Our group blends fundamental studies in analytical chemistry with applied deliverables in the forensic and materials sciences. We are interested in understanding the (bio)chemical properties of common types of physical evidences and traces deposited at crime scenes and how they persist in the environment. We primarily characterize polymeric films made from rheologically complex materials using a suite of spectral and imaging techniques. Typically, these are generated from droplets of blood and other natural or synthetic biofluids.


Molecular characterization of films created from complex (bio)fluids


We use a suite of spectral techniques, including Raman, FTIR, UV-Vis and hyphenated mass spectrometry, to characterize the molecular composition of films created from blood and other polymeric liquid materials. A highlight of our research is the use of applied statistics and high-resolution mass spectrometry in collaboration with Trent University's Water Quality Centre.  We are also interested in understanding the degradation mechanics of these films and how they change over time. For example, we are currently combing methodologies in analytical chemistry and applied genetics to better predict the deposition time of bloodstains, and, eventually, other biofluids.

 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 properites of blood. Some materials are tailoured 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 me!

 Thank you: We acknowledge the support of the Natural Sciences and Engineering Research Council of Canada (NSERC).

© Copyright Theresa Stotesbury 2020