Developing Methods to Improve the Quality and Efficiency of Latent Fingermark Development by Superglue Fuming


Mark D. Dadmun, Ph.D.

ABSTRACT:

The completed research program was designed to provide fundamental information that can be used to improve the superglue fuming method of developing latent fingermarks, by optimizing the acquisition of developed latent fingermarks and enhancing the quality of aged fingermarks. This has been realized by, first, using our expertise in polymer chemistry to explain the role of temperature on the superglue fuming of aged fingermarks and developing protocols to implement temperature control in a forensic laboratory. Our results show that fuming at lower temperatures improves the rate of polymerization that occurs during superglue fuming and thus, provides an easy and cost-effective method to improve the quality of aged prints developed by superglue fuming. More precisely the results of this project indicate that the optimum temperature of fuming is between 10 and 15 °C. Furthermore, any protocols that are devised to control the temperature of fuming must take into account the presence of the warm superglue fumes. The decrease in temperature also appears to improve the quality of aged latent prints.

Previous results also suggest that rehydration of an aged fingermark is critical to its successful development by superglue fuming, and thus we have investigated aggressive rehydration methods of aged latent fingermarks as a method to improve the quality of aged prints. Unfortunately, simply rehydrating fresh or aged prints by exposure to room temperature or boiling water vapor is not a sufficient method for improving print quality. In fact, exposure to boiling water vapor harms prints, presumably by removing initiators by dissolving them into the steam and releasing them from the print before fuming. Finally, we have completed Fourier Transform Infrared spectroscopy (FT-IR) experiments to monitor the molecular level changes during the polymerization of ethyl cyanoacrylate and the hardening process that occurs after polymerization, to provide guidelines that can be used to improve the turn-around time of obtaining a print that can be recorded and compared to a database. Thus, we have completed a series of experiments that provide fundamental information that forensic scientists in the field can use to create protocols to improve the effectiveness and optimize the process of the superglue fuming method to develop, visualize and analyze latent fingermarks.


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Article posted May 6, 2015

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