技術学会誌 17(1) 27-34 2012年  
    A standard autoinjector (Shimadzu AOC-20i) was upgraded with a dedicated program and applied for the automatic operation of micro extraction by packed sorbent (MEPS) instead of an expensive multipurpose autosampler to carry out a confirmation analysis of methamphetamine, amphetamine, 3,4-methylenedioxymethamphetamine and 3,4-methylenedioxyamphetamine in hair by gas chromatography/mass spectrometry. Specification of the inlet liner, which is important for large volume injection utilizing programmable temperature vaporization (PTV), was studied, and lifetime of the liner was evaluated by repetitive analyses. By utilizing this system, full-scan electron-ionization mass spectra that were identical to the authentic acetylated analytes were observed using 3 mg of a fortified hair sample at 0.20 ng mg−1, which was more sensitive than the previous system. Although the lifetime of the inlet liner was relatively short (12-13 times use), this system is beneficial for the confirmation analysis of amphetamine-type stimulants in hair.<br>
  • Kenji Kuwayama, Kenji Tsujikawa, Hajime Miyaguchi, Tatsuyuki Kanamori, Yuko T. Iwata, Hiroyuki Inoue
    ANALYTICAL AND BIOANALYTICAL CHEMISTRY 402(3) 1257-1267 2012年1月  査読有り
    Rapid and precise identification of toxic substances is necessary for urgent diagnosis and treatment of poisoning cases and for establishing the cause of death in postmortem examinations. However, identification of compounds in biological samples using gas chromatography and liquid chromatography coupled with mass spectrometry entails time-consuming and labor-intensive sample preparations. In this study, we examined a simple preparation and highly sensitive analysis of drugs in biological samples such as urine, plasma, and organs using thin-layer chromatography coupled with matrix-assisted laser desorption/ionization mass spectrometry (TLC/MALDI/MS). When the urine containing 3,4-methylenedioxymethamphetamine (MDMA) without sample dilution was spotted on a thin-layer chromatography (TLC) plate and was analyzed by TLC/MALDI/MS, the detection limit of the MDMA spot was 0.05 ng/spot. The value was the same as that in aqueous solution spotted on a stainless steel plate. All the 11 psychotropic compounds tested (MDMA, 4-hydroxy-3-methoxymethamphetamine, 3,4-methylenedioxyamphetamine, methamphetamine, p-hydroxymethamphetamine, amphetamine, ketamine, caffeine, chlorpromazine, triazolam, and morphine) on a TLC plate were detected at levels of 0.05 -aEuro parts per thousand 5 ng, and the type (layer thickness and fluorescence) of TLC plate did not affect detection sensitivity. In addition, when rat liver homogenate obtained after MDMA administration (10 mg/kg) was spotted on a TLC plate, MDMA and its main metabolites were identified using TLC/MALDI/MS, and the spots on a TLC plate were visualized by MALDI/imaging MS. The total analytical time from spotting of intact biological samples to the output of analytical results was within 30 min. TLC/MALDI/MS enabled rapid, simple, and highly sensitive analysis of drugs from intact biological samples and crude extracts. Accordingly, this method could be applied to rapid drug screening and precise identification of toxic substances in poisoning cases and postmortem examinations.
  • Kenji Tsujikawa, Toshiyasu Mikuma, Kenji Kuwayama, Hajime Miyaguchi, Tatsuyuki Kanamori, Yuko T. Iwata, Hiroyuki Inoue
    FORENSIC TOXICOLOGY 30(1) 70-75 2012年1月  査読有り
    We report a case of seized methamphetamine (MA) samples showing unique drug profiles. Conventional drug profiling such as impurity profiling and chiral analysis as well as stable isotope ratio mass spectrometry (IRMS) was performed on seven MA-HCl samples. The results of impurity profiling suggested that the samples were synthesized by reductive amination. The high enantiomeric purities of the samples suggested that the samples were optically resolved. The delta C-13 and delta N-15 values gave different grouping patterns from conventional drug profiling. This is the first case report of the use of IRMS with seized MA samples presumptively synthesized by reductive amination.
  • Kenji Kuwayama, Kenji Tsujikawa, Hajime Miyaguchi, Tatsuyuki Kanamori, Yuko T. Iwata, Hiroyuki Inoue
    RAPID COMMUNICATIONS IN MASS SPECTROMETRY 25(17) 2397-2406 2011年9月  査読有り
    Amphetamine-type stimulants (ATS) such as methamphetamine are widely abused and can cause toxic effects in the body. In this study, a simple and accurate analytical method for distribution measurement of drugs in organs was developed to visualize localization of ATS in organs and to complement drug distribution by mass spectrometry imaging (MSI). The brain, liver and kidney from rats to which ATS had been administered were segmented into blocks of 2 x 2 x 2 mm(3) at -30 degrees C. Each organ block was micropulverized with a stainless-steel bullet at -80 degrees C. The concentrations of drugs in each block were measured by liquid chromatography/tandem mass spectrometry. The three-dimensional distribution of drugs in a whole organ was expressed using color gradation of drug concentration after reconstruction of all blocks to the original locations. The distribution was also compared with that obtained by MSI. This method enabled measurement of drug distribution in organs with simple and clean procedures and accurate quantification unlike autoradiography and MSI. The methamphetamine concentrations were different between parts in an organ, particularly in the kidney. This method could be applicable to the measurement of the distribution of compounds in various solid samples and could be used as a complementary method for the measurement of the distribution of compounds by MSI. Copyright (C) 2011 John Wiley & Sons, Ltd.
  • Tatsuyuki Kanamori, Kenji Kuwayama, Kenji Tsujikawa, Hajime Miyaguchi, Yuko T. Iwata, Hiroyuki Inoue
    JOURNAL OF FORENSIC SCIENCES 56(5) 1319-1323 2011年9月  査読有り
    This article describes the synthesis and identification of urinary metabolites of 4-iodo-2,5-dimethoxyphenethylamine (2C-I), a new psychoactive drug. 2C-I hydrochloride was administered orally to male Sprague-Dawley rats, and the urinary extracts were analyzed by gas chromatography/mass spectrometry (GC/MS), then five putative 2C-I metabolites were synthesized in our laboratory. In the synthetic process of the 2C-I metabolites, iodination of the aromatic ring was successfully carried out using iodine and orthoperiodic acid as the iodination reagent, and selective debenzylation of aryl benzyl ether was accomplished by the acid hydrolysis method using trifluoroacetic acid and thioanisole. The synthesized metabolites were well separated and detected by GC/MS after valeryl derivatization. The results showed that 2C-I underwent O-demethylation, N-acetylation, and deamination, followed by oxidation to the corresponding carboxylic acid in rats. The data presented in this study will be very useful for the analysis of 2C-I and its metabolites in forensic samples.
  • Tatsuyuki Kanamori, Kenji Kuwayama, Kenji Tsujikawa, Hajime Miyaguchi, Yuko Togawa-Iwata, Hiroyuki Inoue
    FORENSIC TOXICOLOGY 29(2) 142-151 2011年7月  査読有り
    The in vitro metabolisms of 4-bromo-2,5-dimethoxyphenethylamine (2C-B), 5-methoxy-N,N-diisopropyltryptamine (5-MeO-DIPT), and 2,5-dimethoxy-4-propylthiophenethylamine (2C-T-7) were studied using TESTLIVER (TM)-rat and TESTLIVER (TM)-human, which are new three-dimensional rat and human hepatocyte culture systems, respectively. The metabolites produced in the incubation media were measured by liquid chromatography-tandem mass spectrometry or gas chromatography-mass spectrometry. The data obtained with the in vitro system of rat origin were carefully compared with those obtained by rat in vivo experiments; most of the metabolites found in the in vivo experiments could be reproduced in the present three-dimensional in vitro experiments, although quantitative metabolite distribution patterns obtained with the three-dimensional system was somewhat different from those of in vivo experiments. Because human in vivo experiments are not possible, especially for dubious designer drugs, the in vitro experiments using the three-dimensional human hepatocyte culture system seem very useful for studying human metabolism of new designer drugs as an alternative to human experiments.
  • Kenji Tsujikawa, Toshiyasu Mikuma, Kenji Kuwayama, Hajime Miyaguchi, Tatsuyuki Kanamori, Yuko T. Iwata, Hiroyuki Inoue
    XENOBIOTICA 41(7) 578-584 2011年7月  査読有り
    N-hydroxy-3,4-methylenedioxymethamphetamine (N-OH-MDMA) is a psychedelic illicit drug that has recently been circulating in Japan. The aims of this study were (i) to optimise enzymatic hydrolysis conditions of the conjugated forms of N-OH-MDMA and its demethylated metabolite N-hydroxy-3,4-methylenedioxyamphetamine (N-OH-MDA), (ii) to investigate the urinary excretion profiles of N-OH-MDMA in rats, and (iii) to compare urinary excretion profiles of N-OH-MDMA and 3,4-methylenedioxymethamphetamine (MDMA). Conjugated forms of the N-hydroxylated compounds (N-OH-MDMA and N-OH-MDA) were almost successfully hydrolysed to their nonconjugated forms under anaerobic conditions after helium purging of the solution. The sum of N-OH-MDMA and N-OH-MDA was used to evaluate the amount of excreted N-hydroxylated metabolites because of degradation of N-OH-MDMA to N-OH-MDA during hydrolysis. Up to 24 h after oral administration of N-OH-MDMA oxalate, the main urinary metabolites were MDMA (14.3% of dose) and 3,4-MDA (7.7% of dose). Most of the N-hydroxylated forms were excreted as glucuronide conjugates. The total amount of N-hydroxylated metabolites after hydrolysis was 1.1% of dose. Urinary excretion profiles of MDMA were similar to that of N-OH-MDMA. It may be difficult to differentiate between abuse of MDMA and N-OH-MDMA by urine analysis.
  • Fumiyo Kasuya, Yasushi Miwa, Maya Kazumi, Hiroyuki Inoue, Hiroyuki Ohta
    INTERNATIONAL JOURNAL OF TOXICOLOGY 30(3) 367-376 2011年5月  査読有り
    Multiple changes in metabolic levels could be useful for understanding physiological toxicity. To explore further risk factors for the convulsions induced by the interaction of nonsteroidal anti-inflammatory and new quinolone antimicrobial drugs, the effect of sparfloxacin, enoxacin, and felbinac on fatty acid metabolism and glucose concentrations in the liver, brain, and blood of rats was investigated. The levels of long-chain acyl-CoAs (C18:1 and C20:4) in the liver and brain were decreased at the onset of convulsions induced by the coadministration of enoxacin with felbinac. Then, glucose concentrations in the liver and blood were decreased, whereas they were increased in a dose-dependant manner in the brain. However, the formation of acyl-CoAs and glucose levels in the liver, brain, and blood was not significantly influenced by enoxacin, felbinac, and sparfloxacin alone, respectively. The disturbance of both fatty acid metabolism and glucose levels might be associated with the increased susceptibility to convulsions, which may contribute to further understanding of the toxic effects associated with these drugs.
  • Hajime Miyaguchi, Hiroyuki Inoue
    ANALYST 136(17) 3503-3511 2011年  査読有り
    An LTQ Orbitrap XL hybrid mass spectrometry method was developed for the determination of illicit drugs and their metabolites, including amphetamine (AP), methamphetamine (MA), dimethylamphetamine (DMA), 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA), ketamine (KET), norketamine (NK), cocaine (COC) and benzoylecgonine (BE), in hair. Micropulverized extraction was employed for sample preparation using a small hair sample (2 cm piece or 0.2 mg). Recoveries of the analytes during sample preparation were estimated using fortified hair samples and ranged from 35.5% for COC to 71.7% for AP. High resolution full-scan mass spectra and unit resolution product-ion spectra were obtained with the Orbitrap analyzer and the linear ion-trap analyzer, respectively. High-resolution extracted ion chromatograms at a tolerance of 3 ppm were utilized for quantification. The analytes were identified using the product-ion spectra in combination with the accurate masses of the corresponding protonated molecules observed in the high-resolution mass spectra. Lower limits of quantification obtained from a 0.2 mg hair sample were 0.050 ng mg(-1) (MDMA, KET and BE), 0.10 ng mg(-1) (AP, MA, DMA, NK and COC) and 0.50 ng mg(-1) (MDA). Two reference materials were analyzed for verification, and segmental analysis of single strands of hair specimens from actual cases was performed.
  • Yuko T. Iwata, Kenji Kuwayama, Kenji Tsujikawa, Hajime Miyaguchi, Tatsuyuki Kanamori, Hiroyuki Inoue
    FORENSIC TOXICOLOGY 28(2) 119-123 2010年7月  査読有り
    We report a case of seized methamphetamine (MA) samples showing unique profiles of stable isotopic compositions. Three packages of MA-HCl samples seized simultaneously from one suspect were subjected to gas chromatographic impurity profiling and stable isotope ratio mass spectrometry (IRMS). The samples showed similar impurity profiles by gas chromatography, but their stable isotopic compositions were complicated. The delta(15)N values of the samples from each package varied widely when the crystals were analyzed separately; we could differentiate two major groups labeled I and II, and also their subgroups. Each of the three packages contained MA-HCl crystals belonging to multiple groups and subgroups. It was considered that several batches of MA-HCl with starting materials from different sources were mixed together after a similar or the same synthesis procedure and then divided into the packages. This is the first report to show that stable IRMS is useful for differentiating seized MA using small crystals from different sources.
  • Kenji Tsujikawa, Kenji Kuwayama, Hajime Miyaguchi, Tatsuyuki Kanamori, Yuko T. Iwata, Hiroyuki Inoue
    FORENSIC TOXICOLOGY 28(1) 55-57 2010年1月  査読有り
  • Kenji Tsujikawa, Kenji Kuwayama, Hajime Miyaguchi, Tatsuyuki Kanamori, Yuko T. Iwata, Hiroyuki Inoue
    FORENSIC SCIENCE INTERNATIONAL 193(1-3) 106-111 2009年12月  査読有り
    N-Hydroxy-3,4-methylenedioxymethamphetamine (N-OH-MDMA) is a lesser known psychedelic drug that has recently circulated in the Japanese illicit drug market. From the instability of the similarly structured N-hydroxy-3,4-methylenedioxyamphetamine (N-OH-MDA) in neutral-to-basic aqueous solution, it was presumed that N-OH-MDMA would also degrade in aqueous solution. The aims of this study were: (i) investigation of the degradation of N-OH-MDMA in aqueous solution and its prevention, (ii) identification of the degradation products, (iii) determination of the pKa for the conjugate acid of NOH-MDMA, and (iv) evaluation of liquid-liquid extraction recovery. N-OH-MDA was also included in some of these studies. N-OH-MDMA degraded to 14.9% of initial concentration after 2 h storage in pH 10 buffer solution at 22 degrees C. This degradation was completely inhibited at least for 2 h by addition of L-ascorbic acid, a strong reactive oxygen scavenger. These findings indicate that reactive oxygen species in alkaline solution were involved in N-OH-MDMA degradation. N-OH-MDA, alpha-methyl-(N-methylene)-3&apos;,4&apos;-methylenedioxybenzeneethanamine and 3&apos;,4&apos;-methylenedioxyphenyl-2-propanone oxime were found as degradation products of N-OH-MDMA in alkaline solution. The pKa for the conjugate acid of N-OH-MDMA was determined by titration to be 5.52, which was much lower than that reported for 3,4-methylenedioxymethamphetamine (pKa = 10.38). Excellent recoveries for N-OH-MDMA and N-OH-MDA (&gt;98%) were achieved by extraction with ethyl acetate or chloroform from a basic buffer ( pH 10) solution containing 0.1% L-ascorbic acid. (C) 2009 Elsevier Ireland Ltd. All rights reserved.
  • Hiroyuki Inoue, Hiroaki Hashimoto, Susumu Watanabe, Yuko T. Iwata, Tatsuyuki Kanamori, Hajime Miyaguchi, Kenji Tsujikawa, Kenji Kuwayama, Noriyuki Tachi, Naohito Uetake
    JOURNAL OF MASS SPECTROMETRY 44(9) 1300-1307 2009年9月  査読有り
    A novel approach to the analysis of ecstasy tablets by direct mass spectrometry coupled with thermal desorption (TD) and counter-flow introduction atmospheric pressure chemical ionization (CFI-APCI) is described. Analytes were thermally desorbed with a metal block heater and introduced to a CFI-APCI source with ambient air by a diaphragm pump. Water in the air was sufficient to act as the reactive reagent responsible for the generation of ions in the positive corona discharge. TD-CFI-APCI required neither a nebulizing gas nor solvent flow and the accompanying laborious optimizations. Ions generated were sent in the direction opposite to the air flow by an electric field and introduced into an ion trap mass spectrometer. The major ions corresponding to the protonated molecules ([M + H](+)) were observed with several fragment ions in full scan mass spectrometry (MS) mode. Collision-induced dissociation of protonated molecules gave characteristic product-ion mass spectra and provided identification of the analytes within 5 s. The method required neither sample pretreatment nor a chromatographic separation step. The effectiveness of the combination of TD and CFI-APCI was demonstrated by application to the direct mass spectrometric analysis of ecstasy tablets and legal pharmaceutical products. Copyright (C) 2009 John Wiley & Sons, Ltd.
  • Kenji Kuwayama, Kenji Tsujikawa, Hajime Miyaguchi, Tatsuyuki Kanamori, Yuko T. Iwata, Hiroyuki Inoue
    JOURNAL OF ANALYTICAL TOXICOLOGY 33(5) 266-271 2009年6月  査読有り
  • Hajime Miyaguchi, Yuko T. Iwata, Tatsuyuki Kanamori, Kenji Tsujikawa, Kenji Kuwayama, Hiroyuki Inoue
    JOURNAL OF CHROMATOGRAPHY A 1216(18) 4063-4070 2009年5月  査読有り
    We developed a rapid identification and quantification method for the toxicological analysis of methamphetamine and amphetamine in human hair by gas chromatography/mass spectrometry coupled with a novel combination of micropulverized extraction, aqueous acetylation and microextraction by packed sorbent (MEPS) named MiAMi-GC/MS. A washed hair sample (1-5 mg) was micropulverized for 5 min in a 2 mL plastic tube with 250 mu L of water. An anion-exchange sorbent was added to adsorb anionic interferences. After removing the residue with a membrane-filter unit, sodium carbonate and acetic anhydride was admixed in turn. Acetylation was completed in approximately 20 min at room temperature. The acetylated analytes in the reaction liquid were concentrated to an octadecylsilica sorbent packed in the needle of a syringe by a CombiPAL autosampler. Elution was carried out with 50 mu L of methanol, and the entire eluate injected into a gas chromatograph using a programmable temperature vaporizing (PTV) technique. The time required for sample preparation and GC/MS analysis was approximately 1 h from a washed hair sample, and an evaporation process was not required. Ranges for quantification were 0.20-50 (ng/mg) each for methamphetamine and amphetamine using 1 mg of hair. Accuracy and relative standard deviation (RSD) were evaluated intraday and interday at three concentrations, and the results were within the limit of a guidance issued by U.S. Food and Drug Administration. For identification, full-scan mass spectra of methamphetamine and amphetamine were obtained using 5 mg of fortified hair samples at 0.2 ng/mg. The extraction device of MEPS was durable for at least 300 extractions, whereas the liner of the gas chromatograph should be replaced after 20-30 times use. The carry over was estimated to be about 1-2%. This sample-preparation method coupled with CC/MS is fast and labor-saving in comparison with conventional methods. (C) 2009 Elsevier B.V. All rights reserved.
  • K. Tsujikawa, K. Kuwayama, H. Miyaguchi, T. Kanamori, Y. T. Iwata, H. Inoue
    XENOBIOTICA 39(5) 391-398 2009年  査読有り
    Salvinorin A is the main active psychoactive ingredient in Salvia divinorum, a Mexican plant that has been widely available as a hallucinogen in recent years. The aims of this study were to investigate the stability of salvinorin A in rat plasma, esterases responsible for its degradation, and estimation of the degradation products. The apparent first-order rate constants of salvinorin A at 37C, 25C, and 4C were 3.8 10-1, 1.1 10-1, and 6.0 10-3 h-1, respectively. Salvinorin A degradation was markedly inhibited by the addition of sodium fluoride, an esterase inhibitor. Moreover, phenylmethylsulfonyl fluoride (serine esterase inhibitor) and bis-p-nitrophenyl phosphate (carboxylesterase inhibitor) also inhibited salvinorin A degradation. In contrast, little or no suppression of the degradation was seen with 5,5-dithiobis-2-nitrobenzoic acid (arylesterase inhibitor), ethopropazine (butyrylcholinesterase inhibitor), and BW284c51 (acetylcholineseterase inhibitor). These findings indicated that carboxylesterase was mainly involved in the salvinorin A hydrolysis in rat plasma. The degradation products of salvinorin A estimated by liquid chromatography-mass spectrometry included the deacetylated form (salvinorin B) and the lactone-ring-open forms of salvinorin A and salvinorin B. This lactone-ring-opening reactions were involved in calcium-dependent lactonase.
  • Hajime Miyaguchi, Hiroko Takahashi, Toshinori Ohashi, Kazuma Mawatari, Yuko T. Iwata, Hiroyuki Inoue, Takehiko Kitamori
    FORENSIC SCIENCE INTERNATIONAL 184(1-3) 1-5 2009年1月  査読有り
    An automated full-range quantitation method for identifying d-methamphetamine in human hair using a microchip-based ELISA system (microELISA) in combination with a micropulverized extraction method for sample preparation has been developed. An antibody and a peroxidase-linked methamphetamine, both are commercially available, were used for the competitive ELISA assay. Method validation was carried Out using doped hair samples, and segmental analyses of real-case specimens were carried out by both microELISA and LC/MS/MS to verify the reliability and applicability of this new method. Due to the small size of the system and the lack of an evaporation process, sample preparation and quantitation can be accomplished easily and quickly (less than 30 min) in small-scale contamination-free environments. (c) 2008 Elsevier Ireland Ltd. All rights reserved.
  • Yuko T. Iwata, Kenji Kuwayama, Kenji Tsujikawa, Hajime Miyaguchi, Tatsuyuki Kanamori, Hiroyuki Inoue
    RAPID COMMUNICATIONS IN MASS SPECTROMETRY 22(23) 3816-3822 2008年12月  査読有り
    Drug profiling, extraction of physical and/or chemical profiles from abused drug samples, is useful for inferring and characterizing links between samples originating from the same and different seizures, and supports drug crime investigations. We describe an evaluation method for linking methamphetamine (MA) seizures using stable carbon and nitrogen isotopic compositions concurrently with gas chromatographic impurity profiling, which is one of the major methods of drug profiling. Several sets of MA seized in Japan, whose investigative information indicated linkages, were analyzed. The impurity profile of each set of seizures was quite similar and hierarchical cluster analysis showed a sample classification that was relatively consistent with the investigative information. The stable carbon and nitrogen isotopic compositions of the MA seizures varied between -29.40 and -24.90 (delta(13)C) and -2.29 and 5.94 (delta(15)N), respectively. In the delta(13)C-delta(15)N graph, MA seizures were classified into seven groups, probably reflecting different origins. The size of the cluster in the isotopic-composition graph was determined by pooled standard deviations (s(p)), the pooled estimates of measurement uncertainty. The sizes of the clusters were less than 6s(p) and the linkages between the MA seizures from the isotopic compositions were consistent with the impurity profiling and investigative information. The results showed that complementary use of stable-isotopic compositions with impurity profiling provides useful information for evaluating the links between seizures. Copyright (C) 2008 John Wiley & Sons, Ltd.
  • Chie Sato, Akibiro Furube, Ryuzi Katoh, Hidehiko Nonaka, Hiroyuki Inoue
    JAPANESE JOURNAL OF APPLIED PHYSICS 47(11) 8583-8589 2008年11月  査読有り
    We have tested the possibility of identifying illegal drugs by means of nanosecond transient absorption spectroscopy with a 10-ns UV-laser pulse for the excitation light and visible-to-near-IR light for the probe light. We measured the transient absorption spectra of acctonitrile solutions of d-methamphetamine, dl-3,4-methylenedioxymethamphetamine hydrochloride (MDMA). and dl-N-methyl-l-(1,3-benzodioxol-5-yl)-2-butanamine hydrochloride (MBDB), which are illegal drugs widely consumed in Japan. Transient absorption signals of these drugs were observed between 400 and 950 nm, a range in which they are transparent in the ground state. By analyzing the spectra in terms of exponential and Gaussian functions, we could identify the drugs and discriminate them from chemical subxtances have similar structures. We propose that transient absorption spectroscopy will be a useful, non-destructive method of inspecting for illegal drugs, especially when they are dissolved in liquids. Such amethod may even be used for drugs packed in opaque materials if it is further extended to utilize intense femtosecond laser pulses. [DOI: 10.1143/JJAP.47.8583]
  • Kenji Tsujikawa, Kenji Kuwayama, Hajime Miyaguchi, Tatsuyuki Kanamori, Yuko T. Iwata, Takemi Yoshida, Hiroyuki Inoue
    FORENSIC SCIENCE INTERNATIONAL 180(2-3) 105-109 2008年9月  査読有り
    Two major salvinorins, salvinorin A (SalA) and salvinorin B (SalB), in three Salvia divinorum dried leaf products and nine of its "concentrated extract" products circulated in Japan were determined. These ingredients were extracted twice with acetonitrile and decolored with graphite carbon powder. SalA and SalB were confirmed by liquid chromatography-tandem mass spectrometry in product ion scan mode, and quantified by high-performance liquid chromatography with UV detection (for SalA) and by mass spectrometry in single ion monitoring mode (for SalB). The SalA/SalB contents (mu g/mg) were in the range of 3.2-5.0/0.10-0.17 in the dried leaf products and 4.1-38.9/0.26-2.42 in the "concentrated extract" products. These findings would be useful for analysis of S. divinorum-related products circulated in the drug market. (C) 2008 Elsevier Ireland Ltd. All rights reserved.
  • Jae Sin Lee, Hee Sun Chung, Kenji Kuwayama, Hiroyuki Inoue, Mi Young Lee, Jeong Hill Park
    ANALYTICA CHIMICA ACTA 619(1) 20-25 2008年6月  査読有り
    Impurities produced during synthesis of methamphetamine (MA) show different patterns under various synthetic conditions. Valuable information on the origins and smuggling routes can be obtained by using impurities as chemical fingerprints. We have detected more than 100 compounds from 436 MA samples seized in Korea by gas chromatography-flame ionization detector and gas chromatography mass spectrometer, among which 31 impurities and three additives were identified. Twenty-six impurity peaks including unknowns were selected as the indicators of similarity, and were used as variables for cluster analysis. Cluster analysis result showed that part of the MA samples seized in Japan might have the same origin as those seized in Korea. It means that broad-based cooperation is necessary for efficient regulation of MA. Synthetic trends of the MA seizures of Korea were monitored by cluster analysis with 16 MA samples synthesized by three different methods in the previous work. We could find comparable changes of synthetic trends, which might have been influenced by domestic regulations and international situations. (C) 2008 Elsevier B.V. All rights reserved.
  • Hiroyuki Inoue, Kenji Kuwayama, Yuko T. Iwata, Tatsuyuki Kanamori, Kenji Tsujikawa, Hajime Miyaguchi
    FORENSIC TOXICOLOGY 26(1) 19-22 2008年6月  査読有り
    We present a method for simple and simultaneous determination of methamphetamine (MA) and dimethyl sulfone (DMS) in seized crystalline MA by fast gas chromatography with flame ionization detection. Samples dissolved in distilled water at 2 mg/ml were added to 80% potassium carbonate solution and extracted with dichloromethane/2-propanol (3 : 1) containing diphenylmethane as internal standard. The use of a narrow-bore capillary column gave fast and complete separation of three compounds within 1.3 min. The method was fully validated and applied to quantification of MA and DMS in MA hydrochloride crystal or powdered samples recently seized in Japan.
  • Kenji Kuwayama, Hiroyuki Inoue, Tatsuyuki Kanamori, Kenji Tsujikawa, Hajime Miyaguchi, Yuko T. Iwata, Seiji Miyauchi, Naoki Kamo
    JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES 867(1) 78-83 2008年5月  査読有り
    The aim of this work was to develop and validate a method for analysing amphetamine-type stimulants (ATSs) and their metabolites in plasma, urine and bile by liquid chromatography with a strong cation-exchange column-tandem mass spectrometry, and to apply it to the pharmacokinetic study of ATSs. 3,4-Methylenedioxymethamphetamine, methamphetamine, ketamine and their main metabolites, 4-hydroxy-3-methoxymethamphetamine, 3,4-methylenedioxyamphetamine, p-hydroxymethamphetamine, amphetamine and norketamine, were simultaneously quantified by the new method (50-5000 ng/ml). The coefficients of variation and the percent deviations for the eight compounds were in the range of 0.2 to 5.3% and -9.4 to +12.8%, respectively. The recoveries were over 90% in all biological samples tested. This method was effective for the separation and the identification of ATSs and their main metabolites having amine moieties in plasma, urine and bile, and was applicable to pharmacokinetic analysis of methamphetamine, ketamine and their main metabolites in biological samples. This analytical method should be useful for the pharmacokinetic analysis of ATSs. (C) 2008 Elsevier B.V. All rights reserved.
  • Kenji Kuwayama, Hiroyuki Inoue, Juthamard Phorachata, Kanyanan Kongpatnitiroj, Vichet Puthaviriyakorn, Kenji Tsujikawa, Hajime Miyaguchi, Tatsuyuki Kanamori, Yuko T. Iwata, Naoki Kamo, Tohru Kishi
    FORENSIC SCIENCE INTERNATIONAL 175(2-3) 85-92 2008年3月  査読有り
    Methamphetamine (MA) is one of the most frequently abused drugs worldwide. The aim of this study is to improve the analytical method for profiling MA impurity in order to compare and classify MA crystals seized in different countries and to investigate the relationships between seizures. To compare MA samples seized in Japan and Thailand, the following analytical method was adopted. A 50 mg sample of MA center dot HCl was dissolved in 1 ml of buffer solution (four parts 0.1 M phosphate buffer, pH 7.0, and one part 10% Na2CO3), impurities were extracted with 0.5 ml of ethyl acetate containing four internal standards (n-decane, n-pentadecane, n-eicosane and n-octacosane) and analyzed by gas chromatography with a flame ionization detector on a DB-5 capillary column (0.32 mm i.d. x 30 m, film thickness 1.0 mu m). Fourteen characteristic peaks oil chromatograms were selected for the comparison and classification of samples, and the data were evaluated by the Euclidean distance of the relative peak areas after logarithmic transformation. Sixty-nine samples seized in Japan and 42 seized in Thailand were analyzed. The samples were classified into four groups roughly by cluster analysis. In addition, when it was difficult to compare samples that had fewer impurities on chromatograms obtained from liquid-liquid extraction (LLE), solid-phase microextraction (SPME) was effective. Because many characteristic peaks were detected using SPME, SPME made it easy to compare samples of high purity. The combination of LLE and SPME was useful for impurity profiling of MA samples seized in different countries. (C) 2007 Elsevier Ireland Ltd. All rights reserved.
  • Kenji Tsujikawa, Kenji Kuwayama, Hajime Miyaquchi, Tatsuyuki Kanamori, Yuko T. Iwata, Takemi Yoshida, Hiroyuki Inoue
    ANALYTICA CHIMICA ACTA 608(1) 95-103 2008年2月  査読有り
    We tried to develop a library search system using a portable, attenuated total reflection Fourier transform infrared (ATR-FT-IR) spectrometer for on-site identification of 3,4-methylenedioxymethamphetamine (MDMA) and 3,4-methylenedioxyamphetamine (MDA) tablets. The library consisted of the spectra from mixtures of controlled drugs (e.g. MDMA and ketamine), adulterants (e.g. caffeine), and diluents (e.g. lactose). In the seven library search algorithms, the derivative correlation coefficient showed the best discriminant capability. This was enhanced by segmentation of the search area. The optimized search algorithm was validated by the positive (n = 154, e.g. the standard mixtures containing the controlled drug, and the MDMA/MDA tablets confiscated) and negative samples (n = 56, e.g. medicinal tablets). All validation samples except for four were judged truly. Final criteria for positive identification were decided on the basis of the results of the validation. In conclusion, a portable ATR-FT-IR spectrometer with our library search system would be a useful tool for on-site identification of amphetamine-type stimulant tablets. (c) 2007 Elsevier B.V All rights reserved.
  • Kanamori, T, Kuwayama, K, Tsujikawa, K, Miyaguchi, H, Iwata, Y.T, Inoue, H
    Xenobiotica 38(12) 1476-1486 2008年  査読有り
  • Inoue, H, Kanamori, T, Kuwayama, K, Iwata, Y.T, Satoh, T, Yanagihori, A, Matsushima, K
    Jpn. J. Forensic Sci. Tech. 13(1) 73-82 2008年  査読有り
    Sildenafil and related compounds, vardenafil, tadalafil and hydroxyhomosildenafil, in dietary supplements were characterized using thin layer chromatography (TLC), infrared (IR) spectroscopy, gas chromatography/mass spectrometry (GC/MS), high performance liquid chromatography (HPLC) and liquid chromatography/mass spectrometry (LC/MS). TLC with Dragendorff reagent gave a lower detection limit than 1 μg for all 4 compounds. IR spectra of the compounds were so characteristic as to discriminate one from another easily. After TMS derivatization, all the peaks of these compounds appeared and well-separated on the GC/MS chromatograms at a high column temperature (320°C), although hydroxyhomosildenafil was not detected without derivatization. In HPLC and LC/MS analyses, an ODS column with a mobile phase composed of a mixture of 20 mM ammonium acetate (pH 5.0) and methanol (40:60) allowed separation of the 4 compounds. Simple electrospray-ionization mass spectra with only protonated molecules were obtained except for tadalafil, which was cleaved easier than the other compounds, so cone voltage should be lower for tadalafil. Quantitative analysis of the 4 compounds was carried out using HPLC (UV at 230 nm). The lower limit of detection for each compound was 50 ng/ml at a 10-μl injection volume (0.5 ng on the column, S/N>3). A calibration curve was linear in the range of 0.01-1.0 mg/ml for each compound (r2>0.997). Our methods were applied to casework samples (confiscated tablets), and disclosed that those tablets contained varying amounts of sildenafil and/or tadalafil and were counterfeit products.<br>
  • Kenji Kuwayama, Hiroyuki Inoue, Tatsuyuki Kanamori, Kenji Tsujikawa, Hajime Miyaguchi, Yuko Iwata, Seiji Miyauchi, Naoki Kamo, Tohru Kishi
    BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 1778(1) 42-50 2008年1月  査読有り
    3,4-Methylenedioxymethamphetamine (MDMA) is an illegal amphetamine-type stimulant (ATS) that is abused orally in the form of tablets for recreational purposes. The aim of this work is to investigate the absorption mechanism of MDMA and other related compounds that often occur together in ATS tablets, and to determine whether such tablet components interact with each other in intestinal absorption. The characteristics of MDMA uptake by the human intestinal epithelial Caco-2 cell line were investigated. The Michaelis constant and the maximal uptake velocity at pH 6.0 were 1.11 mM and 13.79 nmol/min/mg protein, respectively, and the transport was electroneutral. The initial uptake rate was regulated by both intra- and extracellular pH. MDMA permeation from the apical to the basolateral side was inferior to that in the reverse direction, and a decrease in apical pH enhanced MDMA permeation from the basolateral to the apical side. These facts indicate that this transport system may be an antiporter of H.. However, under physiological conditions, the proton gradient cannot drive the MDMA uptake because it is inwardly directed. Large concentration differences of MDMA itself drive this antiporter. Various compounds with similar amine moieties inhibited the uptake, but substrates of organic cation transporters (OCT1-3) and an H+-coupled efflux antiporter, MATE, were not recognized. (c) 2007 Elsevier B.V. All rights reserved.
  • Kenji Tsujikawa, Kenji Kuwayama, Hajime Miyaguchi, Tatsuyuki Kanamori, Yuko Iwata, Hiroyuki Inoue, Tohru Kishi
    JOURNAL OF FORENSIC SCIENCES 53(1) 226-231 2008年1月  査読有り
    Cefoperazone and sublactam are prescribed in combination and used in the treatment of moderate to severe bacterial infections. Serious anaphylaxis is a rare side effect. This report describes a fatal case of suspected anaphylaxis after intravenous administration of a combination of the two drugs. Heart blood was analyzed for cefoperazone by protein precipitation with acetonitrile and by liquid-liquid precipitation for sublactam after protein precipitation with aqueous acetonitrile, followed by tandem mass spectrometry in the product ion scan mode for identification and by liquid chromatography mass spectrometry in the selected ion monitoring mode for quantitation. Calibration curves for cefoperazone and sublactam were linear over the range 0.07 to 1.93 and 0.046 to 0.914 mu g/ml respectively. The decedent's blood concentrations of cefoperazone and sublactam were 0.368 and 0.143 mu g/ml respectively. As these concentrations were below concentrations reported after single dosing studies and below those considered to be minimally inhibitory, death was presumed to have been caused by hypersensitivity and not an overdose. In conclusion, this procedure is useful for detecting and quantitating cefoperazone and sublactam in postmortem blood and may be useful in the evaluation of anaphylaxis.
  • Hajime Miyaguchi, Masaya Kakuta, Yuko T. Iwata, Hideaki Matsuda, Hidekatsu Tazawa, Hiroko Kimura, Hiroyuki Inoue
    JOURNAL OF CHROMATOGRAPHY A 1163(1-2) 43-48 2007年9月  査読有り
    We developed a rapid sample preparation method for the toxicological analysis of methamphetamine and amphetamine (the major metabolite of methamphetamine) in human hair by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), to facilitate fast screening and quantitation. Two milligrams of hair were mechanically micropulverized for 5 min in a 2-ml plastic tube together with 100 mu l of an aqueous solvent containing 10% acetonitrile, 100 mM trifluoroacetic acid and the corresponding deuterium analogues as internal standards. The pulverizing highly disintegrated the hair components, simultaneously allowing the extraction of any drugs present in the hair. After filtering the suspension with a membrane-filter unit, the clear filtrate was directly analyzed by HPLC-MS/MS. No evaporation processes were required for sample preparation. Method optimization and validation study were carried out using real-case specimens and fortified samples in which the drugs had been artificially absorbed, respectively. Concentration ranges for quantitation were 0.040-125 and 0.040-25 ng/mg for methamphetamine and amphetamine, respectively. Real-case specimens were analyzed by the method presented here and by conventional ones to verify the applicability of our method to real-world analysis. Our method took less than 30 min for a set of chromatograms to be obtained from a washed hair sample. (C) 2007 Elsevier B.V. All rights reserved.
  • Kenji Kuwayama, Hiroyuki Inoue, Tatsuyuki Kanamori, Kenji Tsujikawa, Hajime Miyaguchi, Yuko Iwata, Naoki Kamo, Tohru Kishi
    FORENSIC SCIENCE INTERNATIONAL 171(1) 9-15 2007年8月  査読有り
    Impurity profiling of methamphetamine (MA) using thermal desorption (TD) and gas chromatography-mass spectrometry (GC-MS) was examined. Using TD/GC-MS, impurities were extracted and separated under various conditions. Optimal chromatograms were obtained when a 20 mg MA sample was extracted at 120 degrees C for 3 min using a TD instrument, followed by separation of the extracts using a non-polar capillary column coated with (5%phenyl)-methylpolysiloxane. MA samples from nine different batches were analyzed under optimized conditions. Compounds related to the structure of MA, such as benzaldehyde, benzyl alcohol, amphetamine, cis- and traps-1,2-dimethyl-3-phenylaziridine, dimethylamphetamine, and N-acetylephedrine, were detected in the chromatograms without any laborious extraction procedure. Compounds such as ethanol, diethyl ether, and acetic acid, which are considered reagents and solvents for MA synthesis, were also detected in some of the chromatograms. The numbers and intensities of the peaks detected were different among the samples. Impurity profiling of MA using TD was compared with that using liquid-liquid extraction (LLE). Better reproducibility of peak areas was obtained using LLE, whereas higher intensities and numbers of peaks were detected using TD. Solvents were extracted more effectively using TD. The nine batches of MA were classified using both extraction procedures. The nine batches were divided roughly into two groups using data from LLE. Subsequently, the groups were classified in detail using data from TD. TD can be used to provide supplemental information for LLE, and the combination of these extraction methods can be helpful for impurity profiling of MA. (c) 2006 Elsevier Ireland Ltd. All rights reserved.
  • Kenji Kuwayama, Hiroyuki Inoue, Tatsuyuki Kanamori, Kenji Tsujikawa, Hajime Miyaguchi, Yuko Iwata, Seiji Miyauchi, Naoki Kamo, Tohru Kishi
    FORENSIC SCIENCE INTERNATIONAL 170(2-3) 183-188 2007年8月  査読有り
    Amphetamine-type stimulants (ATSs) are often abused orally in the form of tablets for recreational purposes. The ATS tablets contain one or more active ingredients such as 3,4-methylenedioxymethamphetamine (MDMA), methamphetamine (MA), ketamine (KA), and caffeine (CF). The aim of this work is to determine whether such components in tablets interact with each other in intestinal absorption. The interactions between MDMA, MA, KA, and CF in the uptake and permeation by human intestinal epithelial Caco-2 cell line were investigated in monolayer cultures. MDMA, MA, and KA mutually inhibited the uptakes by Caco-2 cells. The inhibition of MA uptake by KA was the greatest of all combinations (72.6% inhibition). Similarly, MDMA, MA, and KA mutually inhibited the permeation from the apical to the basolateral side through Caco-2 cells. Although CF did not affect the uptakes of MDMA, MA, and KA, CF enhanced the permeation of MDMA in comparison to MDMA alone. In addition, the interaction of MA with KA and that of MDMA with CF in intestinal absorption were investigated by oral administration to rats. The area under the plasma concentration-time curve of MA significantly decreased by co-administration with KA in comparison to MA alone, while that of MDMA significantly increased by co-administration with CF in comparison to MDMA alone. The results in rats were similar to those in Caco-2 cells. These findings suggest that the intestinal absorption of similar compounds with amine moieties such as MDMA, MA, and KA are mediated by a common transport system, and that CF affects the absorption of MDMA in a different way from the transport system. In human, intakes of ATS tablets mixed with such components might result in similar interactions in intestinal absorption to those in Caco-2 cells and rats. (c) 2007 Elsevier Ireland Ltd. All rights reserved.
  • Kenji Tsujikawa, Kenji Kuwayama, Hajime Miyaguchi, Tatsuyuki Kanamori, Yuko Iwata, Hiroyuki Inoue, Takemi Yoshida, Tohru Kishi
    JOURNAL OF CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIFE SCIENCES 852(1-2) 430-435 2007年6月  査読有り
    A reliable analytical method was developed for the quantification and identification of muscimol (MUS) and ibotenic acid (IBO), the toxic constituents of Amanita muscaria and Antanita pantherina. MUS and IBO were extracted from mushrooms by aqueous methanol and derivatized with dansyl chloride (DNS-CI). After extraction with ethyl acetate and evaporation of the solvent, the residue was ethylated with 1.25 M hydrogen chloride in ethanol. The resulting derivatives were quantified by high-performance liquid chromatography with UV detection and identified by liquid chromatography electrospray ionization tandem mass spectrometry. Calibration curves were linear in the range of 25-2500 ppm for MUS and 40-2500ppm for IBO, respectively. This method was successfully applied to identify and quantify MUS and IBO in Aminita mushrooms naturally grown and circulated in the drug market. (c) 2007 Elsevier B.V. All rights reserved.
  • T. Kanamori, K. Kuwayama, K. Tsujikawa, H. Miyaguchi, Y. T. Iwata, H. Inoue, T. Kishi
    XENOBIOTICA 37(6) 679-692 2007年6月  査読有り
    The in vivo metabolism of 2,5-dimethoxy-4-propylthiophenethylamine (2C-T-7), a ring-substituted psychoactive phenethylamine, was studied in rat. Male Wistar rats were administered 10mg/kg 2C-T-7 hydrochloride orally, and 24-h urine fractions were collected. After enzymatic hydrolysis of the urine sample, the metabolites were extracted by liquid-liquid extraction and analyzed by liquid chromatography/mass spectrometry. 2C-T-7-sulfoxide, N-acetyl-2C-T-7-sulfoxide, N-acetyl-2,5-dimethoxy-4-methylthiophenethylamine-sulfoxide, N-acetyl-2,5-dimethoxy-4-(2-hydroxypropylthio) phenethylamine-sulfoxide, and N-acetyl-2,5-dimethoxy-4-(2-hydroxypropylthio) phenethylamine-sulfone were detected as the primary metabolites of 2C-T-7. These findings suggest that sulfoxidation, sulfone formation, hydroxylation of the propyl side chain at the fi-position, and S-depropylation followed by methylation of thiol were the major metabolic pathways of 2C-T-7 in rat.
  • 金森達之, 桑山健次, 辻川健治, 宮口一, 岩田祐子, 井上博之, 岸徹
    日本法科学技術学会誌 12 237-245 2007年  査読有り
  • Kenji Tsujikawa, Hiroyuki Mohri, Kenji Kuwayama, Hajime Miyaguchi, Yuko Iwata, Akinaga Gohda, Sunao Fukushima, Hiroyuki Inoue, Tohru Kishi
    FORENSIC SCIENCE INTERNATIONAL 164(2-3) 172-178 2006年12月  査読有り
    The constituents of seven mushrooms sold as Amanita muscaria or Amanita pantherina (five A. muscaria and two A. pantherina) and four "extracts purported to contain A. muscaria" products that are currently circulated in Japan were determined. All mushroom samples were identified as A. muscaria or A. pantherina by macroscopic and microscopic observation. The dissociative constituents, ibotenic acid (IBO) and muscimol (MUS), were extracted with 70% methanol twice and determined by gas chromatography/mass spectrometry. The IBO (as the hydrate)/ MUS contents were in the range of &lt; 10-2845 ppm/46-1052 ppm in the cap of A. muscaria and 188-269 ppm/1554-1880 ppm in the cap of A. pantherina. In the caps, these compounds had a tendency to be more concentrated in the flesh than in the cuticle. On the other hand, the IBO/MUS contents in the stem were far lower than in the caps. In the "extracts purported to contain A. muscaria" products, IBO/MUS were detected below the lower limit of calibration curve (&lt; 10 ppm/&lt; 25 ppm) or not detected. However, these samples contained other psychoactive compounds, such as psychoactive tryptamines (5-methoxy-N,N-diisopropyltryptamine and 5-rriethoxy-N,N-dimethyltryptamine), reversible monoamine oxidase inhibitors (harmine and harmaline) and tropane alkaloids (atropine and scopolamine), which were not quantified. This is the first report of the chemical analysis of Amanita mushrooms that are circulated in the drug market. (c) 2006 Elsevier Ireland Ltd. All rights reserved.
  • Hajime Miyaguchi, Manabu Tokeshi, Yoshikuni Kikutani, Akihide Hibara, Hiroyuki Inoue, Takehiko Kitamori
    JOURNAL OF CHROMATOGRAPHY A 1129(1) 105-110 2006年9月  査読有り
    A microchip-based liquid-liquid extraction for the gas chromatography analysis of urine for amphetamine-type stimulants has been developed. Partially modified microchannels with the capillarity restricted modification (CARM) method were employed for stabilizing the interface consisting of 1-chlorobutane and alkalized urine. Reliability of the microchip-based extraction was evaluated with respect to linearity, trueness and precision. As a practical demonstration, methoxyphenamine hydrochloride (50 mg) was administered to three healthy volunteers, and the concentration of methoxyphenamine in their urine was determined by both methods for comparison. This study showed the potential of pressure-driven microfluidics to contribute to the rapid automation analysis in forensic toxicology. (c) 2006 Elsevier B.V. All rights reserved.
  • Yuko T. Iwata, Hiroyuki Inoue, Kenji Kuwayama, Tatsuyuki Kanamori, Kenji Tsujikawa, Hajime Miyaguchi, Tohru Kishi
    FORENSIC SCIENCE INTERNATIONAL 161(2-3) 92-96 2006年9月  査読有り
    The applicability of capillary electrophoresis (CE) with a UV detector using highly sulfated gamma-cyclodextrin as a chiral selector was examined for analysis of impurities in seized methamphetamine. Samples of methamphetamine-hydrochloride dissolved in water at a high concentration (20 mg/mL) were analyzed. Electrokinetic injection has an advantage over hydrodynamic injection for improving the detection of trace impurities. Small peaks of the precursor impurities, such as (1R,2S)-(-)-ephedrine and (1S,2S)-(+)-pseudoephedrine, were detected and quantified without extraction. The seized drugs could be classified into three groups based on the contents of the two impurities. (c) 2006 Elsevier Ireland Ltd. All rights reserved.
  • Tatsuyuki Kanamori, Kenji Kuwayama, Kenji Tsujikawa, Hajime Miyaguchi, Yuko Iwata, Hiroyuki Inoue, Tohru Kishi
    JOURNAL OF HEALTH SCIENCE 52(4) 425-430 2006年8月  査読有り
    The in vivo metabolism of 5-methoxy-NA-diiso-propyltryptamine (5-MeO-DIPT), a psychoactive tryptamine analog, was studied in rat. Male Wistar rats were administered 10 mg/kg 5-MeO-DIPT hydrochloride orally, and urinary fractions were collected. After enzymatic hydrolysis, the metabolites were extracted by liquid-liquid extraction and analyzed by gas chromatography/mass spectrometry. 5-Methoxy-N-isopropyltryptamine, 5-hydroxy-N,N-diisopropyltryptamine (5-OH-DIPT), 5-hydroxy-N-isopropyltryptamine, and 5-methoxyindole-3-acetic acid were identified as 5-MeO-DIPT metabolites. By quantitative analysis using high-performance liquid chromatography, it was revealed that 5-OH-DIPT was the main metabolite of 5-MeO-DIPT in rat, comprising 20.5% of the dose administered. On the other hand, only 0.8% of 5-MeO-DIPT administered was excreted into the urine in its original form.
  • Kenji Kuwayama, Kenji Tsujikawa, Hajime Miyaguchi, Tatsuyuki Kanamori, Yuko Iwata, Hiroyuki Inoue, Shuji Saitoh, Tohru Kishi
    FORENSIC SCIENCE INTERNATIONAL 160(1) 44-52 2006年6月  査読有り
    The profiling of impurities in methamphetamine (MA) using headspace solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) is described. The extraction of the impurities with an SPME fiber was examined under varying conditions. Optimal chromatograms were obtained when a 50 mg MA sample at 85 degrees C for 30 min was extracted using a fiber coated with divinylbenzene/carboxen/polydimethylsiloxane. MA samples from nine different origins were analyzed under optimized extraction conditions. Compounds related to MA such as benzaldehyde, benzyl alcohol, amphetamine, benzyl methyl ketone, cis- and trans-1,2-dimethyl-3-phenylaziridine, dimethylamphetamine, N-acetylamphetamine, N-acetylmethamphetamine and N-formylmethamphetamine were detected in the chromatograms. Trace amounts of ethanol, diethyl ether and acetic acid were also detected in some of the chromatograms. The numbers and intensities of the peaks detected were different, depending on the sample. After the areas of the eight principal peaks were converted to their square root and logarithm, similarities among the samples were evaluated by Euclidian distance, cosine distance and correlation coefficient. The results showed that a combination of logarithmic conversion and cosine distance was the most suitable for discriminating and classifying the samples. HS-SPME/GC-MS is a simple and effective method for the extraction and identification of impurities. The present method, in combination with an appropriate statistical analysis, would be useful for developing a profile of impurities in MA. (c) 2005 Elsevier Ireland Ltd. All rights reserved.

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