Niedbala R.S.. Burton J., Fasolka S., Feindt H.H., Jinks C , Kuntz C , Parmar G., Waga J., Salamone S.J.
OraSure Technologies, Bethlehem, PA, USA
The UPlink™ system is a new on-site technology platform that has been developed for the rapid detection of drugs of abuse in oral fluid. The UPlink system uses AN imrnunochromatographic method that employs Up-Converting Phosphor Technology (UPT) as the reporter. UPT is based on nanometer inorganic phos-phor particles that up-convert infrared light to visible light. The exquisite sensitivity and low background of the UPlink label provide for a highly reproducible immunoassay with little interference. The data pre-sented focuses on the performance of UPlink to specifically determine the semiquantitative concentration of a series of opiates in oral fluid. Non-clinically, the assay was tested for a number of parameters inclu-ding precision, sensitivity, cross-reactivity, and effects of interférants. Clinically, the assay was tested in five locations using multiple operators in order to demonstrate accuracy as compared to Intercept™ oral fluid drug test and GC-MS-MS. In non-clinical studies, the precision of the test was determined by testing twenty replicate specimens at three sites using concentrations of ±25 and ±50 % of the target cutoff concentration of 40 ng/mL. The results of the precision are listed in the following table :
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Windows of detection for opiates using oral fluids
Niedbala R.S.. Salamone S.J., Hunter R, Clarke J., Feeley B.OraSure Technologies, Inc. 150 Webster Street Bethlehem, PA , USA
As the growth of oral fluids testing for drugs of abuse continues, questions on the windows of detection for substances of interest remain. In this study oral fluids were collected using the Intercept Oral Fluids Collection Device from over 500 individuals who self-reported abusing heroin within the last 12 hours.
Following collection, the samples were tested using the corresponding microtiter plate EIA designed for use with the Intercept collector. The EIA used is specific for a broad range of opiates. The kit is calibra-ted against morphine and is 65 % and 43 % cross-reactive to 6-acetylmorphine and diacetylmorphine, res-pectively. Across the population studied, the window of detection for opiates was as long as 144 hours with the majority of individuals detectable between 0.5 and 60 hours by EIA. The results of this study are consistent with other reports on the clinical sensitivity of opiates in oral fluid. Previous studies have shown the time to peak level of opiates in oral fluid and blood to be two hours whereas the peak level in urine was 12 hours. Additionally, opiates were detected in oral fluids and blood in as short as 30 minutes while appreciable levels of opiates in urine were not detected for the first four hours. Thus, it appears that in oral fluid, as well as blood, opiates are detectable for significant periods of time and is significantly more sen-sitive than urine in the first two to four hours following opiate use
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Inter-individual dose/concentration relationship for methadone in hair
Paterson S.( 1 ). Cordero R.(1), McPhillips M.( 2 ), Carman S.m(1/Toxicology Unit, Imperial College of Science, Technology & Medicine, St Dunstan's Road, London W6 8RP, UK
(2) Substance Misuse Service, Brent, Kensington, Chelsea and Westminster Mental Health Trust, UK Hair samples were collected from sixty patients receiving long-term methadone maintenance, fifty were taking the drug orally and ten were receiving the drug by intravenous injection. The amount of methado-ne present in the hair samples was measured using methanolic extraction, derivatisation of the extracts with MTBSTFA followed by electron impact GC/MS operating in selected ion monitoring mode. The limit of detection for the assay was 0.15 ng/mg hair. The dose/concentration relationship for methadone in hair was investigated. No inter-individual correlation between prescribed dose and concentration of methado-ne in hair was observed.
\nnales de Toxicologie Analytique, vol. XIV, n° 3, 2002
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Rapid and sensitive cocaine analysis in hair using ChromatoProbe device
Pieraccini G.( , ), Moneti G.(1), Villanelli F.<2), Marsili R.i3), Chiarotti M.( 3 )(1) C.I.S.M. , Université di Firenze, Italy (2) Varían Italia, Leinl, Torino, Italy
(3) Istituto di Medicina Legale, Université Cattolica, Roma, Italy
We evaluated the performances of ChromatoProbe for the direct analysis of drug of abuse in a single hair sample. Starting from the work of Amirav and co-workers (1), we tested the Varían ChromatoProbe on actual hair samples that were previously analysed by SPME extraction and CG-MS detection (2,3) using d3-cocaine as internal standard.
Hair samples were taken from male Caucasian abusers, in which cocaine concentration was previously measured and ranging from 0,7 ng/mg to 13,7 ng/mg. Compared to the traditional method, the use of Chromatoprobe seems to offer a good extraction efficiency and, above all, the chance of revealing very low amount of cocaine in a single hair in a short time. A very limited sample preparation was necessary:
The hair was washed with MeOH, cut in 0,5cm length pieces and one of them inserted in the ChromatoProbe vial together with 20 pL of MeOH. The sample is then inserted in the temperature pro-grammable injection port via the ChromatoProbe and the GC run started. A short capillary GC column (Chrompack CPSil 8MS, 15 m x 0.25 mm, 0,12 film thickness) was employed and a total GC run time of 11 minutes. The instrumental sensitivity was enhanced working in positive Chemical Ionisation mode and adopting the MS/MS technique. A Varían Saturn 2200 was used. The quasi-molecular ion of cocaine ([M-H1]+, Th 304) was obtained using vapours of acetonitrile as reagent species: this specific ion was iso-lated and submitted to CID in resonant mode, recording the product ion spectrum in the range 145-306 Th.
Only one major fragment was obtained at 182 Th, together with less abundant fragments at 272 and 150 Th. The results obtained on positive hair samples will be shown, compared to «négative» hair drug free samples. As observed by Amirav and co-workers, the use of a polar solvent, preferably methanol, plays an important role in the extraction of cocaine from the hair matrix. A 5 to 10 fold increase of response was observed adding MeOH to the hair in the ChromatoProbe vial if compared to an «équivalent» sample without any solvent.
Very high signal-to-noise ratios were observed on the 182 Th ion trace also in hair containing less than 1 nanogram of cocaine for milligram, indicating that the limit of detection is probably in the order of at least 10-50 ppb.
1 - Wainhaus S.B.,et a l , J. Am. Soc. Mass Spectrom., 1998, 9 (12), 1311-1320.
2 - Strano-Rossi S. and Chiarotti M., / Analytical Toxicology 23, 7-11, 1999
3 - Chiarotti M. and Marsili R., Proceeding of the 22st International Symposium on Chromatography &
Electrophoresis. May 2000, Riva del Garda - Italy.
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