Brazilian scientists unveil breakthrough fingerprint powder for forensics
A research team from the Federal University of Alagoas in Brazil, led by Dr. Laís F. A. M. Oliveira has developed a new fingerprint powder that enables the detection of both new and old fingerprints of excellent quality on various surfaces.
Fingerprint analysis began to be widely used in forensic science at the turn of the 19th and 20th centuries and was implemented on a large scale in the 1940s. This technique is based on comparing fingerprint patterns, unique to each individual and unchangeable throughout their life.
Fingerprints remain on touched objects due to a layer of sweat and oily substances covering the fingertip. Fingerprint powder adheres to these substances, making the prints visible. The fingerprint images are compared with a database, allowing for the identification of individuals who touched specific objects.
The methods used so far did not always produce accurate results, because the image resolution depended, among other things, on the surface, fingerprint collection technique, and the properties of the fingerprint powder. Hence, Dr. Oliveira's team decided to develop a substance that provides high-quality images even with indistinct fingerprints. The research was published in the journal "The Royal Society of Chemistry Advances".
A revolution in forensic science
The powder was created from MCM-41 (microporous silica nanoparticles), chitosan (a polysaccharide from crustacean shells), and dansylglycine (a fluorescent organic dye). Tests have shown that the substance works on surfaces such as plastic, glass, metal, and paper, including banknotes, with various security features.
The new powder allows for the detection of both fresh prints and those over 30 days old, which is a challenge for currently used agents. The substance reveals main fingerprint patterns (loops, whorls, arches) and minutiae (bifurcations, bridges, eyes, hooks).
The silica nanoparticles strengthen the bonds between the fluorescent dye and the fingerprints, causing the ridges to glow intensely green under UV and visible light. The powder meets the quality requirements of the British Home Office, making it suitable for use by law enforcement agencies.
This new method captures the finer details of a fingerprint, making it easier to identify individuals and is expected greatly to aid in forensic investigations – summarised Dr. Oliveira.
