Our research group blends forensic and analytical chemistry with materials science. We are interested in understanding the biomolecular properties of common types of physical evidence deposited at crime scenes and how they persist in the environment. We characterize these materials using a suite of spectral and imaging techniques. Our group focuses on blood and synthetic biofluids.
Biomolecular characterization of films created from complex (bio)fluids
We use a series of spectral and imaging techniques to characterize the molecular composition of films created from blood and other polymeric liquid materials. Currently, we on a quest to create better models to determine the Time Since Deposition (TSD) of bloodstains, and, eventually other biofluids. In forensic science scenarios, bloodstained evidence is often collected and analyzed only to address the questions of “who” (through source identification by linking DNA to an individual) and “how” (mechanistically by bloodstain pattern analysis). The “when” (time since deposition, TSD) and “what else” (new and improved techniques) is often overlooked and can provide critical medico-legal information for these investigations. In this research we are exploring how forensic chemistry, applied genetics, applied statistics and high-resolution mass spectrometry can all contribute to TSD estimations.
Bloodstain and other non-Newtonian fluid formation mechanics
We are currently interested in understanding bloodstain formation mechanics as they relate to crime scene investigation. We simulate a variety of mechanisms of bloodshed and use image processing techniques to understand how stains and patterns form across surfaces. Our work typically features the use of high-speed video analysis, as these events can take place in sub-second conditions. We care about understanding how complex liquids generate droplets when impacted and how these droplets spread and splash across a variety of surfaces. Currently, we are in researching how passive drip stains form on cold (ice, snow) surfaces.
Standard reference materials for forensic science practices
In these research projects we put our fundamental knowledge to practice and create (commercial) materials for the industry. To date, our research group has created whole mammalian blood analogues that mimic forensically relevant physico-chemical properties of blood. Some materials are tailored to mimic the physical pattern formation mechanics of blood, others will react with common detection reagents. We are currently working on developing DNA bound materials, and ones that are biocompatible and created with green chemistry considerations. If you are an end-user of such projects or have projects in mind, please feel free to contact Theresa!
Check out our #RSCPoster 2022 feature, created and produced by Mandie Orr:
Thank you: We acknowledge the support of the Natural Sciences and Engineering Research Council of Canada (NSERC).