Washington, DC - The rapid spread of designer drugs has introduced significant identification challenges to the forensic science community. This webinar discusses how Mass Spectrometry and the “Hybrid Search” can be used to get a head start on identifying novel opioids.
Mass spectral library searching is an important tool in seized drug identification. It allows an analyst to identify a drug by comparing the experimental spectrum to a reference set of spectra for known compounds. The primary limitation of conventional library search algorithms is the requirement that the mass spectral database contain a representative spectrum of the query compound. This limitation is particularly restrictive when novel molecules are synthesized more rapidly than they can be added to mass spectral libraries. In this presentation, we briefly discuss conventional library searching and in more detail the new “Hybrid Search” method that combines fragment-ion and neutral-loss matching when computing similarity match factors.
The search algorithm generates high scores for compounds that differ by a single chemical modification yet share similar fragmentation behavior (chemical analogs). Accordingly, if a chemical does not have a spectrum in the library, it can still be correctly classified given that its chemical analogs are contained in the library. Following a detailed description of the algorithm and its software implementation, numerous example applications are presented, including the identification of novel fentanyl analogs.
Detailed Learning Objectives: The goal of this seminar is to provide the audience with an overview of one of the important analytical chemistry techniques in drug identification – Mass Spectral Library Searching. Completion of the webinar should allow attendees to:
- Broadly explain the principles of mass spectral library searching and uncertainty involved with search-based identification.
- Understand the limitations of conventional mass spectral library searching for novel compounds such as designer opioids.
- Apply the “Hybrid” mass spectral library search method for compound classification.
Funding for this Forensic Technology Center of Excellence event has been provided by the National Institute of Justice.