Midwest Forensics Resource Center 2008 Funded Projects
Organic impurity profiling of illicit synthetic drug tablets aims to identify similarities among tablets. Similar impurity profiles indicate a common production method, and similar levels of the same impurities potentially indicate common production laboratories. In this research project, headspace solid phase micro-extraction (HS-SPME) procedures for the extraction of organic impurities from illicit MDMA (‘ecstasy’) tablets are developed and compared with conventional liquid-liquid extraction procedures, in terms of the number and level of impurities extracted. HS-SPME is rapid, requiring no solvent and yielding selective extraction of impurities. Hence, HS-SPME is a promising extraction procedure that offers attractive advantages over conventional procedures.
The use of steganographic software for hiding information in image files for illicit purposes is becoming more widespread. While steganalysis algorithms are abound in the academic literature, there are few software programs that address the needs of localpolice departments who perform computer forensic functions for steganalysis. This project extends the proof-of-concept established on the use of an artificial neural network for wavelet steganalysis in an earlier study. Specific aims are to enhance the capabilities of the software and to make it available for practical use in computer forensics.
Although DNA can be associated with a human bite, it is not always recovered. In such cases, an analysis of bitemark evidence is required. Yet, forensic odontologists are under attack for lacking a scientific basis for their analysis. This project studies the ability to scientifically quantify the occurrence of special dental characteristics and error rates in the analysis of bitemarks. Using six measurements, a 3D quantification technique and 400 samples, a database is created that may provide the criminal justice system with the beginning of a tool and the hard science for objective statement of probability, in either exculpating or incriminating a suspect from patterned injuries cause by human teeth.
Bloody impressions are of great importance to the forensic community as they are frequently encountered at crime scenes. Impression evidence in blood cannot always be removed from the crime scene for analysis in a laboratory setting. Because of this, many potentially identifiable impressions can only be photographed and not enhanced, thereby complicating the latent print identification process. In an earlier study, a lifting strip containing titanium dioxide was successful in lifting and enhancing bloody fingerprints from several non-porous and semi-porous surfaces of contrasting colors. This study improves upon the methods used to lift bloody palm prints, foot prints, and footwear impressions, in addition to bloody fingerprints from porous, semi-porous, and non-porous surfaces.
This project is a continuation of previously funded work titled “Ultra-Fast Gradient Elution Reverse-Phased HPLC with Diode-Array Detection.” That activity improved both the speed and selectivity of older HPLC methods through a combination of precise retention measurements and chemometric analysis of the spectro-chromatograms. In the currently funded two projects, several enhancements are examined. First, to improve selectivity, three HPLC phases are studied to find the pair that is most orthogonal so as to dramatically reduce the number of indistinguishable analytes. Second, to improve speed, recently commercialized very small stationary phases that use the “core-shell” concept are applied. Finally, the sensitivity and specificity of the new methodology is studied by evaluating real samples whose compositions have been pre-assessed by accepted confirmatory methods, especially LC-MS.