Towards Onsite Age Estimation of Semen Stains Using Fluorescence Spectroscopy
Nihad Achetib,
Caren C. Leemberg,
Mathijs M. P. Geurts,
Paul R. Bloemen,
Richard M. van den Elzen,
Maurice C. G. Aalders,
Annemieke van Dam
Affiliations
Nihad Achetib
Department of Biomedical Engineering and Physics, Amsterdam University Medical Centers (UMC), Location AMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
Caren C. Leemberg
Department of Biomedical Engineering and Physics, Amsterdam University Medical Centers (UMC), Location AMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
Mathijs M. P. Geurts
Department of Biomedical Engineering and Physics, Amsterdam University Medical Centers (UMC), Location AMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
Paul R. Bloemen
Department of Biomedical Engineering and Physics, Amsterdam University Medical Centers (UMC), Location AMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
Richard M. van den Elzen
Department of Biomedical Engineering and Physics, Amsterdam University Medical Centers (UMC), Location AMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
Maurice C. G. Aalders
Department of Biomedical Engineering and Physics, Amsterdam University Medical Centers (UMC), Location AMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
Annemieke van Dam
Department of Biomedical Engineering and Physics, Amsterdam University Medical Centers (UMC), Location AMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
The age estimation of biological traces is one of the holy grails in forensic investigations. We developed a method for the age estimation of semen stains using fluorescence spectroscopy in conjunction with a stoichiometric ageing model. The model describes the degradation and generation rate of proteins and fluorescent oxidation products (FOX) over time. The previously used fluorimeter is a large benchtop device and requires system optimization for forensic applications. In situ applications have the advantage that measurements can be performed directly at the crime scene, without additional sampling or storage steps. Therefore, a portable fiber-based fluorimeter was developed, consisting of two optimized light-emitting diodes (LEDs) and two spectrometers to allow the fluorescence protein and FOX measurements. The handheld fiber can be used without touching the traces, avoiding the destruction or contamination of the trace. In this study, we have measured the ageing kinetics of semen stains over time using both our portable fluorimeter and a laboratory benchtop fluorimeter and compared their accuracies for the age estimation of semen stains. Successful age estimation was possible up to 11 days, with a mean absolute error of 1.0 days and 0.9 days for the portable and the benchtop fluorimeters, respectively. These results demonstrate the potential of using the portable fluorimeter for in situ applications.
