Semen Identification through the Detection of Fructose Levels

Voiceover

Presenter(s)

Emily Chadwick

Abstract or Description

Body fluids such as semen, blood, saliva, urine, and vaginal fluid are commonly found at crime scenes and can give investigators insight into what occurred. In order to differentiate body fluids, presumptive and confirmatory tests have been developed and are used to determine the composition and identity of a body fluid. Currently, the acid phosphatase test is used to detect semen. However, vaginal fluid can also contain acid phosphatase which can lead to a false positive or negative test result causing problems in sexual assault cases. Although semen contains acid phosphatase, it also contains a high concentration of fructose. The purpose of this study was to determine if the concentration of fructose can be used as a detection method for semen. In this study, the concentration of fructose in semen, blood, urine, and vaginal fluid samples were determined by identifying the amount of free fructose in each sample with the use of a fluorometric assay. This fluorometric assay takes the free fructose in the samples and converts it enzymatically to β-glucose which determines the concentration of fructose present in the sample. Results showed that the concentration of fructose in a liquid sample was able to be quantified using the fluorometric assay. Data showed fructose has a high concentration in semen. It was determined fructose concentrations could be quantified using dried samples on cotton swabs. If this method of identifying semen is found to be viable it will benefit sexual assault casework.

Mentor

Pamela Marshall, Ph.D.