Document Title: Enhanced Forensic Mass Spectrometry Methods (original) (raw)

As stated in the NIJ sponsored report entitled, Forensic Sciences: Review of Status and Needs, "Methods research, development, testing, and evaluation (RDT&E) activities are vital to the provision of effective forensic science laboratory services." The main goal of this proposal is to develop a better, faster and potentially less expensive method for confirming the identity of chemicals of forensic interest, and to facilitate the broad dissemination of the method for use by forensic chemists and toxicologists. While mass spectrometric methods are used for the identification of chemicals, especially of controlled substances, most require chromatographic sample purification steps. Our objective is to develop simple, robust, rapid, sensitive, specific and cost effective direct mass spectrometric methods for the identification of controlled and toxic substances that minimize sample clean-up procedures. Enhanced MS methods relevant to the practice of forensic chemistry and toxicology are anticipated from this proposal. Single stage mass spectra continue to be the cornerstone of chemical identification. Methods that apply multistage mass spectra, such as MS/MS, are well established. MS/MS/MS (MS 3) is available on competitively priced ion trap mass spectrometers. The application of further stages of fragmentation provide increased confidence in structure assignments of chemicals plus the potential for decreased need for extensive sample preparation. Multistage MS provides identification methods that take less time to perform, decrease hazardous solvent use, obviate derivatization steps, and provide chemical confirmation of substance identity. We developed methods that utilize MS 3 techniques and published the results. Ion suppression concerns were addressed through the use of stable isotope labeled internal standards.