Résumé
This study was conducted to evaluate the relationship between the age of the dried human bloodstains and the degree of detectability of morphine and phenobarbitone present in bloodstains. Detection of the drugs was studied in bloodstains at different time intervals [1, 14 days 1, 2, 3, 4, 5 months] by using thin layer chromatography [TLC] and enzyme multiplied immunoassay [EMIT]. Furthermore, the effect of storage temperature [25C and 20C] on detectability of these drugs was investigated. The results showed that both phenobarbitone and morphine could be detected by TLC from recent and old blood stains up to 5 months at both 25C by using EMIT, the percentages of both phenobarbitone and morphine concentrations were 48.39% and 82.59%, respectively, after 5 months of storage at room temperature [25C]. Thus, the decrease in morphine concentrations was less marked than that of phenobarbitone indicating that morphine was more stable in bloodstains. On the other hand, storage of blood stain samples at-20C showed slight insignificant variation in the concentrations of both phenobarbitone and morphine at all the time intervals up to 5 months. It became 98.98% and 98.80%, respectively, after 5 months. Thus, storage of bloodstains at 20C had a stability effect on the tested drugs. Statistical regression equation was used to predict the concentrations and percentages of both phenobarbitone and morphine in the dried bloodstains provided that the age of bloodstain is known at the time of assay