[Development of new analytical technologies and their applications for forensic medical examinations].

Abstract

Quantitation of drug concentration in a cell: Laser-induced photo-thermal microscopy and laser microscope (LSM) were used for quantitation of drug concentration in a cell of the fixed tissue sections. The colloidal gold labeled with antibodies was used as an indicator for detection of drugs or other antigens. The detection limit (10 zmol) of the tobramycin distributed in a epithelial cell of one renal tubule was 10-times superior to that of scanning laser microscope. The colloidal gold remained stable to laser-beam radiation and gave a low background. Therefore, the use of colloidal gold and laser microscopy make possible highly sensitive detection of drug in the fixed tissues. Highly sensitive quantitation of drug: A simple and highly sensitive time-resolved fluoroimmumoassay using a fluorescent europium chelate (4, 4'-bis (1", 1", 1", 2", 2", 3", 3"-heptafluoro-4", 6"-hexanedion-6"-yl)-chlorosulfo-o-terphenyl (BHHCT)-Eu+3) was used for analysis of methamphetamine (MA). Two kinds of assay methods (one step assay and two step assay) using a microtiter plate coated with anti-MA were employed. The smallest measurable amounts of MA for the one-step and the two-step methods were 25 pg/assay and 25 fg/assay, respectively. Molecular biological approach to the forensic problem: a. The diagnosis of the death caused by drowning was possible by detection of the DNA fragments of aquatic plants from the organ of victims. The detection of the DNA fragments of chloroplast gene, ribose-bisphosphate carboxylase large subunit (rbcL), was performed using PCR method with the newly synthesized probes. b. Taq-Man probes were useful to perform the personal identification of many samples. Mitochondrial DNA analysis was also brought about good results for putrefactive samples. So, the combination of some examine methods was need for personal identification of multiple samples. DGGE method was also very useful and easy for multiple gene analysis for personal identification with SNPs.