Development of a harmonised method for the profiling of amphetamines V: Determination of the variability of the optimised method

This paper is the fifth in a series of six in relation to the development of a harmonised method for the profiling of amphetamine [L. Aalberg, K. Andersson, C. Bertler, H. Borén, M.D. Cole, J. Dahlén, Y. Finnon, H. Huizer, K. Jalava, E. Kaa, E. Lock, A. Lopes, A. Poortman-van der Meer, E. Sippola, Development of a harmonised method for the profiling of amphetamines I. Synthesis of standards and compilation of analytical data, Forensic Sci. Int. 149 (2005) 219-229; L. Aalberg, K. Andersson, C. Bertler, M.D. Cole, Y. Finnon, H. Huizer, K. Jalava, E. Kaa, E. Lock, A. Lopes, A. Poortman-van der Meer, E. Sippola, J. Dahlén, Development of a harmonised method for the profiling of amphetamines II. Stability of impurities in organic solvents, Forensic Sci. Int. 149 (2005) 231-241]. The third paper [K. Andersson, K. Jalava, E. Lock, L. Aalberg, Y. Finnon, H. Huizer, E. Kaa, A. Lopes, A. Poortman-van der Meer, M.D. Cole, J. Dahlén, E. Sippola, Development of a harmonised method for the profiling of amphetamines III. Development of the gas chromatographic method, Forensic Sci. Int., in press] dealt with the optimisation of the gas chromatographic and detection methods whereas the fourth paper [K. Andersson, K. Jalava, E. Lock, Y. Finnon, S. Stevenson, L. Aalberg, H. Huizer, E. Kaa, A. Lopes, A. Poortman-van der Meer, M.D. Cole, J. Dahlén, E. Sippola, Development of a harmonised method for the profiling of amphetamines IV. Optimisation of sample preparation, Forensic Sci. Int., in press] concerned the optimisation of the extraction method prior to GC analysis. This paper is a study of the optimised method in order to determine its stability. Investigations of within and between day variations were carried out in four laboratories. Moreover, variations between laboratories were also determined. Both flame ionisation detector (FID) and MS detection were used. One laboratory studied nitrogen-phosphorous detector (NPD) detection as well. For this task, 12 batches of amphetamine were prepared. Six of them were synthesised via the Leuckart route, three via the nitrostyrene route and three via the reductive amination route [A.M.A. Verweij, Impurities in illicit drug preparations: amphetamine and methamphetamine, Forensic Sci. Rev. 1 (1989) 2-11]. Taking into account all studied target compounds and the average results from four laboratories, the within day variation was around 6% for FID and 5% for MS, the between days variation was around 10% for FID and 8% for MS. For NPD detection, within day variation was 5% and between days variation 9% (only one laboratory). Finally, the inter-laboratory variation was about 12% for FID (four laboratories) and 10% for MS (three laboratories).     

血中毒鼠强的固相萃取和GC-NPD法测定

目的 研究人全血中毒鼠强的固相革取(SPE)。方法 用Bond Elute C18固相萃取柱萃取,GC-NPD检测,以甲基对硫磷为色谱内标(CS)。结果 全血中加标0.5μg/ml,毒鼠强回收率为92.5％,变异系数2.3％(CV,n=4)。在0.5～10μg/ml的浓度范围内,线性相关系数为0.9994。检出限(S/N=3)和定量限(S/N=10)分别为6ng/ml和20ng/ml。同一根萃取柱连续使用6次未见性能明显下降(CV=3.6%)。结论 本文方法适用于毒鼠强中毒的全血测定。     

尿素中毒的检验

目的　建立了用气质联用法定量分析尿素的方法。　方法　采用传统滴定分析和气质联用定性定量检验对照分析。　结果　在 0 1μg～ 5 0 μg范围内 ,该方法有较好的线性 (r >0 9976 )。　 结论　该方法准确、快速 ,适用于尿素的定量分析