The Evaluation of Different Collection Methods for the Optimum Recovery of DNA from Bloodstains on Various Surfaces

This study compared the ability of cotton tip swabs and 4N6FLOQ™Swabs (Life Technologies, Carlsbad, CA) to collect dried bloodstains from various surfaces and recover the DNA transferred onto each swab. This study also examined whether swabs moistened with phosphate buffered saline (PBS) rather than distilled water (dH2O) provided any advantage in the recovery of DNA. The DNA yield; the quality of the Short Tandem Repeat (STR) profiles generated; and the ease of use were evaluated for the two swabs. The FLOQ™ swabs yielded the most DNA in the majority of the samples collected from each of the surfaces. There was no indication that PBS compared with dH2O provided any significant advantage in DNA yield and the quality of the STR profiles generated.