Laboratory Experiences with Oral Fluid Testing Lou Jambor, Ph.D. Rody Predescu, M.D. Quest Diagnostics - Los Angeles Concerns About Drug Detection Times in Oral Fluid Why Oral Fluid Testing? • Ease of Specimen Collection • Collection easily be performed at the Workplace • Clients saves money on collection fees. • Client saves time and problems with urine collection. • Dilution and Adulteration Minimized. Initial Screen • 24 - 48 hours is expected • OraSure Reagents/Intercept Collection Device. • Positive rate very similar to Urine • 96 Well Micro Titer Plates • Tecan Genesis Instrument with Automated Plate Washers and Readers. Tecan Screening Instrument • We are currently running about 1000 specimens/day • Instrument Appears to be very rugged and has had only minimal downtime. • Relatively easy to train staff on instrumentation. Screening Instrumentation • In 8 hours, we can run 632 donor specimens on 2 Systems with 1.5 Technicians. • We would like it to be faster. 1 Screening Cut-Offs (In Buffered Specimen) • • • • • • • Amphetamine Methamphetamine Parent THC Opiates Cocaine PCP Human IgG 100 ng/mL 40 ng/mL 1.0 ng/mL 10 ng/mL 5.0 ng/mL 1.0 ng/mL 0.5 mcg/mL Screening Controls • Controls at 50% and 150% of Cut-Off • Excellent Precision of Controls Screening Cross Reactivity • MDMA: 14 ng/mL on Methamphetamine Assay. Human IgG • Test for Human IgG to verify adequate specimen and human specimen. Screening Cross Reactivity • Excellent Sensitivity for Hydrocodone (13 ng/mL) • Excellent Sensitivity for 6-Acetyl-Morphine (16 ng/mL) Screening Issues • 300 mcL of Specimen • About 700 mcL for Confirmation • MDA: 204 ng/mL on Amphetamine Assay 2 Screening Issues • Overall 81% Confirmation Rate • PCP Confirmation Rate at 40%. Unknown reasons, but appear to be false positives. • Occasional Methamphetamine positive due to Ephedrine. (0.77% Cross Reactivity) Screening Summary • OraSure reagents on Tecan system works very well. • No significant issues. Adventures in GC/MS Confirmations • Quest Diagnostics in Atlanta developed screening and confirmation methods. Instrumentation Summer 2004 • One Varian 1200 Triple Quad for PCP and parent THC. • All other tests on Agilent 5973 • Our task was just to duplicate those methods in Van Nuys. Amphetamines Methamp Methamp 30 30ng/mL ng/mL Agilent Agilent5973 5973 • Amphetamine,Methamphetamine, MDMA and MDA at 40 ng/mL. • Liquid/Liquid Extraction derivatized with PFPA. • Using 200 mcL of specimen, this is a straight forward assay on Agilent 5973 GC/MS. 3 Opiates • Morphine, Codeine, Hydrocodone, Hydromorphone, and 6-Acetyl Morphine at 10 ng/mL with 300 mcL of specimen. • This had to be done on the 5973 and it is clearly a challenge. • UTC extraction columns are the standard method. Opiates • Extraction and GC/MS separations look ugly off the start. • We call Phil Dimson at SPE Ware and the staff at Biochemical Diagnostics to see if they have a better method. • Phil suggests Varian Factor 4 Analytical column. Morphine Morphine10 10 ng/mL ng/mL5973 5973 Opiates • Varian Factor Four Column works great. • Original UTC extraction procedure still the cleanest extract. • 6-Acetyl Morphine is easily detected at 10 ng/mL. Hydrocodone Hydrocodone 10 10ng/mL ng/mL5973 5973 6-MAM 6-MAM 10 10ng/mL ng/mL Agilent Agilent 4 Benzoylecgonine • 2 ng/mL cut-off • Original Procedure called for extraction using SPE Ware Trace B columns. • Agilent 5973 GC/MS with HP-1 analytical column. • We had problems. Benzoylecgonine • We call Phil Dimson at SPE Ware. • He fine tunes things a little. • The real problem was that our Sigma powdered BE-D3 was contaminated with Benzoylecgonine. • Cerilliant Internal Standards are fine. BE BE33ng/mL ng/mL Agilent Agilent5973 5973 Benzoylecgonine • Many other extraction columns were tried, but the SPE Ware column was still the cleanest. • Varian Factor 4 column also very nice for benzoylecgonine analysis in urine. • Resolves a co-eluting peak. PCP and THC • Both analytes at 0.5 ng/mL • We can use the Varian 1200 Triple Quad Varian 1200 PCP and THC • Excellent instrument sensitivity. • We are a factory. We need a standard data handling method. We would like to use Agilent Software. • ProLab conversion between Varian Instrument and Agilent Software is available. 5 ProLab • After much discussion between Varian, ProLab and Agilent we were able to run the Varian with Agilent Software. • This makes life easier. Varian 1200 • Overall an excellent instrument. • Needs to be a little more rugged, but Varian has an excellent applications chemist to trouble shoot instrument and methodologies. Dean Switch • First column isolates the analyte • Narrow time (~ 0.8 min ) around analyte is directed to second column • Resulting in significant improvement in signal to noise. • ~$7,000 Upgrade to 5973. 22ng/mL ng/mLStd Std Dean DeanSwitch Switch No Cryo No Cryo Dean Switch • All analytes can be performed on the Dean Switch. • We routinely run Opiates and PCP on the Dean Switch. • We routinely run THC on the Varian 1200 • Benzoylecgonine and Amphetamines routinely run on conventional 5973 0.5 0.5THC THCStd. Std. Dean DeanSwitch Switch with Cryo with Cryo 6 0.5 0.5THC THCStd Std Varian Varian1200 1200 Positive Rates Confirmed Positive Rate: THC 44% BE: 22% Opiates: 18% Amphetamines: 15% PCP: .05% Positive Rates Oral Fluid Overall: 5.8% THC 44% Opiates 18% Cocaine 22% Amphetamines 15% 5.8% Summary Urine 4.9% 64% 7% 16% 12% Future • I wish the reagent manufactures would develop screening assays for the high through-put instruments. • The Dean Switch holds tremendous potential for all analytical toxicology labs. • Oral Fluid testing will become more prevalent. • The Dean Switch allows low level confirmation with conventional GC/MS instruments in Oral Fluid. Positive Rates Confirmed Positive Rate: THC 44% BE: 22% Opiates: 18% Amphetamines: 15% PCP: .05% 5.8% 7 Positive Rates Oral Fluid Overall: 5.8% THC 44% Opiates 18% Cocaine 22% Amphetamines 15% Summary Urine 4.9% 64% 7% 16% 12% • Oral Fluid testing will become more prevalent. • The Dean Switch allows low level confirmation with conventional GC/MS instruments in Oral Fluid. Future • I wish the reagent manufactures would develop screening assays for the high through-put instruments. • The Dean Switch holds tremendous potential for all analytical toxicology labs. 8
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