TY - JOUR PY - 2011// TI - LC-MS-MS method for simultaneous determination of THCCOOH and THCCOOH-glucuronide in urine: Application to workplace confirmation tests JO - Forensic science international A1 - Felli, M. A1 - Martello, S. A1 - Chiarotti, M. SP - 67 EP - 73 VL - 204 IS - 1-3 N2 - Cannabis is the one of the most frequently detected drug in workplace drug testing and in cases of driving under influence of drugs, and there is a greater demand for sensitive, rapid and reliable methods for confirming the presence of this drug in biological samples. This paper describes an LC-MS-MS procedure for direct analysis of cTHC and cTHC-glucuronide in urine, without hydrolysis of the samples or derivatisation. The sample preparation is very simple and consist only in a dilution of urine with methanol 1:1 (v/v) after adding the deuterated internal standard (cTHC-d3); then 10μl of the final solution is injected in LC-MS-MS. Chromatographic separation was performed using a reversed-phase column and gradient elution with 0.01% formic acid/acetonitrile/methanol and two MS-MS transitions for each substance were monitored. The method was fully validated and proved to be accurate (RSD <15%), precise (intra-day CV <10%) and sensitive with a limit of detection (LOD) of 5ng/ml for both the compounds studied. Linearity was tested in the range 5-1000ng/ml and the values of R(2) resulted >0.99. The developed method was applied to several authentic samples of urine which tested positive in the immunoassay screening and 98% of them was confirmed.

Language: en

LA - en SN - 0379-0738 UR - http://dx.doi.org/10.1016/j.forsciint.2010.05.004 ID - ref1 ER -