Vaseline treatment combined with a natural dye extract to enhance lip print contrast images

Abstract

Fingerprinting and DNA comparisons are the most commonly used methods in criminal investigations. However, lip prints can also be used as a supplementary tool because of the uniqueness of morphological patterns. A lip print not only can be used for personal screening by its pattern, it also carries genetic information that enables personal identification. Nowadays, there are various kinds of plants that are used for biological and histological staining due to an increasing market value associated with their application and sustainability. This study assessed the ability of natural dye extract to develop latent lip print contrast images and to preserve DNA for short tandem repeat analysis. Results revealed that roselle extract showed potential for the development of vaseline‐treated lip print contrast images on bond paper. Moreover, when roselle extract‐stained paper was compared with unstained paper, short tandem repeat profiles were not affected. Therefore, such dyes could be utilised for the development of latent lip print contrast images and their application could be extensively used to establish a personal identification database for reference in criminal investigations.