Comparison of p30 and acid phosphatase levels in post-coital vaginal swabs from donor and casework studies.

The application of p30 detection to casework analysis of seminal traces on vaginal swabs is reported and compared with the levels of acid phosphatase determined. A simple crossed-over immunoelectrophoresis system was used for batch identification of swab extracts using a commercially obtained anti-p30 serum. Positive p30 results were obtained in less than 20% of the casework swab extracts, but they provide conclusive proof of the presence of semen which is a substantial advantage over the quantitative determination of acid phosphatase.