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Akamatsu S.,Hyogo Prefectural Institute of Public Health and Consumer science | Mitsuhashi T.,Hyogo Prefectural Institute of Public Health and Consumer science
Journal of Separation Science | Year: 2014

This study describes a method for the simultaneous determination of 12 synthetic cannabinoids by MEKC-MS/MS using a volatile surfactant (ammonium perfluorooctanoate) as a constituent of the micellar pseudostationary phase. Although most synthetic cannabinoids comigrated by a CZE method, sufficient separation could be achieved by the proposed method. The best separation was made possible by 50 mM ammonium perfluorooctanoate in 20% v/v acetonitrile/water (apparent pH* 9.0) as the BGE, followed by MS detection using a sheath liquid composed of 5 mM ammonium formate in 50% v/v methanol/water mixed hydro-organic solvent. The standard calibration curve for all analytes showed good linearity (r > 0.99). Satisfactory recoveries, ranging from 89.5 to 101.7%, were obtained. The LODs were 6.5-76.5 μg/g for the target analytes. This method appears to be a useful tool for the identification of synthetic cannabinoids in illegal herbal incense blends. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source


Akamatsu S.,Hyogo Prefectural Institute of Public Health and Consumer science | Mitsuhashi T.,Hyogo Prefectural Institute of Public Health and Consumer science
Journal of Food Composition and Analysis | Year: 2013

A simple capillary electrophoresis-tandem mass spectrometry (CE-MS/MS) method was developed for the analysis of free amino acids in commercial royal jelly (RJ) products containing various kinds of matrices. This method required no concentration step for sample preparation, and all 16 amino acids were determined without derivatization. The CE separation was achieved in an uncoated fused-silica capillary using a 1. M formic acid solution (pH 1.8) as the electrolyte, followed by MS/MS detection after mixing with a sheath liquid comprising 50% (v/v) methanol. The limits of detection (LODs) ranged from 0.61 to 10.5. μg (dry weight)/g for each amino acid. The recoveries for tablets, liquid drinks, and raw materials ranged from 88.3 to 108.6%, and the relative standard deviations (RSDs) were within 10%. The method was applied to 17 commercial RJ products, and the results were compared to those for honey. The relative proportions of free amino acids were specific for each RJ product, and the method was found to be useful in distinguishing not only among the different RJ products but also between RJ and honey. © 2013 Elsevier Inc. Source


Akamatsu S.,Hyogo Prefectural Institute of Public Health and Consumer science | Yoshida M.,Hyogo Prefectural Institute of Public Health and Consumer science
Journal of Mass Spectrometry | Year: 2016

This study described a fragmentation pattern of 21 synthetic cannabinoids with an isopropyl group or a tert-butyl group by electron impact ionization quadrupole mass spectrometry and electrospray ionization time-of-flight mass spectrometry in the positive mode. The compounds were categorized into four types according to substituted group such as a terminal amide and ester. The characteristic fragment ion in each group was obtained. The main common fragment ions for the two ionizations were formed by C-N cleavage of the amide group adjacent to the N-hetero rings. Additionally, the fragment ions indicated the difference in the basic structure as well as substituted group, which are useful for estimating the chemical structures of unknown compounds. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd. Source


Akamatsu S.,Hyogo Prefectural Institute of Public Health and Consumer science | Mitsuhashi T.,Hyogo Prefectural Institute of Public Health and Consumer science
Drug Testing and Analysis | Year: 2014

A simple capillary electrophoresis tandem mass spectrometry method was developed for the simultaneous determination of 20 pharmaceutical components such as cathartics and appetite suppressants in dietary supplements for weight loss. This method allowed multidrug target screening and confirmation in differing radically in chemical structure. The separation was achieved on an uncoated fused-silica capillary using 20 mM ammonium formate in 20 % v/v acetonitrile-water (pH 8.0) as the electrolyte, followed by detection mixed with a sheath liquid that consisted of a mixture of 5 mM ammonium formate and 0.1 % v/v formic acid in 50 % v/v methanol-water. Samples were hydrodynamically injected and separated at 30 kV within 25 min. The limits of detection were 1.0-750 μg/g for the target analytes. The method was successfully applied to 12 dietary supplements for weight loss and 3 non-prescription drugs. The proposed method was suitable as the determination and identification of pharmaceutical components in dietary supplements for weight loss. © 2013 John Wiley & Sons, Ltd. Source


Yoshioka N.,Hyogo Prefectural Institute of Public Health and Consumer science | Asano M.,Kobe University | Kuse A.,Kobe University | Mitsuhashi T.,Hyogo Prefectural Institute of Public Health and Consumer science | And 2 more authors.
Journal of Chromatography A | Year: 2011

We developed a simple and rapid method for the simultaneous determination of phosphorus-containing amino acid herbicides (glyphosate, glufosinate, bialaphos) and their major metabolites, aminomethylphosphonic acid (AMPA) and 3-methylphosphinicopropionic acid (MPPA), in human serum. Serum samples were filtrated through an ultrafiltration membrane to remove proteins. The filtrate was then washed with chloroform, and injected into a liquid chromatography-tandem mass spectrometry (LC-MS/MS) system. Chromatographic separation was achieved on a hydrophilic interaction chromatography (HILIC) column. Determination of the target herbicides and metabolites was successfully carried out without derivatization or solid phase extraction (SPE) cartridge clean-up. The recoveries of these compounds, added to human serum at 0.2. μg/mL, ranged from 94% to 108%, and the relative standard deviations (RSDs) were within 5.9%. The limits of detection (LODs) were 0.01. μg/mL for MPPA, 0.02. μg/mL for AMPA, 0.03. μg/mL for both glyphosate and glufosinate, and 0.07. μg/mL for bialaphos, respectively. © 2011 Elsevier B.V. Source

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