Identification of body fluids from forensic biological samples is an essential procedure in a criminal investigation. In this study, a systematic method using ELISA for the detection of statherin (STATH), dermcidin (DCD) and Tamm-Horsfall protein (THP) has been developed to identify saliva, sweat and urine, respectively. In addition, it was examined whether this method is suitable for use on body fluid stains, aged stains, and simulated casework samples. Furthermore, the sensitivities of ELISA for STATH, DCD and THP were compared with those of presumptive tests for saliva, sweat and urine, respectively. As a result, saliva, sweat and urine were successfully identified by using the systematic method of ELISA developed in this study. STATH was successfully detected in 2.5-year-old saliva stains and simulated casework samples such as a cigarette butt. Limit of detection (LOD) of STATH by ELISA equated to 31.3 nl of saliva. It would be enough to apply to casework samples although higher than that of blue starch-agarose test. DCD was successfully detected in 7-year-old sweat stains and simulated casework samples such as the surface of a cellular phone. LOD of DCD by ELISA equated to 31.3 nl of sweat, and it was almost similar to that of the Determiner-LA test. THP was successfully detected in 4-year-old urine stains. LOD of THP by ELISA equated to 9.8 nl of urine, and it was almost similar to those of presumptive tests for urea and uric acid. In conclusion, ELISA for the detection of STATH, DCD and THP could be an effective tool for the forensic identification of saliva, sweat and urine because of its specificity and sensitivity. ELISA for the detection of STATH, DCD and THP should be applied to supplement presumptive tests for saliva, sweat and urine.

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  As the first step to develop a liquid chromatography/multiple-stage mass spectrometry (LC/MSⁿ) analytical system which allows us to simultaneously screen relevant drugs and poisons in forensic specimens, an efficient and practical analytical method for correcting LC retention data has been produced utilizing a liquid chromatography/mass spectrometry (LC/MS). The method is based on retention indices (RI). LC/MS employed a C18 (ODS) semi-micro column with a methanol gradient elution program, and the RI values of target substances were calculated on the basis of the retention times of a substance and tri-n-alkylamines, which were chosen as reference markers (internal standards) and respectively assigned RI values. The present study has indicated that RI provides a very reproducible method for correction of retention data. This system has also been found to be a potentially important tool in simultaneously correcting LC retention data of target substances even when we modify the LC conditions such as the solvent-gradient and flow rate. This method will, thus, be successfully incorporated into routine work for forensic investigation.

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  A new method has been developed for the discrimination of white cotton fiber by the detection and comparison of residual surfactants from detergents using liquid chromatography/electrospray ionization mass spectrometry (LC/ESI-MS).
  Twenty three brands of powder-type laundry detergents were collected from 10 manufacturers and used for the study. Standard samples of the surfactants contained in the powdered laundry detergents were offered by the manufacturers of raw materials for detergents. A sample of a washed textile was prepared after washing a T-shirt (cotton 100%) with one of the detergents and drying it. The surfactants in a cotton thread (5 mm in length) taken from the washed T-shirt were extracted into 30 μl of methanol and analyzed by LC/ESI-MS. Analyses of surfactants by LC/ESI-MS was also performed on a detergent itself after the extraction of surfactants into methanol by mixing 400 mg of detergent and 8 ml of methanol followed by centrifuge and subsequent dilution of supernatant 50 times by volume.
  The powder detergents could be classified into 14 groups on the basis of the difference in the combination of 5 surfactants, polyoxyethylene alkyl ether (POE), linear alkylbenzene sulfonate (LAS), α-sulfonato fatty acid methyl ester (α-SF), alkylsulfuric ester (AS), and fatty acid (FAT). Residual surfactants in the washed T-shirt could be detected using 5 mm of thread. The patterns of residual surfactants were found to be similar to those of the detergents except the absence of peaks for some surfactants with relatively short alkyl chains. Mass chromatograms of POE's fragment ion measured at m/z 133 and cone voltage of 50 V in the positive mode allowed the simultaneous detection of POEs with a different length of alkyl chain at a higher sensitivity than those obtained by measuring the molecular ion of each POE at cone voltage of 20 V. Comparison of residual surfactants patterns obtained by the present method was significantly useful for the discrimination of white cotton fiber, which were difficult to differentiate by the morphological characteristics, when the fibers had originated from textiles washed by different detergents.

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  Wheat flour is a common white powder material and sometimes encountered in criminal investigations. This report describes the application of DNA analysis to wheat flour samples for the identification and discrimination of white powder materials. Species identification of commercially available wheat flour samples was carried out by the partial sequence of rbcL, which is used as markers for phylogenetic and taxonomic studies. These wheat flour samples were discriminated by short tandem repeat (STR) analysis and sequence-specific amplification polymorphism (S-SAP) analysis. The partial sequences of rbcL were identical among all flour samples. And they were also identical to the rbcL sequences of wheat (Triticum aestivum L.) submitted to DNA data base. Furthermore, flour samples had characteristic patterns in both the STR and S-SAP analyses. These results suggested that identification of the wheat flour samples was possible by rbcL sequences and both the STR and S-SAP analyses were useful for the discrimination among wheat flour samples. It is considered that DNA analysis of wheat flour can contribute to criminal investigation.

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  In Japan, regular gasoline and premium gasoline are used as fuel for motor vehicles. Sometimes an accident will occur in which regular gasoline was filled by mistake instead of premium gasoline and discrimination between regular and premium gasoline is required in the investigation process. According to the standards, regular and premium gasolines are different only in octane value. Since measuring octane value requires a special device, an alternative method for determining a gasoline sample as a regular or premium one is desired. In this paper a new method for discriminating between regular and premium gasoline utilizing gas chromatography/mass spectrometry (GC/MS) is proposed. Analyzation of regular and premium gasoline collected in December 2007, March, June and September 2008 from gas stations of 15 different brands in northwestern Chiba and eastern Saitama prefecture revealed that, compared to regular gasoline, premium gasoline was rich in alkylate while smaller in 2- and 3-methylhexane concentration. All 120 gasoline samples were correctly classified as either regular or premium gasoline by measuring the ratio of alkylate to methylhexane fractions.

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  Sampling of ignitable liquids such as gasoline and kerosene deposited on arsonist's or robber's hands was studied using headspace-gas chromatography/mass spectrometry. The sampling of the ignitable liquids was carried out by rubbing in four manners of a dry oil sorbent sheet made of nonwoven polypropylene fiber, the oil sorbent sheet wetted with ethanol, dry cotton gauze, and the gauze wetted with ethanol. The analytical results revealed that the sorbents, the oil sorbent sheet and the gauze, wetted with ethanol could extend the term of detection of ignitable liquids deposited on a finger in comparison with the dry sorbents. Kerosene traces were detected up to more than 6 hours after the initial amount of 100 μl was deposited on fingers of three subjects. Gasoline traces were detected up until 30 min at the longest after the initial amount of 100 μl was deposited on their fingers. Sampling method by sorbents wetted with ethanol proposed in this study was suitable for collection of kerosene from hands, while it was unsuitable for that of gasoline. Kerosene deposited on fingers of three subjects was detected by our method even if their fingers were soaped or washed with water. The oil sorbent sheet is suitable for long-term preservation of ignitable liquids such as kerosene because it can control its volatility much longer than the gauze.

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  We investigated the degree of cross-contamination during the punching of FTA cards. Dried or wet FTA cards containing buccal cells were punched with a “Harris Micro Punch”. New FTA micro cards were then punched by the puncher that had either been cleaned by punching clean blotting papers or that had not been cleaned. To detect cross-contamination, DNA was extracted from the new FTA micro cards and was quantified by a Real-Time PCR assay with a detection limit of 0.1 pg/μl. DNA was also amplified using the Identifiler kit to perform short tandem repeat (STR) typing.
  In the Real-Time PCR assay, for the dried FTA cards, DNA was detected in 2 and 3 samples out of 20 samples from the cleaned and the non-cleaned puncher, respectively. For the wet FTA cards, DNA was detected in 3 and 17 samples out of 20 samples from the cleaned and the non-cleaned puncher, respectively. The non-cleaned puncher, after punching the wet FTA card, gave the maximum DNA concentration (0.4 pg/μl). In the STR typing, 2 of 20 samples showed peaks up to approximately 60 RFU (relative fluorescent units) for the non-cleaned puncher after punching wet FTA cards. However, samples produced under the other three conditions showed no peaks above 50 RFU.
  In conclusion, it was thought that the puncher did not need to be cleaned for the STR typing, when FTA cards were dried. In addition, when FTA cards were wet, the cross contamination up to approximately 60 RFU was observed in the STR typing without the cleaning of the puncher, but was reduced by the cleaning.

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