Screening method for determining plant proteinous toxin ricin was developed using polyacrylamide gel electrophoresis (PAGE) and matrix-assisted laser desorption ionization-time of flight-mass spectrometry (MALDI-TOF-MS), which are based on the estimation of molecular weight of proteins. From authentic ricin, two protein bands with about 60 kDa were observed by non-reduced sodium dodecyl sulfate (SDS)-PAGE and microchip electrophoretic protein analysis using Agilent 2100 BioAnalyzer. From reduced authentic ricin, several protein bands with about 30 kDa, which are derived from ricin A-chain (RTA) and B-chain (RTB), were observed. Two distinct peaks, which are derived from singly (m/z 62,592) and doubly (m/z 31,401) protonated molecular ions, were detected on the mass spectrum of authentic ricin by MALDI-TOF-MS. Two partly-overlapped peaks around m/z 31,000-32,000, which are derived from singly protonated molecular ions of RTA and RTB, were observed for reduced authentic ricin. It was concluded that the developed analytical methods based on the estimation of molecular weights with and without reduction are useful for screening of ricin.

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In case of oil spill on the ocean, identification of the origin of spilled oil is very important for further investigation. However, it is difficult to distinguish between gas oils and fuel oil “A”s by using FID-gas chromatography because of apparent similarity in the chromatographic patterns obtained from these oils, especially when the oils are weathered.
In this report, we developed a new method to distinguish unknown oils into gas oils and fuel oil “A”s, using gas chromatographic/mass spectrometry with selected ion monitoring (GC/MS/SIM). Dibenzothiophene (DBT) derivatives (e.g., 4-methylDBT, 4,6-dimethylDBT, etc.) were found to be used as index compounds for classification of oils. DBT derivatives were detected clearly from the fuel oil “A”s by GC/MS/SIM monitored at m/z 198 and 212 but not from gas oils. It should be noted that chromatographic patterns of DBTs were unchanged even if these oils were highly weathered. These results indicate that the present method is useful for identification of spilled oils on the ocean.
Moreover, further classification of chromatographic patterns from fuel oil “A”s and comparison of index peak ratios (4MDBT/C16) were found to be useful to distinguish among fuel oil “A”s from different origins even if these oils were weathered to some extent.
Although it is often that only very small amounts of oil samples could be obtained from the ocean, the high sensitivity of GC/MS/SIM enabled to analyze them.

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Application of refractive index (RI) measurement and analysis of trace impurities with synchrotron radiation X-ray fluorescence spectrometry (SR-XRF) was investigated for the forensic discrimination of headlight glasses. Glass fragments smaller than 1 mm were collected from 17 kinds of different headlight samples for this experiment. It was found that glass fragments taken from the surface of the headlight was not appropriate for the forensic comparison and should be excluded from the RI measurement, because some of them showed inappropriate RI values different from those of the fragments from the bulk. Discrimination of headlights was carried out by comparing the range of average RI value ±2SD among 136 possible pairs of the 17 samples. The comparison of RI could distinguish 118 pairs and but not the other 18 pairs. As a result of SR-XRF analysis for the 17 sample headlights, 8 elements (Zn, As, Sr, Zr, Sb, Ba, Ce and Hf) were selected for the comparison, because these elements were considered to be effective for the discrimination. The X-ray intensities of these elements were normalized using the element which provided the highest X-ray intensity in each X-ray measurement and was followed by cluster analysis. In the dendrogram obtained, 11 of 17 pairs of data measured with 2 fragments taken from the same sample on different experimental days were classified into the nearest cluster. This result indicates that the analysis of 8 elements by SR-XRF could give useful information for the discrimination of headlight glasses. The number of indistinguishable pairs was reduced to 4 from 18 by the addition of analytical results using SR-XRF to the results of RI measurement, which demonstrates that the combination of these two methods could achieve significant improvement in the discrimination capability of headlight glasses.

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Discrimination between fuel oils A (No. 1 and No. 2 with less than 5000 and 20000 ppm of sulfur contents, respectively) and diesel fuel with less than 50 ppm of the sulfur content was studied using a gas chromatograph-mass spectrometer (GC-MS). Mass chromatograms (MC) of m/z 184, 198, and 212 for dibenzothiophene (DBT), methyldibenzothiophenes (C1-DBT), and dimethyldibenzothiophenes and ethyldibenzo thiophenes (C2-DBT), respectively, corresponded to the chromatograms of the compounds in the oils by gas chromatography-atomic emission detection. These compounds are main sulfur compounds in the oils. The MC analysis of DBT, C1-DBT, and C2-DBT could rapidly discriminate between the diesel fuel and the fuel oils A. In the case of analysis of contaminated oil samples, the oils were cleaned-up and fractionated into two fractions on a florisil column prior to the GC-MS analysis. The first and second fractions were eluted with hexane and hexane-chloroform (2 : 1), respectively. The second fraction contained sulfur compounds together with aromatic hydrocarbons. The MC analysis of the sulfur compounds in the second fraction also discriminated the three types of oils. This method has the advantage of requiring only a sub-microliter of sample amount and a scan mode of GC-MS measurement for the discrimination of the three types of oils.

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This paper reports a comparison study of headspace sampling with microextraction devices for detecting an accelerant such as motor gasoline from fire debris collected at the fire scene. Microextraction devices compared solid-phase microextraction (SPME) device and improved gastight syringe. This microextraction device is made from 250 μL volume gastight syringe and 6-cm length GC column. The inside of this short GC column is mounted with an activated charcoal powder. Extraction procedure is performed by the strokes of the plunger in this microextraction gastight syringe (MEGS). The extraction of volatile organic compounds with MEGS is the same as the principle of the dynamic headspace concentration with an absorption tube. Compared to SPME, MEGS is a practical device for headspace sampling of volatile organic compounds with high concentration capability.

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This study has revealed the advantages of synchrotron radiation high-energy X-ray fluorescence spectrometry (SR-XRF) utilizing 75.5 keV X-rays at SPring-8 BL37XU for trace elemental analysis of forensic samples. The lower limits of detection (LLD) values calculated from calibration curves were pg levels for Ba, Ce, and Sm and 10 pg levels for Sr, Zr, Sn, and Hf. K-line peaks of 31 elements, including rare-earth elements, could be detected in the spectrum of NIST SRM 612 glass and the relative standard deviations (RSD) of all the measured elements except Ca were less than 9.7%. Fragments from collected 6 sheet glasses were used in order to examine the capability of this technique of forensic discrimination of glass fragments. Several trace elements such as Pb, Rb, Sr, Zr, Mo, Ba, La, Ce, and Hf were detected in these samples and could be used as important indexes to characterize the glass samples. This technique can provide an effective approach to the nondestructive discrimination of small glass fragments.

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A mixed solution of 28% of ammonia and pyridine (9 : 1 (v/v)) was used to extract dye ink from counterfeit paper money printed by an ink-jet printer. The counterfeit paper money was fixed on a vacuum filtration device instead of a membrane filter. The extracted solution was collected in a test tube and was evaporated to dryness under reduced pressure in a 40°C water bath. The extract was dissolved by 10 μl of the extraction solution and spotted on a silica gel plate. The silica gel plate was developed by iso-propanol : 28% ammonia : pyridine (2 : 9 : 1 v/v/v). By comparison with TLC patterns, we could clearly distinguish among the various printer companies. Furthermore the TLC pattern was discriminated between the machine types to some extent.

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In the case of food poisoning by injection for foods packaged in polypropylene bags, the shape of the hole on the bag is compared with that of the controlled holes to detect the type of needle that was used.
A method was developed to make controlled holes by needles at various angles on polypropylene bags and many images of controlled holes were obtained.
Almost all controlled holes were accompanied by scratch marks. There were some correlation between injection needle diameters and scratch widths.
The images of controlled holes are useful for checking rupture lines of suspected sample film and estimating the angle of the injection needle. Also the images are useful to make control samples efficiently. The reported method is simple so that one can make a variety of controlled holes depending on the suspected needles or suspected films.

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Nondestructive identification of synthetic quartz crystal seals was carried out by Raman and infrared spectroscopies. The micro laser Raman spectroscopy was very useful for identification of quartz crystal because the Raman peaks of quartz were obtained in the range from 100 to 1200 cm^-1. The discrimination between natural and synthetic clear quartz crystals was achieved using the Fourier transform infrared spectroscopy because the hydroxyl stretching vibration bands at 3595 cm^-1 and 3585 cm^-1 were characteristic of synthetic and natural ones, respectively.

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If the suspect left his/her fingerprints at a crime scene, depending on the types of crimes, i.e. whether it was a crime by the resident of the scene, crime by the person who had been in the scene, or crime by the person who discovered the crime, etc., the time when they were impressed often becomes a point of issue in the trial. Although some data on the change in the quality of fingerprints with the passing of time were already reported, they were based only on those over a short period of time. The change of the quality of fingerprints varies by individual differences, conditions when they were impressed, types of objects on which fingerprints were impressed, and conditions of places where fingerprints were kept. In this report, we made an experiment on the change of quality of fingerprints over a period of 10 years. The data of aging impressed fingerprints will contribute to scientific investigation.

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5-Methoxy-N,N-diisopropyltryptamine (5-MeO-DIPT) has hallucinogenic activity and has been prohibited by the Narcotics and Psychotropics Control Law in Japan since April 2005. In general, to prove of drug ingestion, the urine is the most popular and effective sample for the analysis, because it is easy to collect and the parent drug and its metabolites are relatively concentrated in it. Therefore, it is very important to identify the metabolites in urine. But with respect to 5-MeO-DIPT, the investigation about its metabolites has not been performed sufficiently.
In this paper, with the aim of detecting basic metabolites, 5-MeO-DIPT and related compounds were extracted from the abuser's urine which had been stored at -20°C for about 2 years, with liquid-liquid extraction under alkaline condition and solid-phase extraction using two types of cartridges (reversed-phase, Oasis^® HLB and mixed-mode, Oasis^® MCX), and analyzed by gas chromatography/mass spectrometry (GC/MS). Although slight decomposition may have occurred during storage, 5 related compounds were detected and the structures of these compounds were presumably identified.
5-Hydroxy-N,N-diisopropyltryptamine and 5-methoxy-N-isopropyltryptamine were detected as the main metabolites with the parent drug, 5-MeO-DIPT. The concentration of 5-MeO-DIPT was measured to be 1.1 μg/ml when the drug was extracted with Oasis^® MCX. In addition, the trace amounts of 2 related compounds which were thought to be 5-hydroxy-N-isopropyltryptamine and 6-hydroxy-5-methoxy-N,N-diisopropyltryptamine-N'-oxide were detected. Furthermore, one metabolite which was assumed to be 5-methoxy-N,N-diisopropyltryptamine-N'-oxide in the reference paper was suggested to be 6-hydroxy-5-methoxy-N,N-diisopropyltryptamine, judging from the results of the extraction behavior.

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