A range of chemical techniques were utilised for the enhancement of footwear impressions deposited on a variety of fabric types of different colours with urine as a contaminant. A semi-automated stamping device was used to deliver test impressions at a set force to minimise the variability between impressions; multiple impressions were produced and enhanced by each reagent to determine the repeatability of the enhancement. Urine samples from different donors were analysed using a spectrofluorophotometer revealing differences between individuals. Results indicated that the enhancement of footwear impressions in urine was possible using amino acid staining techniques whereas protein stains failed to achieve successful enhancement.
Farrugia, K. J., Bandey, H., Bleay, S., & NicDaéid, N. (2012). Chemical enhancement of footwear impressions in urine on fabric. Forensic Science International, 214(1), 67-81. https://doi.org/10.1016/j.forsciint.2011.07.020