Seeing into the infrared: a novel IR fluorescent fingerprint powder.

A preliminary study demonstrates that latent fingermarks across a range of highly patterned, coloured non-porous and semi-porous substrates may be clearly developed and imaged in the near infrared following a simple dusting method using finely divided spirulina platensis powder, a naturally occurring, non-toxic algae, used widely within the food industry. Troublesome printed/multicoloured backgrounds show less interference with the fluorescence observed using this material, unlike conventional luminescent powders which fluoresce in the visible spectrum alongside the background to which they are applied. The material shows promise for use both in the field and in the laboratory.