Analysis of illicit drugs in dried blood spots using LC-MS/MS method

The blood that obtained by opening a vascular access is considered as golden standard for anlysis of illicit drugs. However, this practice brings restrictions and/or difficulties in its wake such as high storage and transport costs, being invasive, need for health proffessional to obtain sample and risk of transmission of blood borned infections. At this point, in order to overcome the difficulties that is brought by conventional blood sampling methods, Dried Blood Spot (DBS) is appeared as a good alternative. By this study, ability of dried blood spots, which is derivered from venous blood, to represent the whole blood is going to be researched in terms of detection of illicit drugs. Due to obtained data, it is aimed to determine how useful DBS is and what advantages/disadvantages DBS brings on in forensic practices. In this study, in the first instance, validation of method was acquired. In this context, recovery rates of DBSs, which were prepared by injecting known amounts of substance metabolites into the blank blood, were measured. After determining recovery rates, in order to evaluate usefulness on real cases, intravenous blood obtained with vascular access from volunteers applied to Forensic Toxicology Laboratory of Çukurova University Department of Forensic Medicine, were used. Samples belong to ones who are verified not using any drugs were not included in the study and comparison was only done over subjects whose venous blood comes out positive. Sampling process had continued untill positive sample count reached 100. Enough recovery rates were not achieved for four of fourteen drugs which are included in the experiment. Altough acquired data for one of remaining ten drugs were significant, they are assessed as not prone because limits of detection and quantifcation were high. The statistical data which is found out after comparison of DBS and venous blood are found to be significant for the rest nine drugs. Developed DBS method was applied on real cases, too. Obtained results show that this methot is not ready to replace routine application and there is need to be improved futher. In this regard, it is came up with that DBS method can be used instead of whole blood in forensic practices and advantages that is brought by DBS can be utilized, by means of working on this issue little more. By this way, both several conveniences in terms of execution will be provided and execution, storage and transportation costs of analysis of illicit drugs will decrease significantly. Furthermore, the data that obtained from this study and further works that will be carried over on this topic will ensure practical, rapid and reliable sampling on crime scenes and fields out of laboratory. Key Words: Forensic Toxicology, Dried Blood Spot, Narcotics, Illicit Drugs, Venous Blood.