SDTL News January 2010 Volume 1 Issue 1 Clients receive custom solu- Phosphatidylethanol test more sensitive than CDT marker tions with USDTL by Douglas Lewis by Heather Sliwinski President and Scientific Director Lund University method vs. USDTL method PEth Sales and Marketing Associate Recent studies have A drug treatment program participant claims indicated that the direct they are sober. The program supervisor suspects alcohol biomarker phos- a relapse. The participant is using an unusual phatidylethanol (PEth) is drug of abuse. After hours of grueling research, superior to indirect mark- the supervisor still cannot find a laboratory that ers like carbohydrate de- tests for the drug, leaving them without options ficient transferrin (CDT). to monitor their participant. PEth is a pathological Clients of USDTL run into the same ob- phospholipid formed in tis- stacles, but experience different outcomes. We sues only by the action of assist our clients by tailoring a monitoring pro- phospholipase D on phos- gram to meet their specific needs, even if the phatidylcholine and etha- solution does not yet exist. nol. PEth in blood remains Recently, a valu- in the red cell membrane able client contacted until it spontaneously hy- USDTL concern- drolyses or is oxidized by ing a sevoflurane lipid peroxidation. abuser in their treat- USDTL took part in Dr. ment program. The Marques’ DUI and biomar- rhosis, among others, are present. Also, im- program suspected kers research by re-analyzing 281 blood proved test methods in PEth appear to have a relapse, while the specimens that had been previously analyzed reduced the other issues related to gender and participant denied it. for PEth at Lund University using a less sen- age. Because of the lack of false positives The program con- sitive HPLC/Light Scattering detector (LC/ along with its high sensitivity for detecting ducted a search for LCD). The LC/LCD has a limit of quantita- alcohol consumption, researchers conclude an organization that tion of 250 ng/mL of total PEth which rep- that it’s the most sensitive and specific alco- offered such a test. resents 100 ng/mL of the specific isomer of hol biomarker available. ©iStockphoto.com/matthewzinder Without any suc- PEth USDTL determines by LC/MS/MS. For these reasons, USDTL now offers SM USDTL can create custom cess, the administra- The USDTL method has a limit of quantita- PEthStat using blood samples to test for tests for unusual drugs of tor contacted US- tion of 20 ng/mL. As seen from the correla- alcohol exposure. The CDT assay requires abuse, like the anesthetic DTL President and tion chart, many specimens negative by LC/ consumption of 60 grams of ethanol per day sevoflurane. Scientific Director LSD were positive by USDTL’s LC/MS/MS for 10 days to 14 days to produce a positive, Douglas Lewis. method. Overall, the methods showed amaz- while PEthStatSM only requires about one “I had never heard of sevoflurane being ing agreement with an r2 of 0.846. drink a day per week. Therefore, pairing abused, so I didn’t know if the gaseous anesthet- Using LC/MS/MS methodology, PEth PethStatSM with UrineStatSM EtG/EtS, offers ic would be entirely metabolized and present in analysis can identify as little as one drink (12 a unique combination of alcohol biomark- a urine sample,” said Lewis. Lewis wanted to grams EtOH) per day over a week’s period. ers for added insurance for your drug test- research the drug further with his new applica- As a direct biomarker, PEth is not subject to ing program. Requested sample volume is 5 tions department to see if assay development the numerous pathological conditions that milliliters of blood, and results are available would even be possible. can produce false positives for CDT. A CDT four days to seven days after the sample is Lewis and his team are no strangers to devel- test can produce false-positive results for al- received in the laboratory. Call 1-800-235- oping new methods after a client inquiry. Vice cohol use when pathological conditions such 2367 to order PEthStatSM collection materials President Joe Jones remembers developing an as obstructive liver disease and liver cir- or visit www.usdtl.com for more information. array of methods simultaneously for one client. “At the specific request of a client, we devel- FID methodology, handing the reins to the GC- New ketamine test now available oped, validated and launched 10 assays in about FID expert, Chetan Soni, who validated the as- six months,” said Jones. “The standards were by Joseph Jones say in urine samples within the week. hard to find, and after an extensive search to Vice President Laboratory Operations “The client was very pleased with our timely obtain them, we still had to custom synthesize results,” said Jones. “Their program now has a USDTL now offers testing for ketamine and the internal standards.” But Jones kept working new tool at its disposal to assist with the recov- its metabolite norketamine in urine, hair and when other laboratories would stop, successful- ery of this program participant.” nail samples. The ketamine test is an add-on ly launching the 10 new tests. In this case, the Within one week of the initial discussion, assay to any urine, hair or nails profile and may sevoflurane test would not be as tricky. USDTL researched, developed, validated and also be ordered separately. The ketamine assay “After reviewing the literature, I found that launched an assay specific to a client’s needs. uses liquid chromatography-tandem mass spec- sevoflurane is metabolized after use,” said “We are a laboratory business run by labo- trometry testing, with cutoffs of 100 ng/mL for Lewis, “and the metabolite is a common chemi- ratory people, not businessmen,” said Lewis. urine and 100 pg/mg for hair/nails. cal found in a commercial laboratory.” “We have the capacity to get things done. If Ketamine is marketed as a general anesthetic Once Lewis found the metabolite, hexafluor- ® you run into a problem, just ask. We’ll do our for human and veterinary use (Ketanest , Keta- oisopropanol, he, Jones and Laboratory Director ® ® best to see if we can solve it.” set and Ketalar ). Because of its dissociative Chuck Plate, who has a doctorate in biochem- Discuss your specific needs with one of our properties, ketamine is diverted for recreational istry, discussed the methods. Further research staff toxicologists at 1-800-235-2367. use and date rape, and has become a popular indicated that detection was possible using GC- contributions by Joe Jones, vice president club drug. Ketamine is available as a clear liq- uid and a powder that may by injected, smoked References -DUI risk prediction with alcohol biomarkers, interlock or consumed in drinks. -http://www.justice.gov/dea/concern/k.html. records, and self-report, in Proceedings of the T2007 Joint International Meeting of TIAFT/ICADTS/IIS, According to the National Institute on Drug -http://www.drugabuse.gov/Infofacts/clubdrugs.html. Abuse in 2007, 1 percent of eighth-graders, -Y. Hijaze, M. Bolon, and R. Boulieu. Stability of August 26-30 (2007). Author(s): Marques, P.; Javors, M.; Ketamine and Its Metabolites Norketamine and Wurst, F.; Pragst, F.; Yegles, M.; Alling, C.; Auwaerter, 0.8 percent of tenth-graders and 1.3 percent of Dehydronorketamine in Human Biological Samples. V.; and Aradottir, S. twelfth-graders reported use of ketamine in the Clinical Chemistry 47/9 (2001) p. 1713-1715. past year. Reports indicate an increase in keta- 1700 S. Mount Prospect Rd. | Des Plaines, IL 60018 | (800) 235-2367 | www.usdtl.com mine abuse and fatal poisonings. © 2010 United States Drug Testing Laboratories .