Akademik Veri Yönetim Sistemi
JOURNAL OF POLYTECHNIC-POLITEKNIK DERGISI, 2023 (ESCI)
In forensic science laboratories and crime scene investigation applications, analyses of discovered stains are crucial. In order to carry out an effective investigation by determining the variables related to the crime and those involved in the event, it is necessary to analyze the samples quickly, in small quantities, and even in the form of mixtures. Therefore, it is of high importance to analyze evidential materials with non-destructive, fast, cost-effective techniques. Spectroscopic methods have advanced significantly in recent years with important developments in light detectors and take place among forensic procedures. This study focused on Raman and Surface Enhanced Raman Spectroscopy (SERS) for detecting pure urine mixed stains. In order to reduce the fluorescence effect caused by the matrix components of the urine, dilution was made and Raman analyses were performed for four different concentrations. It was observed that as the concentration decreased, the noise ratio decreased and the peaks became more pronounced. A simulated crime scene containing stains of pure urine, diluted urine (1:2, 1:4, and 1:8), apple juice, mixture (apple juice and different concentrations of urine), and gold nanorod/silver nanoparticle doped mixtures were created to check the detectability of urine from a complex crime scene. Despite the low peak intensity in the Raman spectrum, the presence of urine was still detectable. The SERS spectrums of the stains obtained from the simulated crime scene were examined first with the addition of gold nanorods and subsequently with the addition of silver nanoparticles. Silver nanoparticles, known for their strong plasmonic properties, were found to provide greater signal enhancement compared to gold nanorods.