The Royal Canadian Mounted Police (RCMP) Forensic Laboratory Services (FLS) needed a method to confirm positive lysergic acid diethylamide (LSD) immunoassay screening results. As a result, an ultra performance liquid chromatography tandem mass spectrometry (UPLC¢â/MS/MS) method was validated for the confirmation and quantitation of LSD, iso-LSD, N-demethyl-LSD (nor-LSD), and 2-oxo-3-hydroxy-LSD (O-H-LSD). The method was validated in urine and whole blood, where linearity, accuracy, precision, sensitivity, stability, selectivity, recovery, matrix effects, and reproducibility were evaluated. <p>The method involved a liquid-liquid extraction (LLE) of the analytes and the deuterated internal standard from 1 mL of urine or whole blood with dichloromethane:isopropyl alcohol after being basified. The average recovery for all analytes was ¡Ã 62%, and the matrix effect was found to be insignificant. MS/MS analysis was conducted with a triple quadrupole mass spectrometer by positive electrospray ionization (ESI+) in multiple reaction monitoring (MRM) mode. The lowest limit of quantitation (LLOQ) was 20 pg/mL for LSD and iso-LSD, and 50 pg/mL for nor-LSD and O-H-LSD. The method was linear, accurate, precise, selective, and reproducible from 20 to 2000 pg/mL for LSD and iso-LSD, and from 50 to 2000 pg/mL for nor-LSD and O-H-LSD with an r2 ¡Ã 0.99. <p>The refrigerated and frozen long term stability was investigated for 90 days. LSD was stable at all temperatures for 90 days. Iso-LSD in blood was also stable at all temperatures for 90 days, but iso-LSD in urine showed an initial decrease followed by a gradual increase back to day 0 concentrations. Nor-LSD was stable at all temperatures up to day 14, with >43% decrease by day 30, with no additional decrease for the next 60 days. O-H-LSD in urine was stable at all temperatures for 90 days, but by day 90 O-H-LSD in whole blood stored refrigerated decreased in concentration by >37%. Additionally, a case sample that was stored at -50¡ÆC for ten years was found to still contain measurable amounts of each compound. <p>The method was applied to blind samples and a case that screened positive with immunoassay. Retention time, relative retention time, and ion ratios were used as identification parameters and found to correctly identify the analytes 100% of the time with no false positives. The case sample showed that the concentration of O-H-LSD was 4 times greater than LSD in urine. Furthermore, both the detection of O-H-LSD in a blood case sample, and LSD in a vitreous humor case sample were the first to be documented.
| Identifer | oai:union.ndltd.org:USASK/oai:usask.ca:etd-04202006-102806 |
| Date | 20 April 2006 |
| Creators | Chung, Angela |
| Contributors | McKay, Gordon, Hudson, Jeff J., Blakley, Barry R., Ross, Andrew R. S. |
| Publisher | University of Saskatchewan |
| Source Sets | University of Saskatchewan Library |
| Language | English |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://library.usask.ca/theses/available/etd-04202006-102806/ |
| Rights | unrestricted, I hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to University of Saskatchewan or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report. |
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