Tracing the origin of organic solvents and illicit methamphetamine using GC-IRMS

• Main Authors: Chia-Yi Yang, 楊家懿
• Other Authors: Yong-Chien Ling
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/07823316460604856482

碩士 === 國立清華大學 === 化學系 === 96 === Environmental forensics traditionally used chemical fingerprint to trace the origin of organic solvent pollutants. It fails to identify their origins when the chemical compositions of pollutants are the same. Similarly, drug forensics used impurity analysis to trace the origin of illicit methamphetamine(MA) samples. It also fails to differentiate their origins when MA samples are very pure. Both cases show that it is important to utilize other analytical technique for origin tracing. This study uses compound specific isotope analysis(CSIA) based on gas chromatograph/isotope ratio mass spectrometer(GC/IRMS) to trace the origin of organic solvents and illicit MA samples. The range of the carbon and nitrogen stable isotope ratios(��13C &�n��15N) in organic solvents depend on their origins and manufacturing process, which could be expedited to trace the origin of organic solvents. In this study, the ��13C database of 79 organic solvents was established first. The ��13C of organic solvent components in 33 industrial waste were analyzed later and compared to the database for revealing the correlation between industrial waste and database source. Solvents in industrial waste, such as dichloromethane, toluene, ethyl acetate and isopropyl alcohol, were found to correlate with certain brand solvents in the database. Furthermore, certain industrial waste samples were also found to possess correlations. The distinctions in d-form & dl-form, impurity components, and ��13C &�n��15N of MA depended on the precursor source and synthetic methods. These distinctions could thus be utilized to identify the origin of illicit MA samples and the synthetic route of MA. In this study, 3 synthetic MA samples and 25 seized MA samples were analyzed, including melting point measurement, impurity analysis, and ��13C &�n��15N analysis to identify the correlation between MA samples and their precursor. Furthermore, all MA samples were subjected to statistically analysis for tracing their origin.