Small particle reagents: Development of fluorescent variants

Small particle reagent (SPR) is a widely used method to develop latent fingerprints on non-porous and wet surfaces. Conventionally, molybdenum disulfide based SPR has been used for the development of latent fingerprints while some SPR based on other materials such as charcoal powder, zinc carbonate and titanium dioxide have been reported. Fluorescent preparations of molybdenum disulfide based SPR have also been reported. In the present work, a number of SPR based on zinc carbonate have been developed in combination with various fluorescent dyes to develop latent fingerprints on a number of non-porous surfaces. The quality of the developed fingerprints have been evaluated and found to be reproducible. The shelf life of the reagents developed is found to be acceptable for case work purposes. The relationship between the immersion period of the substrate bearing the latent fingerprints and reagent has also been examined.