Maximizing semen extraction from sanitary pads by chemical and shredding treatments

Evidence of sexual aggression may be obtained from superabsorbent polymer (SAP) sanitary pads, which are used by forensic laboratories for semen evaluation. Semen can be extracted from their upper layers, which are free of SAPs. However, our previous results showed a need to optimize the protocol for semen analysis by considering its extraction from the lower core, often composed of sodium polyacrylate SAPs. SAPs generate a hydrogel, which traps the cellular components, hindering the possibility of obtaining cells and hence their genetic material. Simple filtration has been tried previously, but further maximization by application of a treatment has never been attempted. In this paper, we compare both chemical and physical shredding treatments for maximizing gel-trapped sperm and male cell DNA recaptures from hygienic superabsorbent substrates in sanitary pads, panty-liners or diapers. Our findings suggest that the lower core should be treated to induce a dewaterisation of the SAP hydrogels in order to maximize the extraction of bodily fluids.