Dried Blood Spot Analysis as an Emerging Technology for Application in Forensic Toxicology

The National Institute of Justice (NIJ) is seeking applied research and development projects in the area of forensic science that will result in useful materials, devices, and systems or provide methods that have the potential for forensic application. Hundreds of thousands of controlled substances and drugs of abuse are analyzed in forensic laboratories each year and are submitted as evidence in judicial cases. This abundance of drug-related cases can be a burden to laboratories if they are not able to analyze samples in a timely manner. Dried blood spot (DBS) analysis, which has been well-established in the area of clinical testing for decades (e.g. screening of neonates for phenylketonuria) is a technique that has the potential to alleviate some of this burden on forensic laboratories. DBS has the potential to1) increase sample stability allowing samples to be stored for longer periods of time; 2) create a safer work environment for sample collectors and analysts due to the small sample volume requirement; 3) allow first responders to acquire a finger prick sample at the scene of a crime (e.g., drug-facilitated sexual assault) without waiting for subsequent collection at the hospital; and 4) significantly reduce costs in the area of transportation of DBS cards compared to traditional specimens. We propose to evaluate the use of DBS for application in forensic laboratories. DBS samples will be analyzed using both laser diode thermal desorption (LDTD) and an Agilent automated card extraction (AACE) system coupled to triple quadrupole mass spectrometers to determine the suitability of these systems for forensic DBS analysis. Specifically, we will determine if DBS analysis 1) is sensitive enough for quantitation of drugs of abuse, 2) produces results comparable to traditional drug analysis, 3) increases the stability of certain drugs of abuse, and 4) will result in cost and time savings when compared to traditional methods of analysis. RTI International is currently evaluating the applicability of the high-throughput LDTD ion source coupled with tandem mass spectrometry technology for the analysis of drugs of abuse (NIJ-2012-R2-CX-K004). The technology is showing promising results, but suffers from the potential for sample mix up. The introduction of an automatic card extraction system allows for online extraction capabilities that decrease the potential for errors during manual extraction steps, while maintaining strict sample tracking. The success of DBS for the analysis of drugs of abuse, coupled with these novel technologies, has the potential to decrease the amount of time needed for sample analysis, which will impact the rate at which cases can be processed in the judicial system. The unique relationship that RTI Internationals Center of Forensic Sciences has with many organizations and forensic laboratories across the country will allow for wide dissemination of developed methods to the forensic toxicology community. In addition to submitting regular financial reports, a semi-annual progress report, and a final report to NIJ, we plan to publish the study results in prominent forensic toxicology journals and present the results at the annual meetings of leading forensic organizations. RTI currently provides web-based training to forensic and ancillary professionals in all 50 U.S. states and other countries. This existing webbased technology will continue to be used to circulate the findings of this research. All analytical data, along with prepared financial, semi-annual progress, and final reports, will be made available for archiving by the NIJ Data Resource Program.
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