ABSTRACT
Human semen (seminal fluid) usually contains spermatozoa or sperm cells and the combined secretion of several accessory glands. In humans, seminal fluid contains several components besides spermatozoa, such as proteins (P30, prostate specific antigen, and flavin) and enzymes (acid phosphatase), which can be exploited for the presumptive and confirmatory identification of this body fluid. Visual examination with an alternate light source (ALS) will facilitate the detection of semen stains due to the flavin from the seminal fluid, which will fluoresce under ultraviolet light. Other presumptive tests exist for the detection of semen that are based on the presence of acid phosphatase (AP). However, since AP activity is not exclusive to human semen, confirmatory assays are necessary for the positive identification of semen.
