Volume 33, Issue 6 (November 1988)
Fluorescence of Petroleum Products III. Three-Dimensional Fluorescence Plots of Petrolatum-Based Products
A high degree of association between known and unknown specimens of petrolatum-based lubricants, which occur as evidence in criminal sexual assault cases, can be demonstrated by using three-dimensional fluorescence spectroscopy (3-D fluorescence). Fifteen petrolatum-based products, five mock cases, and two cases provided by the Michigan State Police Crime Laboratory are analyzed and compared using this technique. Controls are run to eliminate interfering substances and to insure proper technique. Three-dimensional plots of excitation, emission, and synchronous excitation fluorescence spectra are collected. A computerized comparison of the resultant plots is conducted to determine if any differences occur between the plots. The results of these analyses suggest that this technique has great potential as an analytical tool, allowing the analyst to determine whether or not two petrolatum-based products could have a common source.