Social and Behavioral Sciences Commons^™

Performance Of A Dna And Protein Co-Extraction With Trypsin In Comparison To Two Proteinase K Based Dna Extraction Methods, Dinura A. Gunatilake

Student Theses

Effective DNA extraction methods are important for forensic applications. The main goal of this experiment was to determine if a newly developed trypsin based protein/DNA co-extraction method applied to contact traces would yield comparable results to a commercial Proteinase K method (QIAamp DNA Investigator Kit) and a Chelex extraction method with Tween 20 used in forensic laboratories. This was tested on 20 sets of sebaceous fingerprints on glass slides.

The results of this study demonstrate the trypsin co-extraction method yielded the highest amount of DNA. In the first comparison, the mean total DNA yields for the trypsin-co extraction method and …

Semi-Quantitative Detection Of Signature Peptides In Body Fluids By Liquid Chromatography Tandem Mass Spectrometry (Lc-Ms/Ms), Tebah N. Browne

Student Theses

This study covers a modified semi-quantitative approach for liquid chromatography mass spectrometry (LC-MS/MS) signature peptide detection for body fluid identification. Peptide concentrations were measured based on synthetic peptide standards. Samples were processed with varying trypsin digestion and purification protocols, including a three-hour trypsin digestion and Microcon membrane filtration. The Microcon filtration method generates polymerase chain reaction (PCR) compatible DNA and peptide fractions that can be analyzed without any further purification. Preliminary validation tests covered stains on different substrates, semen/ saliva mixtures, minimum sample volume, and repeatability. All signature peptides in the multiplex were present at different concentrations and varied amongst …