As submitted by the proposer:
Currently, the methods used to identify body fluids in forensic investigations are either presumptive or destructive to the evidence. A universal test that could identify any body fluid at a crime scene without destroying it would be an extraordinary breakthrough in forensics. Our research group has developed a novel method to identify body fluid traces using Raman spectroscopy and chemometrics. The proposed research has two overall goals; to advance and validate the developed method. Method advancement will be accomplished by developing new capabilities for body fluid characterization. Raman spectra will be collected semen, sweat, and saliva donors, and used to build chemometric classification models to differentiate donors according to race and gender. All models will be externally validated with test datasets. Method validation will be performed by testing the current protocols with a handheld Raman instrument, and by establishing the limit of detection. Body fluids will be analyzed using a handheld Raman spectrometer and the spectra collected will be used to test the current chemometric models, built with spectra collected by bench top instruments. The handheld spectrometer will be provided by our collaborators at the Defense Forensic Science Center at the Department of the Army. This investigation will inform us whether or not the current method is applicable to data collected by on-field instrumentation. Any necessary adjustments will be made so that the method is not dependent on the instrumentation used. Raman spectra from incredibly small droplets of blood, semen, and saliva will be collected to determine the methods limit of detection. Sample preparation will be carried out with the help of our partners at the State University of New York Polytechnic Institutes College of Nanoscale Science and Engineering. The spectra will then be tested against the current identification methods in order to determine if the body fluids can be detected. After our experimentation, the samples will then be submitted to our collaborators at the New York State Police Crime Lab System for DNA analysis. This will allow us to confirm whether or not Raman laser irradiation damages the DNA contained within the body fluid traces. Achieving these two goals will help to improve the current method and move it one step closer to practical implementation. All results from the proposed research will be submitted to peer-reviewed publications and included in semi-annual reports to the NIJ. The data that is collected will be archived according to NIJ requirements.
This project contains a research and/or development component, as defined in applicable law.