Comparison of laser and high-intensity quartz arc tubes in the detection of body secretions

The detection capabilities of both laser and high-intensity quartz arc tubes were evaluated. The Spectra-Physics Model 171-19, 18-W argon ion laser and Laser Sonics Model CS-2, 200-mW air-cooled argon ion laser were compared with Payton Scientific's Luma-Print, high-intensity quartz arc tube. The light sources were evaluated as to their detection limits for various biological stains. The stains that were evaluated had been made during prior research. These stains had been stored at room temperature for approximately two years. The stains were a serial dilution made from semen, saliva, and sweat specimens and were examined using both laser light sources and the high-intensity quartz arc tube. The advantages and disadvantages of each light source in relationship to its initial costs and potential use in forensic serology are discussed.