Pulse Lavage System (PLS) versus forensic wet-vacuum collection of biological material.

Abstract

Wet-vacuum collection of forensic biological material has been shown to recover greater total DNA yields compared to traditional methods, such as wet swabbing. The Pulse Lavage System (PLS), an orthopedic surgical instrument, was evaluated in comparison to a forensic wet-vacuum device for the DNA collection and recovery of diluted bloodstains from seven substrates of varying porosity. Three different PLS models were evaluated, and each model yielded DNA concentrations which were comparable to the forensic wet-vacuum system, recovering 79-99% relative to the wet-vacuum, which were overall not statistically different. Our results suggest that the PLS, though intended for medical use, has the potential to serve as an affordable alternative to the forensic wet-vacuum system. However, additional evaluation and modification to the PLS collection method may be warranted for complete optimization.