Characterization and Classification of Sexual Assault Lubricants using Direct Analysis in Real Time-Time of Flight Mass Spectrometry

• NCJ Number: 254402
• Date Published: August 2019
• Author(s): Candice Bridge
• Agencies: NIJ-Sponsored
• Publication Type: Grant Report
• Award: Characterization and Classification of Sexual Assault Lubricants using Direct Analysis in Real Time at Time of Flight Mass Spectrometry

Annotation

This is the Final Summary Overview of a research project that sought to capitalize on the ease of use and the high mass resolution of the direct analysis in real time-high resolution mass spectrometry (DART-HRMS) instrument to design a rapid screening technique and a classification scheme for unknown lubricant samples.

Abstract

This method was compared to current techniques such as gas chromatography-mass spectrometry (GC-MS) and Fourier transform infrared spectroscopy (FTIR). The classification schemes developed will be provided in the forensic lubricant database known as the Sexual Assault Lubricant Database. The project included the comprehensive examination of lubricant samples, so as to understand and identify similarities and differences among samples in creating classification schemes for unknown lubricant samples. This report summarizes analytical methods, data analysis, and the database design. The project succeeded in developing validated instrumental methods for analyzing lubricants of various bases (silicone-based, water-based, oil-based, edible, condom, and personal hygiene products), using each instrument. It determined which methods extract the most components, particularly for GC-MS, that will best discriminate samples. Many of the spectra for GC-MS did not produce any actual spectra, regardless of extraction method. DART-HRMS, however, was able to detect many of the components that GC-MS was not able to detect. FTIR was useful for determining the primarily lubricant base. Overall, this project has produced a new database and associated classification schemes that can be used in the analysis of unknown sexual lubricant samples collected in sexual assault cases. A listing of the project’s scholarly products is included.