Minemasa Hida

Analysis of dimethylamphetamine and its metabolites in human urine by liquid chromatography-electrospray ionization-mass spectrometry with direct sample injection.

An analytical method to identify and determine dimethylamphetamine (DMA) and its metabolites in human urine was developed with liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) involving the direct injection of a urine sample. The urine samples were directly injected by using a gel permeation column, whose stationary phase was polyvinyl alcohol with a small amount of a carboxyl group, so DMA and its metabolites were analyzed rapidly and simply without pretreatment such as extraction, concentration and derivatization. DMA and its metabolites were identified in drug-free human urine spiked with 1 microg of DMA, dimethylamphetamine N-oxide (DMANO) and methamphetamine (MA), and 3 microg of amphetamine (AM) in 1 ml of urine under the full-scan mode. Under the selected ion monitoring (SIM) mode, the limits of detection (signal-to-noise ratio=5) for DMA, DMANO, MA and AM were 20, 20, 20 and 60 ng in 1 ml of urine, respectively. This method was applied to the identification and determination of DMA and its metabolites in urine samples of 10 DMA abusers. The concentrations of DMANO were higher than those of unchanged DMA in all urine samples; thus, DMANO is considered to be a useful metabolite as an indicator to prove DMA intake.

Forensic investigation of counterfeit coins

Counterfeit coins were investigated using X-ray fluorescence (XRF) for a quantitative analysis without any pretreatment and by a metallic microscope for observation of their microstructures. Copper, nickel, iron, zinc, manganese, chromium, cobalt and lead were detected by XRF. Cluster analysis was applied to classify the counterfeit coins using their major six elements (Cu, Ni, Fe, Zn, Mn and Cr). The analytical results showed that the eighty-nine counterfeit coins could be divided into three groups, which were dependent upon the content of iron, chromium and zinc. Many bent micro-structures were observed at the letter and figure position and at the edge using a metal microscope after chemical etching.

Classification of counterfeit coins using multivariate analysis with X-ray diffraction and X-ray fluorescence methods

Counterfeit coins (277 samples) were analyzed by both X-ray diffraction (XRD) and X-ray fluorescence (XRF) methods without any pretreatment. The counterfeit coins were clearly classified into two groups using cluster analysis (CA) and principal component analysis (PCA) for XRD peak patterns. One group (250 samples) was made by a pressed method and another one (27 samples) was made by a nickel-plated method. Using four elements (Cu, Ni, Fe and Zn) and obtaining XRF for 257 samples, they could be divided into four groups by CA. On the other hand, they were classified into five groups using their diameter, thickness, weight, density, density/thickness and density/weight. The latter classification method would suggest something of a change in the process of the pressed method.

Classification of hashish by pyrolysis - gas chromatography

Abstract The classification of hashish was studied by pyrolysis-gas chromatography. To estimate the route through which they had been obtained by suspects, detailed classification of samples of hashish was performed using cluster analysis after normalization of the peaks in the pyrograms against the highest peak in each pyrogram. The results of cluster analysis were presented as a dendrogram, an easily interpreted visual representation of the similarity among samples. The 13 different samples collected were roughly divided into two groups. The observed datum for an unknown sample was evaluated by comparison with the known samples and classified into one of the groups. The dendrogram proved to be effective in discriminating between hashish obtained from different sources.

Determination of the total amount of morphine alkaloids in opium by pyrolysis-gas chromatography using principal component analysis

Abstract The total amount of morphine alkaloids in opium was determined by pyrolysis-gas chromatography (Py-GC) using principal component analysis. The sample suspended in ethanol was added to a pyrolysis foil (590 °C) in the presence of an iron and potassium chloride mixture. The twelve peaks obtained by Py-GC were used for quantitative principal component analysis. The total amount of morphine alkaloids in opium was calculated to substitute the principal component score and factor contribution for the peak area. The total content of morphine alkaloids in opium was found to range from 57.4 to 67.2%.

Capillary-tube isotachophoretic separation of molybdate(VI), tungstate(VI) and vanadate(V) ions using iron-pairing equilibria

Abstract The capillary-tube isotachophoresis technique has been used to separate molybdate(VI), tungstate(VI) and vanadate(V) ions. The ion-pairing equilibria between calcium ion and the above anions can be applied to improve the separation. A simultaneous separation can be achieved when the pH of the leading electrolyte containing calcium ion is 10.0. The separable range of these ions varies according to the concentration of calcium ion, the optimum concentration in the leading electrolyte being 2 m M . The relative standard deviations of simultaneous determinations were 1-0–2.5% at the 3.3 nmol level and the time required for the determination is only 20 min.

Curie-point pyrolysis-gas chromatography of aliphatic amines in the presence of metal powder and inorganic salt

Abstract A fundamental investigation has been undertaken to determine the optimum conditions for the addition of metal powder and metal chloride to a pyrolysis foil for the analysis of aliphatic amines by means of Curie-point pyrolysis-gas chromatography. It is suggested that the effectiveness of the addition of a suitable inorganic salt to the pyrolysis foil is associated with the ability of the metal ion to complex with amines. Nickel powder was useful when the pyrolysis was carried out at lower temperatures and chromium was preferred at higher temperatures. The suitable pyrolysis temperature was related to the molecular weight of the amine samples. The optimum conditions for the pyrolysis of three butylamines resembled one another. The recommended conditions for dibutylamine hydrochloride are that the pyrolysis be carried out at 333°C in the presence of a mixture of nickel powder and cobaltous chloride hexahydrate (10:3 w/w). The calibration curves for dibutylamine hydrochloride, constructed by using the peak area method, were linear over the sample size range of 2.1–41.2 μg. The relative standard deviation (n = 4) was 2.56% for 20.6 μg.

Determination of alkaloidal narcotics by pyrolysis-gas chromatography

Abstract The alkaloidal narcotics in urine are extracted with dichloromethane and heated to evaporate the solvent. The salts of alkaloidal narcotics are pyrolyzed and analyzed by gas chromatography. By this method, the alkaloidal narcotics can be determined with high sensitivity and with good reproducibility.

Classification of prepaid cards based on multivariate treatment of data obtained by X-ray fluorescence analysis.

Two hundred prepaid cards, which had been used in Nagoya-citys subway in Japan, and another 32 prepaid cards (11 were real turnpike cards, 20 were counterfeit cards and 1 was a white card) were evaluated by X-ray fluorescence (XRF) without any pre-treatment. A preliminary investigation was performed on 200 prepaid cards in order to find an identification method for the turnpike cards. By plotting the relative intensity of titanium versus that of iron obtained by XRF, the cards were clearly classified into seven groups. On the other hand, the cards could be divided into four groups by a multivariate analysis using the relative intensities of five elements such as chlorine, calcium or tin, titanium, iron and barium. Using these results to classify the Japanese turnpike cards, they were divided into three groups or two groups. One of three groups or two groups was the counterfeit card group.

Determination of triazolam in a drug tablet by thermal desorption gas chromatography

Abstract Thermal desorption gas chromatography using a vertical microfurnace pyrolyzer was applied to determine the amount of triazolam in a tablet sample. About 1 mg of ground tablet was directly subjected to analysis without any preconcentration. When the sample was heated at 300°C, triazolam desorbed from the powder was observed as a completely isolated peak in a chromatogram together with some additional peaks formed from the main components of the tablet through pyrolysis and/or thermal desorption. The correlation coefficient of the calibration curve obtained by use of pure triazolam ranging from 2.4 to 10.5 μg was 0.999. Triazolam in the tablet sample (about 3 μg/mg) could be determined using the calibration curve. The relative standard deviation of this method was 2.4% for four runs.