Evaluation of the effect of Problem Based Learning course
DOCUMENT
Evaluation of the effect of Problem Based Learning course
DOCUMENT
Non-invasive, rapid, on-site detection and identification of body fluids is highly desired in forensic investigations. The use of fluorescence-based methods for body fluid identification, have so far remain relatively unexplored. As such, the fluorescent properties of semen, serum, urine, saliva and fingermarks over time were investigated, by means of fluorescence spectroscopy, to identify specific fluorescent signatures for body fluid identification. The samples were excited at 81 different excitation wavelengths ranging from 200 to 600 nm and for each excitation wavelength the emission was recorded between 220 and 700 nm. Subsequently, the total emitted fluorescence intensities of specific fluorescent signatures in the UV–visible range were summed and principal component analysis was performed to cluster the body fluids. Three combinations of four principal components allowed specific clustering of the body fluids, except for fingermarks. Blind testing showed that 71.4% of the unknown samples could be correctly identified. This pilot study shows that the fluorescent behavior of ageing body fluids can be used as a new non-invasive tool for body fluid identification, which can improve the current guidelines for the detection of body fluids in forensic practice and provide the robustness of methods that rely on fluorescence.
MULTIFILE
Fluorescence microscopy is an indispensable technique to resolve structure and specificity in many scientific areas such as diagnostics, health care, materials- and life sciences. With the development of multi-functional instruments now costing hundreds of thousands of Euros, the availability and access to high-tech instrumentation is increasingly limited to larger imaging facilities. Here, we will develop a cost-effective alternative by combining a commercially available solution for high-resolution confocal imaging (the RCM from confocal.nl) with an open-hardware microscopy framework, the miCube, developed in the Laboratory of Biophysics of Wageningen University & Research. In addition, by implementing a recent invention of the applicant for the spectral separation of different emitters, we will improve the multiplexing capabilities of fluorescence microscopy in general and the RCM in particular. Together, our new platform will help to translate expertise and know-how created in an academic environment into a commercially sustainable future supporting the Dutch technology landscape.
