- 期刊
A Bufferless Oil Red O Formulation for Developing Fingermarks on Wet Substrates
摘要
In crime scenes, relevant documents are sometimes torn or thrown into toilets or ditches to destroy evidence. At the scene of a fire, the environment becomes wet after firefighters extinguish the fire. Under these conditions, small particle reagent (SPR) can be successfully used to develop latent fingermarks on nonporous substrates. However, ninhydrin cannot be used to develop latent fingermarks on porous substrates under wet conditions because amino acids are soluble in water. To overcome this limitation, Oil Red O (ORO), a commonly used stain for detection of lipids in various biological fields, has been used to reveal the presence of residual water-insoluble components. Using bufferless ORO formulations, researchers have examined the effectiveness of sodium hydroxide, methanol, and different buffers. In the present study, we evaluated the effectiveness of a bufferless ORO technique for developing fingermarks on wet and special substrates, such as thermal paper and Bristol boards, in a wet environment in Taiwan. Bufferless ORO was used to develop latent fingermarks on glass, transparent plastic, thermal paper, A4 paper, and Bristol boards in a wet environment. Latent fingermarks successfully developed red ridges with a pink background on thermal paper and discolored the specimen. Bufferless ORO has been approved for use based on its environment-friendly features. Therefore, based on our analysis, the best way to develop latent fingermarks on regular wet paper was to use ninhydrin first, followed by ORO.