46 results on '"Michiaki Tatsuno"'
Search Results
2. Metabolism of the newly encountered designer drug α-pyrrolidinovalerophenone in humans: identification and quantitation of urinary metabolites
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Takako Sato, Akihiro Miki, Kei Zaitsu, Akira Ishii, Noriaki Shima, Shuntaro Matsuta, Keiko Sasaki, Hiroe Kamata, Tohru Kamata, Hitoshi Tsuchihashi, Munehiro Katagi, Michiaki Tatsuno, Hiroshi Nishioka, and Koichi Suzuki
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Chromatography ,Valerophenone ,medicine.drug_class ,Stereochemistry ,Biochemistry (medical) ,technology, industry, and agriculture ,Diastereomer ,macromolecular substances ,Toxicology ,Mass spectrometry ,Pyrrolidine ,Pathology and Forensic Medicine ,Designer drug ,chemistry.chemical_compound ,Metabolic pathway ,chemistry ,medicine ,Moiety ,Glucuronide - Abstract
Urinary metabolites of α-pyrrolidinovalerophenone (α-PVP) in humans were investigated by analyzing urine specimens obtained from abusers. Unambiguous identification and accurate quantification of major metabolites were realized using gas chromatography–mass spectrometry and liquid chromatography-tandem mass spectrometry with newly synthesized authentic standards. Two major metabolic pathways were revealed: (1) the reduction of the β-keto moiety to 1-phenyl-2-(pyrrolidin-1-yl)pentan-1-ol (OH-α-PVP, diastereomers) partly followed by conjugation to its glucuronide, and (2) the oxidation at the 2″-position of the pyrrolidine ring to α-(2″-oxo-pyrrolidino)valerophenone (2″-oxo-α-PVP) via the putative intermediate α-(2″-hydroxypyrrolidino)valerophenone (2″-OH-α-PVP). Of the metabolites retaining the structural characteristics of the parent drug, OH-α-PVP was most abundant in most of the specimens examined.
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- 2013
3. Mass spectrometric differentiation of the isomers of mono-methoxyethylamphetamines and mono-methoxydimethylamphetamines by GC–EI–MS–MS
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Koichi Suzuki, Yuki Sakamoto, Shuntaro Matsuta, Kento Tsuboi, Takako Sato, Hiroshi Nishioka, Haruhiko Miyagawa, Kei Zaitsu, Michiaki Tatsuno, Hitoshi Tsuchihashi, Akira Ishii, and Munehiro Katagi
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Designer drug ,Chromatography ,Chemistry ,medicine.drug_class ,Biochemistry (medical) ,medicine ,Toxicology ,Mass spectrometry ,Mass spectrometric ,Dissociation (chemistry) ,Pathology and Forensic Medicine ,Ion - Abstract
Mass spectrometric differentiation of the six isomers of mono-methoxyethylamphetamines (MeO-EAs) and mono-methoxydimethylamphetamines (MeO-DMAs) by gas chromatography–electron ionization–tandem mass spectrometry (GC–EI–MS–MS) was investigated. Based on their EI-mass spectra, the fragment ions at m/z 121 and 72 were selected as precursor ions for their regioisomeric and structurally isomeric differentiation, respectively. Collision-induced dissociation provides intensity differences in product ions among the isomers, enabling mass spectrometric differentiation of the isomers. Furthermore, high reproducibility of the product ion spectra at the optimized collision energy was confirmed, demonstrating the reliability of the method. To our knowledge, this is the first report on mass spectrometric differentiation of the six isomers of MeO-EAs and MeO-DMAs by GC–EI–MS–MS. Isomeric differentiation by GC–EI–MS–MS has a high potential to discriminate isomers of newly encountered designer drugs, making GC–MS–MS a powerful tool in the forensic toxicology field.
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- 2013
4. Urinary excretion and metabolism of the newly encountered designer drug 3,4-dimethylmethcathinone in humans
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Michiaki Tatsuno, Takako Sato, Akihiro Miki, Tooru Kamata, Koichi Suzuki, Kei Zaitsu, Hitoshi Tsuchihashi, Hiroe Kamata, Munehiro Katagi, Hiroshi Nishioka, Keiko Nakanishi, Noriaki Shima, and Shuntaro Matsuta
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chemistry.chemical_classification ,Ketone ,Chromatography ,medicine.drug_class ,Biochemistry (medical) ,Alcohol ,Metabolism ,Toxicology ,3,4-Dimethylmethcathinone ,Pathology and Forensic Medicine ,Designer drug ,chemistry.chemical_compound ,Metabolic pathway ,chemistry ,Biochemistry ,Enzymatic hydrolysis ,medicine ,Amine gas treating - Abstract
Cathinone-derived designer drugs have recently grown to be popular as drugs of abuse. 3,4-Dimethylmethcathinone (DMMC) has recently been abused as one of the alternatives to controlled cathinones. In the present study, DMMC and its major metabolites, 3,4-dimethylcathinone (DMC), 1-(3,4-dimethylphenyl)-2-methylaminopropan-1-ol (β-OH-DMMC, diastereomers), and 2-amino-1-(3,4-dimethylphenyl)propan-1-ol (β-OH-DMC, diastereomers), have been identified and quantified in a DMMC user’s urine by gas chromatography–mass spectrometry and liquid chromatography–tandem mass spectrometry using newly synthesized authentic standards. Other putative metabolites including oxidative metabolites of the xylyl group and conjugated metabolites have also been detected in urine. The identified and putative phase I metabolites indicated that the metabolic pathways of DMMC include its reduction of the ketone group to the corresponding alcohols, N-demethylation to the primary amine, oxidation of the xylyl group to the corresponding alcohol and carboxylate forms, and combination of these steps. Concentrations of the identified metabolites were found to increase slightly after enzymatic hydrolysis, suggesting that these compounds are partially metabolized to the respective conjugates.
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- 2012
5. Recently abused β-keto derivatives of 3,4-methylenedioxyphenylalkylamines: a review of their metabolisms and toxicological analysis
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Michiaki Tatsuno, Takako Sato, Kei Zaitsu, Munehiro Katagi, Hitoshi Tsuchihashi, and Koichi Suzuki
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Chromatography ,Chemistry ,Methylone ,Biochemistry (medical) ,medicine ,Clinical toxicology ,Toxicology ,Mass spectrometry ,Pathology and Forensic Medicine ,medicine.drug - Abstract
β-Keto derivatives of 3,4-methylenedioxyphenylalkylamines (bk-MDPAs), especially 2-methylamino-1-(3,4-methylenedioxyphenyl)propan-1-one (methylone), 2-methylamino-1-(3,4-methylenedioxyphenyl)butan-1-one (bk-MBDB), and 2-ethylamino-1-(3,4-methylenedioxyphenyl)propan-1-one (bk-MDEA), are abused as substitutes for 3,4-methylenedioxyphenylalkylamines in some countries, causing increased social problems. With the widespread abuse of bk-MDPAs, the analysis of bk-MDPAs and their metabolites in human specimens is quite important in forensic and clinical toxicology. In this review, the metabolisms of bk-MDPAs and simultaneous analytical methods for bk-MDPAs and their metabolites by gas chromatography–mass spectrometry, liquid chromatography–mass spectrometry, and liquid chromatography–tandem mass spectrometry are presented.
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- 2011
6. Imaging of methamphetamine incorporated into hair by MALDI-TOF mass spectrometry
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Michiaki Tatsuno, Munehiro Katagi, Toyofumi Nakanishi, Noriaki Shima, Koichi Suzuki, Takayuki Takubo, Hitoshi Tsuchihashi, Hiroe Kamata, and Akihiro Miki
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Chromatography ,Desorption ionization ,integumentary system ,Chemistry ,Biochemistry (medical) ,Hair analysis ,Hair shaft ,Forensic toxicology ,Passive Exposure ,Methamphetamine ,Toxicology ,Mass spectrometry ,MALDI-TOF Mass Spectrometry ,Pathology and Forensic Medicine ,medicine ,medicine.drug - Abstract
Matrix-assisted laser desorption ionization (MALDI)–time-of-flight (TOF) mass spectrometry (MS) was used for visual demonstration of methamphetamine (MA) incorporation into human hair. Longitudinal sections of human scalp hair shafts from chronic MA users were directly subjected to imaging MS. Numerous MA-positive spots with various intensities were observed in the specimens, which probably reflect habitual MA abuse and the different MA blood levels upon each administration. This imaging MS method for drugs in hair seems to give much more accurate chronological information on drug use, and clearer discrimination between deliberate drug use and passive exposure, using only a single hair shaft. This is the first report of imaging MS applied to forensic toxicology. This method is expected open a new field in analyses of drugs in hair.
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- 2011
7. MALDI-TOF and MALDI-FTICR imaging mass spectrometry of methamphetamine incorporated into hair
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Munehiro Katagi, Takayuki Takubo, Michiaki Tatsuno, Hitoshi Tsuchihashi, Akihiro Miki, Tooru Kamata, Koichi Suzuki, Toyofumi Nakanishi, and Kei Zaitsu
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Chromatography ,integumentary system ,Resolution (mass spectrometry) ,Chemistry ,Selected reaction monitoring ,Analytical chemistry ,Mass spectrometry ,Fourier transform ion cyclotron resonance ,Mass spectrometry imaging ,Methamphetamine ,Molecular Imaging ,Substance Abuse Detection ,Matrix (chemical analysis) ,Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ,Spectroscopy, Fourier Transform Infrared ,Mass spectrum ,Humans ,Spectroscopy ,Ion cyclotron resonance ,Hair - Abstract
A new approach is described for imaging mass spectrometry (IMS) of methamphetamine (MA) incorporated into human hair using matrix-assisted laser desorption/ionization (MALDI)-time-of-flight (TOF) and MALDI-Fourier transform ion cyclotron resonance (FTICR). A longitudinal section of a lengthwise manually-cut single human hair shaft from a chronic MA user was directly analyzed by MALDI-TOF-IMS after deposited with α-Cyano-4-hydroxycinnamic acid matrix. A barcode-like image, which was most probably generated with repeated intakes of MA, was for the first time obtained by monitoring MA-specific product ion in the selected reaction monitoring mode. Laser beam scan lengthwise-cut hair shafts gave only poor mass spectra of MA, probably due to the loss of MA and/or the thermal denaturation of hair. The identity of MA detected in hair was further confirmed by MALDI-FTICR mass spectrometry. A combination with ultra-high resolution mass spectrometry by FTICR provided indisputable identification of MA. The MALDI-FTICR-IMS of another hair shaft from the same MA user also provided a barcode-like image by monitoring the protonated molecule of MA with ultra-high resolution. The two barcode-like images exhibited a close resemblance. Thus, MALDI-IMS can offer a new perspective: 'imaging hair analyses for drugs'.
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- 2011
8. Comprehensive Analytical Methods of the Synthetic Cannabinoids Appearing In the Illicit Drug Market
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Hiroshi Nishioka, Keiko Nakanishi, Michiaki Tatsuno, Takako Sato, Munehiro Katagi, Noriaki Shima, Tooru Kamata, Akihiro Miki, Hiroe Kamata, Tatsunori Iwamura, Kei Zaitsu, Koichi Suzuki, and Hitoshi Tsuchihashi
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Chromatography ,medicine.drug_class ,Chemistry ,Electrospray ionization ,Analytical chemistry ,Poison control ,Tandem mass spectrometry ,Mass spectrometry ,Thin-layer chromatography ,Designer drug ,Synthetic cannabinoids ,medicine ,Gas chromatography ,medicine.drug - Abstract
Comprehensive analytical method to identify 11 kinds of synthetic cannabinoids has been investigated by thin layer chromatography (TLC), gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/tandem mass spectrometry (LC/MS/MS). The analytes used in this study have already been detected from various herbal-type designer drugs: 8 kinds of aminoalkylindoles (AAIs) (JWH-015, JWH-018, JWH-073, JWH-081, JWH-200, JWH-250, JWH-251 and JWH-398), two kinds of cyclohexylphenols (CPs) (CP 47,497 and Cannabicyclohexanol), and a Δ9-tetrahydrocannabinol analog (HU-210). Although specific color changes were observed for the cannabinoids using Marquis reagent, identification of each analyte based on Rf values was difficult to be obtained by TLC. On the other hand, GC/MS and LC/MS/MS were appropriate for their qualitative analyses because of their chromatographic and mass spectral differentiation. A semi-polar capillary column DB-5MS showed the best separation and retention properties of the targeted cannabinoids among the tested GC column phases. Also, characteristic fragment ions were observed in each electron ionization-mass spectrum. The observed fragment ions were mainly derived from α-cleavage of ketone and α-cleavage of amine for AAIs, simple cleavage for CPs, and McLafferty rearrangements for HU-210. Based on the ionization efficiency of the target analytes using LC/MS/MS, electrospray ionization positive mode was selected for AAIs, and negative mode for CPs and HU-210. All analytes were completely separated by gradient elution of ammonium formate aqueous solution-acetonitrile mobile phase on a C18 (ODS) separation column. In addition, characteristic fragment ions were observed in product ion spectra of AAIs and second generation product ion spectra of CPs and HU-210, enabling reliable confirmation. These results provide useful information not only for simultaneous analyses of the targeted cannabinoids but also for structural assignment of future cannabimimetic compounds that may appear in the illicit drug market.
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- 2011
9. Simultaneous analysis of six novel hallucinogenic (tetrahydrobenzodifuranyl)aminoalkanes (FLYs) and (benzodifuranyl)aminoalkanes (DragonFLYs) by GC-MS, LC-MS, and LC-MS-MS
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Tooru Kamata, Hitoshi Tsuchihashi, Michiaki Tatsuno, Keiko Nakanishi, Kei Zaitsu, Noriaki Shima, Hiroshi Nishioka, Akihiro Miki, Hiroe Kamata, and Munehiro Katagi
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Chromatography ,Biochemistry (medical) ,Toxicology ,Mass spectrometry ,Pathology and Forensic Medicine ,chemistry.chemical_compound ,chemistry ,Liquid chromatography–mass spectrometry ,Dehydrogenation ,Gas chromatography ,Trifluoroacetic anhydride ,Gas chromatography–mass spectrometry ,Derivatization ,Triethylamine - Abstract
Six novel hallucinogens classed as (tetrahydrobenzodifuranyl) aminoalkanes or (benzodifuranyl)aminoalkanes, which are known by the common names of “FLY” and “DragonFLY,” respectively, were synthesized. These compounds were simultaneously analyzed by gas chromatography (GC)-mass spectrometry (MS), liquid chromatography (LC)-MS, and LC-MS-MS. GCMS analysis of their free bases was not satisfactory for both mass spectral and chromatographic measurements, and thus trifluoroacetyl (TFA) derivatization was employed. However, it was found that the usual TFA derivatization procedure using trifluoroacetic anhydride caused dehydrogenation of FLYs to the corresponding DragonFLYs. Therefore, TFA derivatization of FLYs was reinvestigated; the presence of triethylamine could almost inhibit such dehydrogenation. LC separation of the analytes was successfully achieved by using a phenyl-type semimicro column with methanol gradient elution, while 1-(8-bromo-2,3,6,7-tetrahydrobenzo[1,2-b;4,5-b′]difuran-4-yl)-2-methylaminopropane (N-methyl-DOB-FLY) and 1-(8-bromo-2,3,6,7-tetrahydrobenzo[1,2-b;4,5-b′]difuran-4-yl)-2-aminopropane (DOB-FLY) were not separated on an octadecylsilica (ODS)-type column. Specific product ion spectra for all compounds were also obtained using LC-MS-MS, which enabled sensitive and reliable identification.
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- 2009
10. Noninvasive Inspection of C-4 Explosive in Mails by Terahertz Time-Domain Spectroscopy
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Kenji Koide, Michiaki Tatsuno, Fumiaki Miyamaru, Yukio Minami, Masanori Hangyo, Kohji Yamamoto, Akira Matsushita, Takeshi Ikeda, Mariko Yamaguchi, and Masahiko Tani
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Materials science ,Physics and Astronomy (miscellaneous) ,Explosive material ,Absorption spectroscopy ,business.industry ,Terahertz radiation ,General Engineering ,General Physics and Astronomy ,Terahertz spectroscopy and technology ,Optics ,Attenuation coefficient ,Optoelectronics ,business ,Spectroscopy ,Terahertz time-domain spectroscopy ,Refractive index - Abstract
We have measured the refractive index, extinction coefficient, and absorption coefficient of the explosive C-4 by THz time-domain spectroscopy and examined its applicability to detecting C-4 in mails. The explosive C-4, which is used in almost all mail-bomb terrorist activities, shows six THz bands in the frequency region from 5 to 90 cm-1 (150 GHz–2.7 THz). The 26.9 cm-1 band is very strong and can be used as a fingerprint of C-4. We confirmed that the THz absorption spectrum of C-4 hidden inside an envelope coincides essentially with that of C-4 itself. We also examined the applicability of the THz reflection spectroscopy to C-4 detection by calculating the reflectance spectra. Our results demonstrate that the THz techniques are very promising for counterterrorism against C-4 mail bombs.
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- 2004
11. Application of Assay of Platelet Monoamine Oxidase Type-B (MAO-B) Activity to the Discrimination of Selegiline Use from Methamphetamine Abuse
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Michiaki Tatsuno, Hiroe Tsutsumi, Hitoshi Tsuchihashi, Hiroshi Nishioka, Akihiro Miki, Tohru Kamata, Kunio Nakajima, and Munehiro Katagi
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Hydrochloride ,Health, Toxicology and Mutagenesis ,Selegiline ,Oxidative deamination ,Methamphetamine ,Pharmacology ,Toxicology ,In vitro ,chemistry.chemical_compound ,chemistry ,In vivo ,medicine ,Platelet ,Monoamine oxidase B ,medicine.drug - Abstract
An assay of platelet monoamine oxidase type-B (MAO-B) activity has been explored in the search for a reliable method of discriminating selegiline (SG) use from methamphetamine (MA) abuse. MAO-B activity was measured by fluorimetry of 4-hydroxyquinoline (4HOQ) produced by oxidative deamination of kynuramine, the substrate for MAO-B. MA and most of its related compounds including its precursors produced no platelet MAO-B inhibition in vitro even at their lethal levels, though SG, its specific metabolites selegiline N-oxide (SGO) and N-desmethylselegiline (DM-SG), as well as its enantiomer d-deprenyl exhibited high platelet MAO-B inhibitory potency. In vivo, remarkable inhibition of MAO-B occurred even within an hour after drug administration, and the inhibition apparently lasted approximately 6-8 days after both 2.5 and 7.5 mg oral doses of SG hydrochloride. The present study suggests that the decrease of platelet MAO-B activity would be a significant marker to discriminate SG use from MA abuse, even a week after drug use.
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- 2003
12. Simultaneous Determination of Eleven Benzodiazepine Hypnotics and Eleven Relevant Metabolites in Urine by Column-Switching Liquid Chromatography-Mass Spectrometry
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Hitoshi Tsuchihashi, Mayumi Nishikawa, Munehiro Katagi, Akihiro Miki, and Michiaki Tatsuno
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Detection limit ,Spectrometry, Mass, Electrospray Ionization ,Chemical ionization ,Analyte ,Chemical Health and Safety ,Chromatography ,Chemistry ,Health, Toxicology and Mutagenesis ,Forensic Medicine ,Toxicology ,Mass spectrometry ,Sensitivity and Specificity ,High-performance liquid chromatography ,Analytical Chemistry ,Substance Abuse Detection ,Benzodiazepines ,Liquid chromatography–mass spectrometry ,Humans ,Environmental Chemistry ,Anticonvulsants ,Sample preparation ,Solid phase extraction ,Chromatography, High Pressure Liquid - Abstract
An automated column-switching liquid chromatographic-atmospheric pressure chemical ionization-mass spectrometric (LC-APCI-MS) method for the simultaneous determination of frequently encountered benzodiazepine hypnotics and their relevant metabolites in urine has been established. A column-switching online solid-phase extraction technique was employed to enhance sensitivity and eliminate tedious sample pretreatment. The combination of an N-vinylacetamide-containing hydrophilic polymer online extraction column and a C18 semi-micro LC column provided the successful separations and MS determinations of the 11 benzodiazepines and 11 relevant metabolites tested in this study. The detection limits ranged 2-10 ng/mL and 10-50 ng/mL in the SIM and full-scan modes, respectively, using 50 microL of urine. The calibration curves were linear up to 500 ng/mL for all these analytes in the SIM mode. The present method provided successful forensic applications for the proof of benzodiazepine administration.
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- 2002
13. Simultaneous determination of selegiline-N-oxide, a new indicator for selegiline administration, and other metabolites in urine by high-performance liquid chromatography–electrospray ionization mass spectrometry
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Kunio Nakajima, Hitoshi Tsuchihashi, Mayumi Nishikawa, Munehiro Katagi, Michiaki Tatsuno, and Akihiro Miki
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Detection limit ,Spectrometry, Mass, Electrospray Ionization ,Chemical ionization ,Monoamine Oxidase Inhibitors ,Chromatography ,Chemistry ,Electrospray ionization ,Metabolite ,Reproducibility of Results ,General Chemistry ,Mass spectrometry ,Sensitivity and Specificity ,High-performance liquid chromatography ,chemistry.chemical_compound ,Selegiline ,Humans ,Selected ion monitoring ,Solid phase extraction ,Chromatography, High Pressure Liquid - Abstract
In order to discriminate selegiline (SG) use from methamphetamine (MA) use, the urinary metabolites of SG users have been investigated using high-performance liquid chromatography (HPLC)-electrospray ionization mass spectrometry (HPLC-ESI-MS). Selegiline-N-oxide (SGO), a specific metabolite of SG, was for the first time detected in the urine, in addition to other metabolites MA, amphetamine (AP) and desmethylselegiline (DM-SG). A combination of a Sep-pak C18 cartridge for the solid-phase extraction, a semi-micro SCX column (1.5 mm I.D.x 150 mm) for HPLC separation and ESI-MS for detection provided a simple and sensitive procedure for the simultaneous determination of these analytes. Acetonitrile-10 mM ammonium formate buffer adjusted to pH 3.0 (70:30, v/v) at a flow-rate of 0.1 ml/min was found to be the most effective mobile phase. Linear calibration curves were obtained over the concentration range from 0.5 to 100 ng/ml for all the analytes by monitoring each protonated molecular ion in the selected ion monitoring (SIM) mode. The detection limits ranged from 0.1 to 0.5 ng/ml. Upon applying the scan mode, 10-20 ng/ml were the detection limits. Quantitative investigation utilizing this revealed that SGO was about three times more abundant (47 ng/ml, 79 ng/ml) than DM-SG in two SG users' urine samples tested here. This newly-detected, specific metabolite SGO was found to be an effective indicator for SG administration.
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- 2001
14. Column-switching high-performance liquid chromatography–electrospray ionization mass spectrometry for identification of heroin metabolites in human urine
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Michiaki Tatsuno, Akihiro Miki, Hitoshi Tsuchihashi, Mayumi Nishikawa, and Munehiro Katagi
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Male ,Detection limit ,Spectrometry, Mass, Electrospray Ionization ,Electrospray ,Chromatography ,Electrospray ionization ,Analytical chemistry ,General Chemistry ,Mass spectrometry ,Sensitivity and Specificity ,High-performance liquid chromatography ,Heroin ,Substance Abuse Detection ,chemistry.chemical_compound ,chemistry ,Humans ,Selected ion monitoring ,Solid phase extraction ,Ammonium acetate ,Chromatography, High Pressure Liquid - Abstract
In order to prove heroin (DAM) use, a simple, rapid and sensitive analytical method has been established by combining semi-microcolumn HPLC, a column switching technique and electrospray ionization mass spectrometry (ESI-MS). Urine samples were directly introduced to the system, and endogenous urinary constituents were removed by using on-line column switching solid-phase extraction with a strong cation-exchange (SCX) cartridge column (2.0 mm I.D. x 10 mm). Heroin and its metabolites enriched on the top of the column were then successfully analyzed with excellent separation by use of a SCX semi-microcolumn (1.5 mm I.D. x 150 mm), accompanied by ESI mass spectral detection. The proposed conditions are as follows: mobile phase, 10 mM ammonium acetate (pH 6.0)-acetonitrile (30:70, v/v) (for main separation) and 30 mM ammonium acetate (for trapping); flow-rates, 120 microl/min (for main separation) and 200 microl/min (for trapping); capillary voltage, +4.5 kV; cone voltage, 50 V. Linear calibration curves were obtained in the selected ion monitoring (SIM) mode using protonated molecular ions (m/z 370 for DAM, m/z 328 for MAM and m/z 286 for MOR) over the concentration ranges from 10 to 1000 ng/ml for morphine (MOR) and 1-100 ng/ml for DAM and 6-acetylmorphine (MAM). The detection limits were 0.1-3 ng/ml. Upon applying the scan mode, 2-30 ng/ml were the detection limits. The present HPLC-ESI-MS method was successfully applied to the determination of opiates in users' urine samples.
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- 2001
15. A novel degradative pathway of 2-nitrobenzoate via 3-hydroxyanthranilate inPseudomonas fluorescensstrain KU-7
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Hiroaki Iwaki, Takamichi Muraki, Yoshie Hasegawa, Tai Tokuyama, Peter C. K. Lau, and Michiaki Tatsuno
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biology ,Chemistry ,Metabolite ,3-Hydroxyanthranilic Acid ,Water Pollution ,Pseudomonas ,Pseudomonas fluorescens ,Metabolism ,biology.organism_classification ,Microbiology ,Thin-layer chromatography ,Culture Media ,chemistry.chemical_compound ,Metabolic pathway ,Biodegradation, Environmental ,Petroleum ,Biochemistry ,Nitrobenzoates ,Genetics ,Water Microbiology ,Molecular Biology ,Soil Microbiology ,Bacteria ,Pseudomonadaceae - Abstract
A bacterial strain KU-7, identified as a Pseudomonas fluorescens by 16S rDNA sequencing, was one of the 12 new isolates that are able to grow on 2-nitrobenzoate as a sole source of carbon, nitrogen, and energy. Resting cells of KU-7 were found to accumulate ammonia in the medium indicating that degradation of 2-NBA proceeds through a reductive route. Metabolite analyses by thin layer chromatography and high pressure liquid chromatography indicated that 3-hydroxyanthranilate is an intermediate of 2-nitrobenzoate metabolism in KU-7 cells. This offers an alternative route to 2-nitrobenzoate metabolism since anthranilate (2-aminobenzoate) or catechol were detected as intermediates in other bacteria. Crude extracts of KU-7 cells converted 2-nitrobenzoate to 3-hydroxyanthranilate with oxidation of 2 mol of NADPH. Ring cleavage of 3-hydroxyanthranilate produced a transient yellow product, identified as 2-amino-3-carboxymuconic 6-semialdehyde, that has a maximum absorbance at 360 nm. The initial enzymes of the 2-nitrobenzoate degradation pathway were found to be inducible since succinate-grown cells produced very low enzyme activities. A pathway for 2-nitrobenzoate degradation in KU-7 was proposed.
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- 2000
16. [Untitled]
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Hiroshi Nishioka, Mayumi Nishikawa, Munehiro Katagi, Michiaki Tatsuno, and Hitoshi Tsuchihashi
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- 2000
17. Determination of Bromvalerylurea and Its Metabolites in Biological Samples by Frit-Fast Atom Bombardment Liquid Chromatography-Mass Spectrometry
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Fumiyo Kasuya, Kazuo Igarashi, Miyoshi Fukui, Michiaki Tatsuno, Mayumi Nishikawa, Munehiro Katagi, and Hitoshi Tsuchihashi
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Male ,Chemical Health and Safety ,Chromatography ,Chemistry ,Elution ,Health, Toxicology and Mutagenesis ,Fast atom bombardment ,Toxicology ,Mass spectrometry ,High-performance liquid chromatography ,Mass Spectrometry ,Rats ,Analytical Chemistry ,Liver ,Liquid chromatography–mass spectrometry ,Animals ,Humans ,Hypnotics and Sedatives ,Environmental Chemistry ,Sample preparation ,Solid phase extraction ,Bromisovalum ,Rats, Wistar ,Quantitative analysis (chemistry) ,Chromatography, Liquid - Abstract
A simple, rapid, and sensitive method which allows us to simultaneously determine bromvalerylurea (BVU) and its three metabolites (3-methylbutyrylurea [MVU], alpha-(cystein-S-yl)isovalerylurea [CVU], and alpha-(N-acetylcystein-S-yl)isovalerylurea [AcCVU]) was investigated by frit-fast atom bombardment liquid chromatography-mass spectrometry (frit-FAB LC-MS). The LC-MS analysis was performed after the solid-phase extraction from tissue and urine samples with a Sep-Pak C18 cartridge. Tissue homogenates and urine were adjusted to pH 4.0 and applied to the cartridges. The retained BVU and its metabolites were eluted from the cartridge with 2 mL of acetonitrile/10 mM ammonium acetate buffer (pH 3.5, 50:50, v/v). The eluate was analyzed by LC-MS, which employs a semimicro type L-column ODS column. The proposed conditions are as follows: mobile phase A, 0.4% glycerol in acetonitrile/10 mM ammonium acetate buffer (pH 3.5) (5:95, v/v); mobile phase B, 0.4% glycerol in acetonitrile; elution mode, linear gradient, 100% A (5 min) to 100% B in 15 min; flow rate, 0.2 mL/min; split ratio, 1:40. Extraction recoveries of BVU and its metabolites were 91.90-97.79% from the spiked liver homogenate and 89.68-96.13% from the spiked urine. The detection limits ranged from 10 to 25 ng/g in selected ion monitoring mode.
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- 1998
18. Direct Analysis of Methamphetamine and Amphatamine Enantiomers in Human Urine by Semi-microcolumn HPLC/Electrospray Ionization Mass Spectrometry
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Michiaki Tatsuno, Mayumi Nishikawa, Munehiro Katagi, Hitoshi Tsuchihashi, Tadashi Miyazawa, Ayako Suzuki, and Osamu Shirota
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Detection limit ,Analyte ,chemistry.chemical_compound ,Chromatography ,Resolution (mass spectrometry) ,chemistry ,Calibration curve ,Metabolite ,Electrospray ionization ,Analytical chemistry ,Enantiomer ,Toxicology ,High-performance liquid chromatography - Abstract
Semi-microcolumn high performance liquid chromatography (HPLC) with a columnswitching system was connected to electrospray ionization mass spectrometry (ESI-MS) for the analysis of methamphetamine (MA) and amphetamine (AP), a main metabolite of MA. Urine samples were directly introduced to the system. After removal of other components of the sample matrix by the column-switching process, both MA and AP were successfully analyzed with enantiomeric resolution by the use of β-cyclodextrin phenylcarbamate-bonded (phCD) semi-microcolumn, accompanied by spectral information obtained with ESI-MS. Linear calibration curves were obtained for all the analytes throughout the concentration range from 1 ng/ml to 5 μg/ml. The relative standard deviation for peak area ranged from 1.41 to 2.07% at 0.1 μg/ml for the four enantiomer peaks. Detection limits observed for MA and AP enantiomers were 20 ng/ml and 50 ng/ml in the spectrum scanning mode, and 0.5 ng/ml and 1 ng/ml in the single ion monitoring (SIM) mode, respectively. The HPLC/ESI-MS system studied here appeared highly sensitive and useful towards its forensic applications.
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- 1998
19. Determination of Methamphetamine and its Related Compounds Using Fourier Transform Raman Spectroscopy
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Michiaki Tatsuno, Chris Petty, Etsuo Nishio, Akishi Nara, Hitoshi Tsuchihashi, Hiroshi Nishioka, Mayumi Nishikawa, and Munehiro Katagi
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Detection limit ,Polypropylene ,010401 analytical chemistry ,Analytical chemistry ,Polyethylene ,01 natural sciences ,0104 chemical sciences ,010309 optics ,Methamphetamine Hydrochloride ,chemistry.chemical_compound ,symbols.namesake ,chemistry ,0103 physical sciences ,symbols ,Sample preparation ,Fourier transform infrared spectroscopy ,Spectroscopy ,Raman spectroscopy ,Instrumentation - Abstract
Fourier transform Raman spectroscopy (FT-Raman) is investigated as a simple and rapid method for the determination of the abused drug methamphetamine and its related compounds. Compounds can be reliably identified by using measurements made nondestructively and without the need for any sample preparation in around 1 min. The Raman spectrum of methamphetamine hydrochloride (MA) shows clear differences in spectra from a range of its related compounds such as amphetamine sulfate and ephedrine hydrochloride. These differences are adequate for spectral differentiation of the compounds. With the use of the FT-Raman technique, MA is also reliably identifiable to a detection limit of 1% (w/w) diluted in sodium chloride or water. FT-Raman spectra of MA were recorded through plastic packaging (polyethylene or polypropylene bags) typical of that used either by criminals for transportation or by law enforcement for containing and sealing evidence. Measurements could be made directly without removing the drug from the bag; excellent-quality spectra could be obtained with very little perturbation by the plastic bag.
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- 1997
20. Determination of the main hydrolysis products of organophosphorus nerve agents, methylphosphonic acids, in human serum by indirect photometric detection ion chromatography
- Author
-
Michiaki Tatsuno, Hitoshi Tsuchihashi, Mayumi Nishikawa, and Munehiro Katagi
- Subjects
Detection limit ,Sarin ,Chromatography ,Elution ,Hydrolysis ,Ion chromatography ,Reproducibility of Results ,General Chemistry ,Sensitivity and Specificity ,chemistry.chemical_compound ,Organophosphorus Compounds ,Column chromatography ,chemistry ,Humans ,Sample preparation ,Chemical Warfare Agents ,Methylphosphonic acid ,Chromatography, Liquid ,EMPA - Abstract
For the verification of the use of chemical warfare agents (CWA), sarin, soman and VX, a simple rapid and accurate method which allows us to simultaneously determine their degradation products, isopropyl methylphosphonic acid (IPMPA), pinacolyl methylphosphonic acid (PMPA), ethyl methylphosphonic acid (EMPA) and methylphosphonic acid (MPA), in human serum, was explored by indirect photometric detection ion chromatography (IPD-IC) which employs an anion-exchange column. IC analysis was performed after sample preparation with an Ag+-form cation-exchange resin cartridge, and the four methylphosphonic acids could be separated well. The proposed conditions are as follows: eluent, 0.5 mM phthalic acid-0.1 mM Tris (hydroxymethyl) aminomethane-5% acetonitrile; flow-rate, 1.0 ml/min; temperature, 50 degrees C; UV detector, 266 nm. All four methylphosphonic acids were eluted within 30 min with hardly any disturbance by impurities in the serum. Linear calibration curves were obtained for MPA, EMPA and IPMPA in the concentration range from 50 ng/ml to 1 microg/ml and for PMPA from 100 ng/ml to 1 microg/ml. The relative standard deviation for the methylphosphonic acids ranged from 3.8 to 6.9% at 500 ng/ml and the detection limits were 40 ng/ml for MPA, EMPA and IPMPA and 80 ng/ml for PMPA. The method would be suitable for analysis of human serum samples.
- Published
- 1997
21. Determination of the main hydrolysis product of O-ethylS-2-diisopropylaminoethyl methylphosphonothiolate, ethyl methylphosphonic acid, in human serum
- Author
-
Michiaki Tatsuno, Hitoshi Tsuchihashi, Mayumi Nishikawa, and Munehiro Katagi
- Subjects
Detection limit ,Chromatography ,Hydrolysis ,Reproducibility of Results ,Organothiophosphorus Compounds ,General Chemistry ,Sensitivity and Specificity ,Chloride ,Gas Chromatography-Mass Spectrometry ,chemistry.chemical_compound ,Organophosphorus Compounds ,chemistry ,medicine ,Humans ,Indicators and Reagents ,Organosilicon Compounds ,Cholinesterase Inhibitors ,Gas chromatography ,Derivatization ,Acetonitrile ,Quantitative analysis (chemistry) ,EMPA ,medicine.drug - Abstract
For the unequivocal proof of the use of a nerve agent O-ethyl S-2-diisopropylaminoethyl methylphosphonothiolate (VX), a rapid, accurate and sensitive method which allows us to identify its main hydrolysis product ethyl methylphosphonic acid (EMPA) in human serum was explored by GC-MS. GC-MS analysis was performed after solvent extraction with acetonitrile in acidic conditions from the serum sample, which was previously deproteinized by micro-ultrafiltration, and subsequent tert.-butyldimethylsilyl derivatization with N-methyl-N-(tert.-butyldimethylsilyl)trifluoroacetamide (MTBSTFA) with 1% tert.-butyldimethylsilyl chloride (t-BDMSC). Linear calibration curves were obtained in the concentration range from 50 to 500 ng/ml for EMPA in the full-scan EI mode and from 5 to 50 ng/ml for EMPA in the SIM EI mode. The relative standard deviation obtained at a sample concentration of 50 ng/ml was 8.4% in the full-scan mode and 7.3% in the SIM mode. Upon applying the full-scan EI and CI mode, 40 ng/ml and 80 ng/ml were the detection limits. Using the SIM-EI mode, in which the ion at m/z 153 was chosen, the limit was 3 ng/ml.
- Published
- 1997
22. Detection of Internal and External Methamphetamine in Human Hair by Ion Mobility Spectrometry
- Author
-
Hitoshi Tsuchihashi, Michiaki Tatsuno, Mayumi Nishikawa, Munehiro Katagi, Prisca Regenscheit, Akihiro Miki, Thomas Keller, Lena Kim, Werner Bernhard, and Shigekazu Hatano
- Subjects
Detection limit ,Chromatography ,integumentary system ,Ion-mobility spectrometry ,Chemistry ,otorhinolaryngologic diseases ,Sample preparation ,sense organs ,Toxicology - Abstract
Internal and external methamphetamine (MA) was detected from human hair using ion mobility spectrometry (IMS). Direct IMS monitoring without any sample preparation proved to be effective only to detect MA from externally contaminated hair. The detection limit of external MA was 0.5 ng/mg by direct IMS monitoring when the sample amount was 1.0 mg. To detect MA incorporated in the hair, the authors measured MA users' hair samples by IMS after pulverization or digestion. Pulverized samples gave only moderate sensitivity for the detection of MA in the hair. Digestion of the hair sample with 5 M NaOH (methanol-water, 4 : 1) prior to IMS measurement was very effective to identify MA incorporated in the hair, and the drug was semi-quantitatively detected by this method. The detection limit of MA was 0.5 ng/mg with 2.0 mg of hair sample. Using a combination of the digestion method and direct IMS monitoring, the authors were able to distinguish between MA externally contaminating hair and MA incorporated in a user's hair. It was demonstrated using MA users' hair samples that the results obtained by the digestion method were in good agreement with the GC-MS results. Our method was also successfully applied to a limited amount of MA user's hair sample.
- Published
- 1997
23. Metabolic profiling of urine and blood plasma in rat models of drug addiction on the basis of morphine, methamphetamine, and cocaine-induced conditioned place preference
- Author
-
Akira Ishii, Takako Sato, Takeshi Bamba, Kei Zaitsu, Michiaki Tatsuno, Koichi Suzuki, Hitoshi Tsuchihashi, Kiyoko Bando, Noriaki Shima, Izuru Miyawaki, Eiichiro Fukusaki, Hiroshi Horie, and Munehiro Katagi
- Subjects
Male ,Narcotics ,Substance-Related Disorders ,media_common.quotation_subject ,Pharmacology ,Biochemistry ,Gas Chromatography-Mass Spectrometry ,Analytical Chemistry ,Methamphetamine ,Rats, Sprague-Dawley ,chemistry.chemical_compound ,Metabolomics ,Cocaine ,Reward ,mental disorders ,Blood plasma ,polycyclic compounds ,medicine ,Animals ,media_common ,Morphine ,Chemistry ,Addiction ,Conditioned place preference ,Rats ,Spermidine ,Disease Models, Animal ,nervous system ,Metabolome ,Conditioning, Operant ,Brain stimulation reward ,Metabolic Networks and Pathways ,medicine.drug - Abstract
The metabolic profiles of urine and blood plasma in drug-addicted rat models based on morphine (MOR), methamphetamine (MA), and cocaine (COC)-induced conditioned place preference (CPP) were investigated. Rewarding effects induced by each drug were assessed by use of the CPP model. A mass spectrometry (MS)-based metabolomics approach was applied to urine and plasma of MOR, MA, and COC-addicted rats. In total, 57 metabolites in plasma and 70 metabolites in urine were identified by gas chromatography-MS. The metabolomics approach revealed that amounts of some metabolites, including tricarboxylic acid cycle intermediates, significantly changed in the urine of MOR-addicted rats. This result indicated that disruption of energy metabolism is deeply relevant to MOR addiction. In addition, 3-hydroxybutyric acid, L-tryptophan, cystine, and n-propylamine levels were significantly changed in the plasma of MOR-addicted rats. Lactose, spermidine, and stearic acid levels were significantly changed in the urine of MA-addicted rats. Threonine, cystine, and spermidine levels were significantly increased in the plasma of COC-addicted rats. In conclusion, differences in the metabolic profiles were suggestive of different biological states of MOR, MA, and COC addiction; these may be attributed to the different actions of the drugs on the brain reward circuitry and the resulting adaptation. In addition, the results showed possibility of predict the extent of MOR addiction by metabolic profiling. This is the first study to apply metabolomics to CPP models of drug addiction, and we demonstrated that metabolomics can be a multilateral approach to investigating the mechanism of drug addiction.
- Published
- 2013
24. Development of a simple one-pot extraction method for various drugs and metabolites of forensic interest in blood by modifying the QuEChERS method
- Author
-
Keiko Nakanishi, Hitoshi Tsuchihashi, Koichi Suzuki, Akihiro Miki, Tooru Kamata, Shuntaro Matsuta, Noriaki Shima, Hiroshi Nishioka, Kei Zaitsu, Michiaki Tatsuno, Munehiro Katagi, and Kento Tsuboi
- Subjects
Analyte ,Acetonitriles ,Metabolite ,Sodium Chloride ,Quechers ,Gas Chromatography-Mass Spectrometry ,Pathology and Forensic Medicine ,chemistry.chemical_compound ,Forensic Toxicology ,Magnesium Sulfate ,Liquid chromatography–mass spectrometry ,medicine ,Humans ,Desiccation ,Blood Coagulation ,Whole blood ,Acetic Acid ,Chromatography ,Chemistry ,Brotizolam ,Extraction (chemistry) ,Solid Phase Extraction ,Pharmaceutical Preparations ,Solvents ,Indicators and Reagents ,Gas chromatography–mass spectrometry ,Law ,medicine.drug ,Chromatography, Liquid - Abstract
A rapid and convenient extraction method has been developed for the determination of various drugs and metabolites of forensic interest in blood by modifying the dispersive solid-phase extraction method "QuEChERS". The following 13 analytes with various chemical properties were used for the method development and its validation: amphetamine, methamphetamine, zolpidem, the carboxylate-form major metabolite of zolpidem M-1, flunitrazepam, 7-aminoflunitrazepam, phenobarbital, triazolam, α-hydroxytriazolam, brotizolam, α-hydroxybrotizolam, chlorpromazine, and promethazine. The modification of the QuEChERS method includes the use of relatively large amounts of inorganic salts in order to coagulate blood, which allows easy isolation of the organic extract phase. A combination of 100 mg anhydrous magnesium sulfate as a dehydrating agent, 50mg sodium chloride as a salting-out agent, and 500 μL acetonitrile containing 0.2% acetic acid as the organic solvent provided the optimum conditions for processing a 100 μL whole blood sample. The recoveries of the analytes spiked into whole blood at 0.5 μg/mL ranged between 59% and 93%. Although the addition of the graphitized carbon Envi-carb for cleanup decreased the recoveries of zolpidem and its carboxylate-form metabolite M-1, it was very effective in avoiding interferences by cholesterol. The present method can provide a rapid, effective, user-friendly, and relatively hygienic method for the simultaneous extraction of a wide range of drugs and metabolites in whole blood specimens.
- Published
- 2013
25. Determination of Malathion Metabolites in Biological Samples by LC/MS
- Author
-
Munehiro Katagi, Hitoshi Tsuchihashi, and Michiaki Tatsuno
- Subjects
chemistry.chemical_compound ,Acetic acid ,Chromatography ,Column chromatography ,chemistry ,Malaoxon ,Liquid chromatography–mass spectrometry ,Metabolite ,Malathion ,Thermospray ,Toxicology ,Ammonium acetate - Abstract
The procedure for the determination of the main metabolites of malathion (MA), malaoxon (MO), malathion dicarboxylic acid (DCA), malathion α-, β-monocarboxylic acid (α-, β-MCA), desmethyl malathion (DM-MA), in addition to unchanged MA was investigated using positive-ion mode thermospray liquid chromatography-mass spectrometry (TSP-LC/MS). Following the solid-phase extraction of the sample at pH 2 using Sep-Pak C18 cartridge with methanol as eluent, the extract was analyzed on TSP-LC/MS. LC analyses were performed on C18-bonded phase using methanol-100 mM ammonium acetate (60 : 40 v/v, pH 3.65 with trifluoro acetic acid) as eluent at a flow rate of 1.0 ml/min. Every mass spectrum of MA and its metabolites provided both the protonated molecular ion [M+H]+ and the ammonium adduct ion [M+NH4]+. By the solid-phase extraction, they were recovered relatively well, and the detection limits were ranged from 0.2 μg/ml to 2.5 μg/ml by scan mode, ranged from 5 ng/ml to 200 ng/ml by selected ion monitering (SIM) mode. In the urine sample, the coefficients of variations for the prepared method by SIM mode were ranged from 3.3% to 7.2% at 500 ng/ml level of each metabolite. For a blood sample of a female, who had committed suicide by taking MA, TSP-LC/MS analysis were attemped following the prepared method, the metabolites such as α-MCA were detected, and it was possible to prove that she had taken MA.
- Published
- 1994
26. The Analysis of Quaternary Ammonium Compounds in Human Urine by Thermospray Liquid Chromatography-Mass Spectrometry
- Author
-
Hitoshi Tsuchihashi, Mayumi Nishikawa, Fumiyo Kasuya, Kazuo Igarashi, Miyoshi Fukui, and Michiaki Tatsuno
- Subjects
Distigmine ,Detection limit ,Chromatography ,Chemistry ,Thermospray ,Toxicology ,Mass spectrometry ,chemistry.chemical_compound ,Liquid chromatography–mass spectrometry ,Bromothymol blue ,medicine ,Selected ion monitoring ,Ammonium ,medicine.drug - Abstract
A simple and rapid method for the detection of 12 quaternary ammonium compounds (Suxamethonium, Pancuronium, Benzethonium, Acetylcholine, Bethanechol, Hexamethonium, Propantheline, Methylbenactyzium, Neostigmine, Distigmine, Pyridostigmine and Ambenonium) using thermospray high-performance liquid chromatography (LC)-mass spectrometry was investigated. Each compound was extracted from urine as an ion-pair with bromothymol blue, tropaeolin OO and hexanitrodiphenilamine in dichloromethane. The used LC column was Asahipak GS-320H for aqueous steric exclusion chromatography, and the mobile phase was 100 mM ammonium acetate-acetonitrile (90/10 v/v or 70/30 v/v). The ion source block and tip heater temperatures were set at 300 and 320°C, respectively. The vaporizer control temperature was kept at the temperature of the take off temperature minus 15°C. The recoveries of 12 quaternary ammonium compounds from the spiked urine were 76.1 to 98.6% by ion-pair extraction. The detection limits of these compounds for the simultaneous analysis were 0.5-80 ng/ml by selected ion monitoring mode.
- Published
- 1994
27. Cross-reactivities of various phenethylamine-type designer drugs to immunoassays for amphetamines, with special attention to the evaluation of the one-step urine drug test Instant-View™, and the Emit® assays for use in drug enforcement
- Author
-
Kei Zaitsu, Koichi Suzuki, Keiko Nakanishi, Hitoshi Tsuchihashi, Noriaki Shima, Munehiro Katagi, Akihiro Miki, Michiaki Tatsuno, Hiroe Kamata, and Tooru Kamata
- Subjects
Drug ,Adult ,Male ,Phenethylamine ,Adolescent ,medicine.drug_class ,media_common.quotation_subject ,Amphetamine-Related Disorders ,Pharmacology ,Pathology and Forensic Medicine ,Designer Drugs ,chemistry.chemical_compound ,Forensic Toxicology ,Young Adult ,Enzyme Multiplied Immunoassay Technique ,Phenethylamines ,medicine ,Drug test ,Humans ,Amphetamine ,Child ,media_common ,Aged ,medicine.diagnostic_test ,Chemistry ,Amphetamines ,MDMA ,Methamphetamine ,Middle Aged ,Designer drug ,Substance Abuse Detection ,Immunoassay ,Central Nervous System Stimulants ,Female ,Law ,medicine.drug - Abstract
Cross-reactivities of 76 kinds of phenethylamine-type designer drugs and related compounds to the urine drug tests Instant-View ™ (IV) (the Methamphetamine (MA) test, the Amphetamine 300 test, and the MDMA test) have been investigated. An on-site urine test kit consisting of these three IV tests has been evaluated for the on-site screening of MA users, and the kit has been found to have satisfactory specificity for drug enforcement purposes by separately detecting both MA and its metabolite amphetamine. The cross-reactivity profiles of Emit® II Plus Amphetamines Assay, Emit® II Plus Ecstasy assay, and Emit® d.a.u.® Amphetamine Class assay have also been investigated and discussed.
- Published
- 2011
28. The analysis of quaternary ammonium compounds by pyrolysis gas chromatography/mass spectrometry and thin-layer chromatography
- Author
-
Hitoshi Tsuchihashi, Michiaki Tatsuno, and Mayumi Nishikawa
- Subjects
Pyrolysis–gas chromatography–mass spectrometry ,Chromatography ,Aqueous normal-phase chromatography ,Chemistry ,Gas chromatography ,Toxicology ,High-performance liquid chromatography ,Ammonium compounds ,Sample preparation in mass spectrometry ,Thin-layer chromatography - Published
- 1990
29. Pulsed terahertz spectroscopy and imaging applied to inspection of explosives and inflammable liquids
- Author
-
Masanori Hangyo, Masahiko Tani, Kenji Koide, Takeshi Ikeda, Michiaki Tatsuno, Akira Matsushita, Mariko Yamaguchi, Fumiaki Miyamaru, Yukio Manami, and Kohji Yamamoto
- Subjects
boats ,Materials science ,Explosive material ,business.industry ,Terahertz radiation ,Plastic bottle ,Optoelectronics ,business ,boats.hull_material ,Terahertz spectroscopy and technology - Abstract
We carried out applied researches on the pulsed terahertz spectroscopy and the terahertz imaging to detect the C-4 explosive hidden in a mail and inflammable liquids stored in plastic bottles. We confirm that THz techniques are quite efficient at contactless and nondestructive inspection of hazardous materials used in terrorist activities.
- Published
- 2005
30. Application of High-Performance Liquid Chromatography/Mass Spectrometry to Drug Screening
- Author
-
Hitoshi Tsuchihashi, Hiroshi Kogawa, Toyoji Higuchi, Masaomi Satoh, and Michiaki Tatsuno
- Subjects
Male ,Drug ,Chromatography ,Chemistry ,media_common.quotation_subject ,Human bone ,Forensic Medicine ,Mass spectrometry ,High-performance liquid chromatography ,Mass Spectrometry ,Pathology and Forensic Medicine ,Bone Marrow ,Liquid chromatography–mass spectrometry ,Humans ,Bromisovalum ,Chromatography, High Pressure Liquid ,media_common - Abstract
High-performance liquid chromatography/mass spectrometry enabled us not only to measure bromvalerylurea rapidly, < or = 2 h following accumulation of human bone marrow, but also to improve sensitivity without interference. The method can be widely and effectively used in the fields of pharmacy and forensic sciences.
- Published
- 1996
31. Urinary excretion of selegiline N-oxide, a new indicator for selegiline administration in man
- Author
-
Hitoshi Tsuchihashi, H Tsutsumi, Mayumi Nishikawa, Akihiro Miki, Michiaki Tatsuno, K. Nakajima, Munehiro Katagi, Hiroshi Nishioka, and Tooru Kamata
- Subjects
Adult ,medicine.medical_specialty ,Spectrometry, Mass, Electrospray Ionization ,Monoamine Oxidase Inhibitors ,Time Factors ,Health, Toxicology and Mutagenesis ,Metabolite ,Pharmacology ,Toxicology ,Biochemistry ,Methamphetamine ,Excretion ,chemistry.chemical_compound ,Pharmacokinetics ,Oral administration ,Internal medicine ,Selegiline ,medicine ,Humans ,Amphetamine ,Chromatography, High Pressure Liquid ,Adrenergic Uptake Inhibitors ,Dose-Response Relationship, Drug ,Amphetamines ,General Medicine ,Hydrogen-Ion Concentration ,Dose–response relationship ,Endocrinology ,chemistry ,Models, Chemical ,medicine.drug - Abstract
1. The metabolism of selegiline (SG) has been studied by investigating the time-course of urinary excretion of SG and its metabolites using high-performance liquid chromatography-electrospray ionization mass spectrometry (LC-ESI MS) in combination with solid-phase extraction. 2. The excretion profiles of SG and its four major metabolites, selegiline-N-oxide (SGO), N-desmethylselegiline (DM-SG), methamphetamine (MA) and amphetamine (AP), were investigated in six healthy volunteers after oral administrations of SG hydrochloride in a single dose of 2.5 or 7.5mg, and a repeat twice-daily dose of 5.0 mg day(-1) (for 3 days). 3. The cumulative amount of SGO excreted within approximately the first 8-12h was comparable with MA, and the amount in the first 72 h was 2.0-7.8 times larger (2.8-13.2% of the dose) than that of DM-SG. 4. These results demonstrate that SGO can be used in place of DM-SG, which is known to be a main specific metabolite of SG, as a new indicator for the discrimination of SG use compared with MA abuse.
- Published
- 2002
32. Determination of Metabolites of Nerve Agent O-Ethyl-S-2-Diisopropylaminoethyl Methylphosphonothioate (VX)
- Author
-
Michiaki Tatsuno, Hitoshi Tsuchihashi, Mayumi Nishikawa, M. Katagi, and Akihiro Miki
- Subjects
Chromatography ,Chemistry ,medicine ,Nerve agent ,medicine.drug - Published
- 1999
33. On-line solid-phase extraction liquid chromatography-continuous flow frit fast atom bombardment mass spectrometric and tandem mass spectrometric determination of hydrolysis products of nerve agents alkyl methylphosphonic acids by p-bromophenacyl derivatization
- Author
-
Hitoshi Tsuchihashi, Munehiro Katagi, Mayumi Nishikawa, and Michiaki Tatsuno
- Subjects
Detection limit ,Chromatography ,Chemistry ,Hydrolysis ,Organic Chemistry ,Soman ,Organophosphonates ,Water ,General Medicine ,Fast atom bombardment ,Spectrometry, Mass, Fast Atom Bombardment ,Mass spectrometry ,Biochemistry ,High-performance liquid chromatography ,Sensitivity and Specificity ,Analytical Chemistry ,chemistry.chemical_compound ,Blood serum ,Organophosphorus Compounds ,Humans ,Selected ion monitoring ,Solid phase extraction ,Chemical Warfare Agents ,Derivatization ,Chromatography, High Pressure Liquid - Abstract
For proof of the presence of chemical warfare agents sarin, soman and VX, a rapid, accurate and sensitive method which allows us to determine their hydrolysis products ethyl methylphosphonic acid, isopropyl methylphosphonic acid and pinacolyl methyl phosphonic acid was explored by using continuous flow frit fast atom bombardment (FAB) LC-MS and LC-MS-MS. After derivatization of analytes with p-bromophenacyl bromide, LC-MS-MS analyses for screening were performed by a flow injection method. The three alkyl methylphosphonic acids (AMPAs) were eluted within 5 min, and the detection limits for the three AMPAs ranged from 1 to 5 ng/ml. For confirmation of the screening results, LC-MS-MS analysis with chromatographic separation was conducted by using a narrow bore column. The three AMPAs were all eluted with excellent separation within 25 min, and the detection limits ranged from 1 to 20 ng/ml. Quantitative measurement was performed by LC-MS in selected ion monitoring (SIM) mode with chromatographic separation. Linear calibration curves were obtained for the three AMPAs and the detection limits ranged from 0.5 to 3 ng/ml. The relative standard deviation for peak area ranged from 3.4 to 6.0% at 50 ng/ml for the three AMPAs.
- Published
- 1999
34. Identification of metabolites of nerve agent VX in serum collected from a victim
- Author
-
Hitoshi Tsuchihashi, Mayumi Nishikawa, Munehiro Katagi, and Michiaki Tatsuno
- Subjects
Adult ,Male ,Health, Toxicology and Mutagenesis ,Metabolite ,Toxicology ,Mass spectrometry ,Gas Chromatography-Mass Spectrometry ,Analytical Chemistry ,chemistry.chemical_compound ,Blood serum ,medicine ,Environmental Chemistry ,Humans ,Sample preparation ,Chemical Warfare Agents ,Derivatization ,Nerve agent ,Chemical ionization ,Methylene Chloride ,Chemical Health and Safety ,Chromatography ,biology ,Organothiophosphorus Compounds ,chemistry ,Enzyme inhibitor ,biology.protein ,Cholinesterase Inhibitors ,medicine.drug - Abstract
A human serum sample collected from a victim of the Osaka VX incident was analyzed according to our developed technique for metabolites of VX. Gas chromatography-mass spectrometry (GC-MS) in full-scan electron impact and chemical ionization modes were used, and, for more reliable confirmation, GC-MS-MS was also employed. In the serum sample, both ethyl methylphosphonic acid and 2-(diisopropylamino-ethyl)methyl sulfide were detected. These results indicated that the techniques using GC-MS and GC-MS-MS were applicable to biological samples such as serum. These results also provide the first documented, unequivocal identification of the specific metabolites of VX in victim's serum and, furthermore, clarify a part of the metabolic pathway of VX in the human body.
- Published
- 1998
35. Application of ion mobility spectrometry to the rapid screening of methamphetamine incorporated in hair
- Author
-
Thomas Keller, Mayumi Nishikawa, Munehiro Katagi, Priska Regenscheit, Akihiro Miki, Michiaki Tatsuno, Hitoshi Tsuchihashi, and Richard Dirnhofer
- Subjects
Detection limit ,Chromatography ,integumentary system ,Ion-mobility spectrometry ,Chemistry ,Spectrum Analysis ,Reproducibility of Results ,General Chemistry ,Reference Standards ,Mass spectrometry ,Metanfetamina ,Metamfetamine ,Methamphetamine ,Substance Abuse Detection ,Investigation methods ,otorhinolaryngologic diseases ,Humans ,sense organs ,Gas chromatography ,Quantitative analysis (chemistry) ,Hair - Abstract
Using ion mobility spectrometry (IMS), a simple, sensitive and rapid screening for methamphetamine (MA) incorporated in user's hair has been developed. To completely unbind MA from hair matrix and to achieve its effective vaporization for the IMS detection, the hair sample was digested in 5 M NaOH (methanol-water, 4:1, v/v) solution prior to IMS measurement. MA in hair was semi-quantitatively detected by monitoring the digested hair sample employing dibenzylamine (DBA) as internal standard. The minimum amount of hair sample required was 2 mg and its digested sample was ample for four IMS measurements. The detection limit of MA in hair was 0.5 ng mg(-1). This proposed method was applicable to the semi-quantitative detection of MA in users' hair samples, and to the sectional analysis for MA in a limited amount of user's hair. The IMS results obtained were in good agreement with their GC-MS determination.
- Published
- 1997
36. Simultaneous determination of illicit drugs in human urine by liquid chromatography-mass spectrometry
- Author
-
Hitoshi Tsuchihashi, Mayumi Nishikawa, Munehiro Katagi, and Michiaki Tatsuno
- Subjects
Chemical Health and Safety ,Chromatography ,Illicit Drugs ,Health, Toxicology and Mutagenesis ,Temperature ,Methylephedrine ,Thermospray ,Urinalysis ,Toxicology ,High-performance liquid chromatography ,Sensitivity and Specificity ,Mass Spectrometry ,Analytical Chemistry ,chemistry.chemical_compound ,chemistry ,Liquid chromatography–mass spectrometry ,medicine ,Benzoylecgonine ,Environmental Chemistry ,Humans ,Selected ion monitoring ,Ephedrine ,Ammonium acetate ,medicine.drug ,Chromatography, Liquid - Abstract
The method for simultaneous determination and confirmation of illicit drugs (e.g., methamphetamine, amphetamine, ephedrine, methylephedrine, morphine, morphine-3-glucuronide, morphine-6-glucuronide, 6-acetylmorphine, cocaine, and benzoylecgonine) in human urine by thermospray liquid chromatography-mass spectrometry (LC-MS) was studied. The LC-MS separation was performed on a reversed phase column (L-column ODS; 150 mm x 4.6-mm i.d.) using a gradient mobile phase system of 100mM ammonium acetate for 1 min then linear ramps to 100mM ammonium acetate including 40% acetonitrile at 20 min. Extraction was conducted by solid-phase extraction using a Sep-pak C18 cartridge. The drugs were eluted with 2 mliters of 40% acetonitrile in 100 mM ammonium acetate, pH3 (adjusted with acetic acid), from the cartridge. A 50-microL volume of the eluate was injected into the LC-MS. The recoveries by this extraction were 88 to 99%. The mass spectra of methamphetamine, amphetamine, ephedrine, methylephedrine, morphine, 6-acetylmorphine, cocaine, and benzoylecgonine showed the quasi-molecular [M + H]+ ion as the base peak, whereas morphine-3-glucuronide and morphine-6-glucuronide showed [MH-glucuronide]+ ion as the base peak. The calibration graphs were linear and reproducible. Detection limits of these drugs ranged from 2 to 40 ng/mliters by selected ion monitoring (SIM) mode and from 50 to 400 ng/mliters by scan mode. The coefficients of variation for the analysis of these drugs ranged from 4.5 to 9.5% at a concentration of 0.4 micrograms/mliters (n = 10).
- Published
- 1996
37. Erratum:Comprehensive Analytical Methods of the Synthetic Cannabinoids Appearing In the Illicit Drug Market
- Author
-
Kei Zaitsu, Munehiro Katagi, Keiko Nakanishi, Noriaki Shima, Hiroe Kamata, Tooru Kamata, Hiroshi Nishioka, Akihiro Miki, Michiaki Tatsuno, Tatsunori Iwamura, Takako Sato, Hitoshi Tsuchihashi, and Koichi Suzuki
- Published
- 2012
38. The analysis of cocaine and its metabolites by liquid chromatography/atmospheric pressure chemical ionization-mass spectrometry (LC/APCI-MS)
- Author
-
Hitoshi Tsuchihashi, Kazuo Igarashi, Miyoshi Fukui, Mayumi Nishikawa, Michiaki Tatsuno, Fumiyo Kasuya, and K. Nakajima
- Subjects
Chemical ionization ,Chromatography ,Reproducibility of Results ,Spectrometry, Mass, Secondary Ion ,Atmospheric-pressure chemical ionization ,Forensic Medicine ,Mass spectrometry ,High-performance liquid chromatography ,Sensitivity and Specificity ,Pathology and Forensic Medicine ,Norcocaine ,Substance Abuse Detection ,chemistry.chemical_compound ,chemistry ,Cocaine ,Liquid chromatography–mass spectrometry ,Evaluation Studies as Topic ,Benzoylecgonine ,Humans ,Ecgonine ,Law ,Chromatography, High Pressure Liquid - Abstract
The method for simultaneous determination of cocaine and its four metabolites (benzoylecgonine, ecgonine methyl ester, ecgonine and norcocaine) in urine by liquid chromatography/atmospheric pressure chemical ionization-mass spectrometry (LC/APCI-MS) was studied. The mass spectra showed the quasi-molecular ions, [M+H]+ as the base peak. LC/APCI-MS analysis was performed by focusing the characteristic ions at m/ = 186, 290, 200, 304 and 290 for ecgonine, benzoylecgonine, ecgonine methyl ester, cocaine and norcocaine, respectively. Cocaine and its four metabolites were well separated by high performance liquid chromatography (HPLC). The recoveries of cocaine and its metabolites from the spiked urine were 40.3-94.7% by solid-phase extraction with two type cartridges (Bond Elut Certify and Bond Elut SCX).
- Published
- 1994
39. Discrimination of Inflammable Liquids by Two-Dimensional Mapping of Complex Refractive Indices in the Terahertz Range
- Author
-
Takeshi Ikeda, Mariko Yamaguchi, Kohji Yamamoto, Michiaki Tatsuno, Yukio Minami, Masanori Hangyo, Masahiko Tani, and Akira Matsushita
- Subjects
Chemistry ,Terahertz radiation ,business.industry ,Quantitative Biology::Tissues and Organs ,General Engineering ,Physics::Optics ,General Physics and Astronomy ,Refraction ,Quantitative Biology::Cell Behavior ,symbols.namesake ,Amplitude ,Fourier transform ,Optics ,Attenuation coefficient ,symbols ,Transmittance ,Absorption (electromagnetic radiation) ,business ,Refractive index - Abstract
Terahertz time-domain spectroscopy has been applied to the discrimination of inflammable liquids. Indices of refraction and absorption coefficients of some inflammable liquids reflect those of their ingredients, such as alkanes and aromatic hydrocarbons. The inflammable liquids can be distinguished from each other by plotting their values on a two-dimensional map, in which two axes are the index of refraction and absorption coefficient at 30 cm-1. We also plotted the values of the inflammable liquids on a two-dimensional map, in which two axes are the amplitude transmittance and optical delay at the peak of the terahertz waveform. It demonstrates that the discrimination of inflammable liquids is possible without Fourier transformation of the terahertz waveform.
- Published
- 2010
40. Analysis of methylbenactyzium bromide in human urine by thin-layer chromatography and pyrolysis gas chromatography
- Author
-
Michiaki Tatsuno, Hitoshi Tsuchihashi, S. Suzuki, and Mayumi Nishikawa
- Subjects
Detection limit ,Chromatography ,Hot Temperature ,Calibration curve ,Chemistry ,Silica gel ,Mass spectrometry ,Thin-layer chromatography ,Gas Chromatography-Mass Spectrometry ,Pathology and Forensic Medicine ,Quaternary Ammonium Compounds ,chemistry.chemical_compound ,Bromide ,Calibration ,Humans ,Gas chromatography ,Chromatography, Thin Layer ,Law ,Pyrolysis - Abstract
A rapid and simple method of utilizing thin-layer chromatography (TLC) and pyrolysis gas chromatography (PyGC) for the identification and determination of methylbenactyzium bromide in human urine was studied in this report. Methylbenactyzium bromide was extracted from urine with ODS-cartridge (Sep-Pak C18), then spotted onto a silica gel 60 F254 TLC plate. After development, the separated spot of methylbenactyzium bromide was scraped and wrapped with a ferromagnetic foil without extraction by any organic solvents. The sample was applied into PyGC analysis. The optimum temperature for pyrolysis was 590 degrees C. The main degradation product of methylbenactyzium bromide was identified as diphenylmethane in this procedure by gas chromatography/mass spectrometry (GC/MS). A calibration graph prepared by absolute calibration method showed a good linearity over the concentration range of 1-75 micrograms/spot for methylbenactyzium bromide. The coefficient of variation obtained for eleven replicate analyses of the 3 micrograms/spot of standard methylbenactyzium bromide was 3.8%. The detection limit of this compound by this procedure was 0.1 micrograms/spot.
- Published
- 1991
41. Investigation of inflammable liquids by terahertz spectroscopy
- Author
-
Kohji Yamamoto, Yukio Minami, Masanori Hangyo, Takeshi Ikeda, Mariko Yamaguchi, Akira Matsushita, Masahiko Tani, and Michiaki Tatsuno
- Subjects
Optics ,Materials science ,Physics and Astronomy (miscellaneous) ,business.industry ,Terahertz radiation ,Nondestructive testing ,Screening method ,business ,Terahertz spectroscopy and technology - Abstract
We have examined a nondestructive and contactless screening method for water and inflammable liquids stored in common beverage plastic bottles by the terahertz time-domain spectroscopy. No THz transmission has been observed between 10 and 60cm−1 for 45-mm-thick water in plastic bottles. Part of the THz wave, on the other hand, has been transmitted through the commercially available inflammable liquids in the same bottles. The differences in the absorption intensities and the refractive indices in the THz region, which reflect the ingredients of organic compounds, allow us to distinguish these inflammable liquids. We confirm that the screening method based on the THz transmission can be applied to classifying the commercially available inflammable liquids stored in plastic bottles and to distinguishing these inflammable liquids from water as well.
- Published
- 2005
42. Determination of degradation products and the time-course of diazinon and dichlorvos in aqueous and hydrochloric acid solution
- Author
-
Michiaki Tatsuno and Hitoshi Tsuchihashi
- Subjects
chemistry.chemical_compound ,Diazinon ,Aqueous solution ,Chromatography ,chemistry ,Dichlorvos ,Degradation (geology) ,Hydrochloric acid ,Gas chromatography ,Toxicology ,Mass spectrometry ,Thin-layer chromatography - Abstract
Degradation products of diazinon and dichlorvos, organophosphorus pesticides, were investigated, and their degradation time-courses were also examined. The degradation of both compounds was carried out under the condition of static state in aqueous solution and hydrochloric acid solution (pH 2.0) at 37°C. By gas chromatography (GC), peaks of diazinon and dichlorvos were not observed in sample solutions after about 20 d. Degradation products of diazinon, and dichlorvos were identified to be 2-isopropyl-4-methyl-6-hydroxypyrimidine and dichloroacetaldehyde by gas chromatography-mass spectrometry (GC-MS), respectively. These degradation products were determined by thin layer chromatography, GC and (GC-MS).
- Published
- 1988
43. Retrieval system for drugs with dual fused silica capillary gas chromatography
- Author
-
Michiaki Tatsuno, Hirotaka Ono, and Hitoshi Tsuchihashi
- Subjects
Chromatography ,Chemistry ,Gas chromatography ,Toxicology ,Fused silica capillary - Published
- 1988
44. Simultaneous determination of paraquat and diquat utilizing those oxidation products by high performance liquid chromatography
- Author
-
Hitoshi Tsuchihashi, Kazuo Otsuki, and Michiaki Tatsuno
- Subjects
Detection limit ,chemistry.chemical_compound ,Potassium ferricyanide ,Chromatography ,chemistry ,Paraquat ,Silica gel ,Reagent ,Ferricyanide ,Toxicology ,Diquat ,High-performance liquid chromatography - Abstract
Method for the analysis of paraquat and diquat with those oxidation products were studied by high performance liquid chromatography (HPLC) and thin-layer chromatography (TLC). Paraquat and diquat were easily oxidized by potassium ferricyanide in alkaline solution, and the former formed 1, 1'-dimethyl-4, 4'-bipyridyl-2, 2'-dione [I], the latter formed 6, 7-dihydrodipyrido [1, 2-a : 2', 1'-c] pyrazine-4, 9-dione [II]. Oxidative reaction of paraquat and diquat has been carried out in the stirred suspension of 1%-potassium ferricyanide in 9 N-sodium hydroxide at room temperature over 1 min. These oxidation products were determined by HPLC using a reversed phase column packed with Shim-pack CLC-ODS (6.0 mm i.d.×0.15 m) and an ionpairing reagent as a mobile phase with a fluorescence spectroscopic detector. The mobile phase consisted of 0.001 M sodium 1-octanesulfonate in 10% acetonitrile-10 mM phosphate buffer (pH 2.6). The calibration curves gave a good linearity in the range of 0.1-10μg/ml on paraquat and 0.3-10μg/ml on diquat. These oxidation products were separated on silica gel thin-layer chromatogram with a solvent system consisting of chloroform-acetone-methanol (8 : 1 : 1). Rf values of I and II were 0.47 and 0.64, respectively. Detection limits of paraquat and diquat were 20 ng and 10 ng, respectively.
- Published
- 1988
45. Stopped-flow Measurement of Reaction Rate of Triose Reductone with 2,6-Dichlorophenolindophenol and Its Application to the Determination of Triose Reductone
- Author
-
Yasunori Nitta, Tai Tokuyama, Keitaro Hiromi, Michiaki Tatsuno, Masanosuke Takagi, and Hitoshi Obata
- Subjects
Reaction rate ,chemistry.chemical_compound ,Reaction rate constant ,chemistry ,Inorganic chemistry ,Ph range ,Organic chemistry ,Dichlorophenolindophenol ,Stopped flow ,General Agricultural and Biological Sciences ,General Biochemistry, Genetics and Molecular Biology ,Triose reductone - Abstract
The reduction of 2, 6-dichlorophenolindophenol by triose reductone was studied in a wide pH range (pH 2~11), using a stopped-flow apparatus. The apparent first-order rate constant, kapp, and the second-order rate constant, k, were obtained. The k-pH profile resembles that of l-ascorbic acid, though the rate of l-ascorbic acid is considerably larger than that of triose reductone. Determination of triose reductone by stopped-flow method is possible, even in the presence of various organic substances.
- Published
- 1979
46. Studies on the reduction of 2,6-dichlorophenolindophenol by aromatic amino reductones, using a stopped-flow method
- Author
-
Yasunori Nitta, Tai Tokuyama, Michiaki Tatsuno, Masanosuke Takagi, Hitoshi Obata, and Keitaro Hiromi
- Subjects
chemistry.chemical_compound ,Reaction rate constant ,Chemistry ,Organic chemistry ,Dichlorophenolindophenol ,General Agricultural and Biological Sciences ,Stopped flow ,Medicinal chemistry ,General Biochemistry, Genetics and Molecular Biology - Abstract
The reduction of 2, 6-dichlorophenolindophenol by aromatic amino reductones at pH 2.6 and 8.2 was investigated using stopped-flow method.1) Kinetic characteristics of the reductones are shown as the apparent first-order rate constant, kapp or the second-order rate constant, k. k-pH profile of five aromatic amino reductones showed a similar pattern to those of l-ascorbic acid.2) The log k of 2, 6-dichlorophenolindophenol reduction by aromatic amino reductones at pH 8.2 was found to linearly depend on Hammett’s σp value.
- Published
- 1979
Catalog
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