The Evaluation of Laser Diode Thermal Desorption ((LDTD) for High Throughput Analysis of Controlled Substances and Toxicology in Forensic Sciences

The National Institute of Justice (NIJ) is seeking applied research and development projects that will increase knowledge and understanding necessary to guide forensic science policy and practice or result in the production of useful materials, devices, systems, or 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 results in forensic laboratories that are often backlogged, creating budgetary and policy problems and potentially compromising investigations. This project will evaluate the applicability of the laser diode thermal desorption (LDTD) ionization source across multiple mass spectrometry (MS) platforms, for the high-throughput quantitative analysis of controlled substances and drug toxicology in forensic laboratories. This novel technology has the potential to significantly decrease both analysis time and per-sample cost. The LDTD source coupled with MS has demonstrated its applicability in other scientific areas by providing data comparable to traditionally used instrumentation, such as liquid chromatography-tandem mass spectrometry (LC-MS/MS), in less than half of the time without the need for commonly used laboratory consumables such as analytical columns. Preliminary analysis conducted at RTI International and Phytronix Technologies, Inc. indicates that LDTD-MS/MS produces results comparable to LC-MS/MS in the analysis of postmortem samples with minimal sample preparation (saving labor and improving sample integrity) and a reduction in analysis from 11 minutes to 11 seconds per sample. These results warrant further investigation and demonstration of the applicability and validity of this technique in forensic laboratories. We propose a staged strategy to evaluate LDTD coupled with triple quadrupole (QQQ) and time-of-flight (TOF) MS, with the investigation of other mass spectral platforms if time and funding allow. The LDTD source will be used to analyze drugs of interest, beginning with optimizing methanolic drug standards (e.g., designer drugs, controlled substances) followed by analyzing drugs in urine, blood, and multiple drug formulations (e.g., powders, plant material). We will partner with Phytronix Technologies, Inc.; Overbook Scientific, Inc., who will provide instrumentation and method development consultation; and various forensic laboratories who will provide archived case samples for analysis. The Center for Forensic Sciences (CFS) at RTI has a unique relationship with many forensic laboratories and organizations across the country, which will allow for wide dissemination of developed methods to the forensic toxicology community. This new analytical technique has the potential to affect policy and practice in forensic laboratories by minimizing sample preparation, improving specificity and sensitivity in comparison to current quantitative technologies, decreasing analytical costs, and ultimately reducing laboratory backlogs. 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. 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. ca/ncf