Nariaki Takayama

Simultaneous determination of cyanide and thiocyanate in blood by ion chromatography with fluorescence and ultraviolet detection

An ion chromatographic method for the simultaneous determination of cyanide and thiocyanate in blood has been developed. After extraction by adding water and methanol to blood, cyanide was derivatized with 2,3-naphthalenedialdehyde and taurine to give a fluorescent product of 1-cyanobenz[f]isoindole. This compound was detected with high sensitivity by fluorometry and the underivatized thiocyanate was detected by ultraviolet absorption. The detection limits were 3.8 pmol ml(-1) for cyanide and 86 pmol ml(-1) for thiocyanate, and the recoveries from blood were ca. 83% and ca. 100%, respectively. The proposed method was successfully applied to the analysis of both anions in blood from smokers, non-smokers and fire victims.

Simultaneous chiral determination of methamphetamine and its metabolites in urine by capillary electrophoresis-mass spectrometry

A capillary electrophoresis-mass spectrometry method for the simultaneous chiral determination of enantiomers of methamphetamine (MA), amphetamine (AP), dimethylamphetamine (DMA) and p-hydroxymethamphetamine (pOHMA), in urine has been developed. The internal standards used were 2-phenylethylamine and 1-amino4-phenylbutane. The electrolyte was 1 M formic acid (pH 2.2). The chiral selector, which was added to the electrolyte, was a mixture of 3 mM beta-cyclodextrin and 10 mM heptakis(2,6-di-O-methyl)-beta-cyclodextrin. The detection limits were 0.03 microg ml(-1) for the enantiomers of MA and AP and 0.05 microg ml(-1) for the enantiomers of pOHMA using selected ion monitoring. In the analysis of healthy adult urine samples spiked with MA, AP and pOHMA, the precision of within-run assays (n = 4) for the migration time after correction with two internal standards were under 0.04%, and the detection yields utilizing solid phase extraction were 95-105%. This method was applicable to the analysis of urine samples of MA addicts and DMA addicts.

Simultaneous chiral analysis of methamphetamine and related compounds by capillary electrophoresis

A capillary electrophoretic method for the simultaneous chiral analysis of nine cationic drugs (18 enantiomers) has been developed. These drugs are methamphetamine (MA), amphetamine, dimethylamphetamine, ephedrine (EP), norephedrine, methylephedrine, 3,4-methylenedioxymethamphetamine, 3,4-methylenedioxyamphetamine and 3,4-methylenedioxy-N-ethylamphetamine. The chiral selector, which was added to the electrolyte, was a mixture of beta-cyclodextrin and heptakis(2,6-di-O-methyl)-beta-cyclodextrin. The detection limits of all enantiomers were 0.1 microg/ml, and the intermediate precisions of migration time and peak area of within-run assays (n=6) were under 0.3% and 1.4%, respectively. The calibration curves of the peak area of (1R,2S)-(-)-EP and S-(+)-MA were linear in the range 0.2-500 microg/ml. This method was applicable to urine analysis.

Determination of methamphetamine, amphetamine and piperidine in human urine by high-performance liquid chromatography with chemiluminescence detection.

A high-performance liquid chromatographic method for the determination of trace levels of methamphetamine, amphetamine and piperidine in human urine is reported. The three compounds, extracted into diethyl ether from alkaline urine, were derivatized with dansyl chloride, then separated on a reversed-phase column and detected by chemiluminescence after reaction with bis(2,4,6-trichlorophenyl) oxalate and hydrogen peroxide. The corresponding peaks obtained from human urine were identified as the dansyl derivatives by mass spectrometry. Methamphetamine levels as low as 2 x 10(-10) M in urine were determined. The sensitivity of the method is higher than that of Simons reagent test and gas chromatography.

Determination of stimulants in a single human hair sample by high-performance liquid chromatographic method with chemiluminescence detection.

Stimulants that are controlled by the Stimulant Drug Control Law of Japan are methamphetamine (MA) and amphetamine (AP). MA is used by most stimulant addicts, and AP is detected as its main metabolite. We have developed a high-performance liquid chromatography method with chemiluminescence detection (CL-HPLC), for determining trace levels of MA and its metabolites in a single human hair sample, in which bis(2,4,6-trichlorophenyl)oxalate and hydrogen peroxide are the postcolumn reagents. After washing a single hair sample with water and methanol, it was cut into pieces, extracted with a mixed solution of methanol and hydrochloric acid for 1 h under ultra-sonication and allowed to stand at room temperature overnight. Then the organic phase was evaporated to dryness. To the residues, 0.1 mL of carbonate buffer and 0.1 mL of dansyl chloride solution were added and the solution was heated at 45 degrees C for 1 h. An aliquot of the reaction mixture was then subjected to HPLC. MA and AP were chemiluminogenically detected as their dansyl derivatives from a sample of only a single hair. The detection limit was about 2 pg in an injected volume (20 microliters), and about 20 pg in a single hair sample. This detection limit was smaller than that by the gas chromatography/mass spectrometry (selective ion monitoring) method. Our method was useful as a screening test for stimulant users.

HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY STUDY ON EFFECTS OF PERMANENT WAVE,DYE AND DECOLORANT TREATMENTS ON METHAMPHETAMINE AND AMPHETAMINE IN HAIR

Black hairs that had been removed from a methamphetamine (MA) addict were treated with permanent wave, dye or decolorant liquids, and MA and amphetamine (AP) were quantified by a high-performance liquid chromatography/chemiluminescence detection method. The concentrations of MA and AP in the hair decreased significantly in all cases. Both MA and AP were stable in the permanent wave treatments, but not stable in the dye or decolorant treatments. As possible reasons for the decrease, the elution of MA and AP from hair in the permanent wave treatment, and the degradation of MA and AP in the dye or decolorant treatments might be considered. These results suggested that treatments of hair with permanent wave, dye or decolorant liquids interfered with determination of MA and AP in hair.

Reproducible chiral capillary electrophoresis of methamphetamine and its related compounds using a chemically modified capillary having diol groups

Excellent reproducibility of chiral capillary electrophoresis for methamphetamine (MA) and its related compounds was obtained using a chemically modified capillary having diol groups. The data were compared with those using an untreated fused-silica capillary and a poly(vinyl alcohol) (PVA)-coated capillary. For five replicate analyses of a standard mixture, relative standard deviations (RSDs) of the migration times of analytes with diol or PVA-coated capillaries were less than 0.1%, which were lower than those obtained with an untreated fused-silica capillary (ca. 0.4%). The diol capillary gave reproducible migration times especially in analyses of real samples, such as crude human urine. In the analyses of five spiked urine samples, the RSD values of migration times of analytes with the diol capillary were not greater than 0.14%, which were much lower than those obtained with the PVA-coated capillary (ca. 1.5%). The proposed method was successfully used for chiral analyses of actual urine samples of MA addicts.

Differentiation of AB-FUBINACA positional isomers by the abundance of product ions using electron ionization-triple quadrupole mass spectrometry.

Mass spectrometric differentiation of structural isomers is important for the analysis of forensic samples. Presently, there is no mass spectrometric method for differentiating halogen positional isomers of cannabimimetic compounds. We describe here a novel and practical method for differentiating one of these compounds, N-(1-amino-3-methyl-1-oxobutan-2-yl)-1-(4-fluorobenzyl)-1H-indazole-3-carboxamide (AB-FUBINACA (para)), and its fluoro positional (ortho and meta) isomers in the phenyl ring by electron ionization-triple quadrupole mass spectrometry. It was found that the three isomers differed in the relative abundance of the ion at m/z 109 and 253 in the product ion spectra, while the detected product ions were identical. The logarithmic values of the abundance ratio of the ions at m/z 109 to 253 (ln(A109 /A253 )) were in the order meta < ortho < para and increased linearly with collision energy. The differences in abundances were attributed to differences in the dissociation reactivity between the indazole moiety and the fluorobenzyl group because of the halogen-positional effect on the phenyl ring. Our methodology, which is based on the abundance of the product ions in mass spectra, should be applicable to determination of the structures of other newly encountered designer drugs. Copyright

Analysis of 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid and its glucuronide in urine by capillary electrophoresis/mass spectrometry

Δ(9) -Tetrahydrocannabinol is the primary psychoactive component in cannabis, one of the most commonly used illicit drugs in the world. This paper describes a simple and rapid method for direct analysis of major metabolites of Δ(9) -tetrahydrocannabinol; 11-nor-Δ(9) -tetrahydrocannabinol-9-carboxylic acid and its glucuronide in urine by capillary electrophoresis/mass spectrometry. The only pretreatment needed for a urine sample was dilution with methanol containing an internal standard and centrifugation. Electrophoresis was carried out in an untreated fused-silica capillary (50 µm i.d. × 85 cm) filled with 40 m m ammonium formate (pH 6.4). An analysis could be completed within 10 min. For both compounds, the assay was linear over the range 0.1-10 µg/mL in urine with correlation coefficients (r(2) ) >0.99 and the limit of detection was 0.5 pg (10 nL injection). The detection yields and reproducibilities were determined at three different concentrations (0.1, 0.5 and 2 µg/mL in urine). The mean detection yields were 60-99%. The intra- and inter-day relative standard deviations of migration times were 0.063-0.19 and 0.18-0.36%, and those of peak areas were 4.2-18 and 5.9-25%, respectively. The proposed method successfully analyzed the urine samples of cannabis users.

Fatal and non-fatal cases of lime sulfide exposure and pathogenetic mechanisms underlying pancreatic injury: Case reports with an animal experiment

Lime sulfide poisoning by the oral route is rarely encountered in the practice of forensic science, whereas hydrogen sulfide poisoning is seen frequently. We report here two cases of fatal lime sulfide poisoning with several related cases and in addition induced histological damage with acute inflammation in animal models under at similar concentrations. We also evaluated sulfide and thiosulfate concentrations and speculated as to the cause of pancreatic damage in these cases.