In a joint project by IIT Kharagpur and NIT Durgapur, funded by the HRD Ministry and the Council for Scientific Research, the institutes have developed a technology to enhance latent fingerprinting to increase the efficiency of forensic detection, among other things.
The paper, jointly written by the two institutes, has been published in Nanoscale — a publication of the Royal Society of Chemistry, last week.
“Fingerprint detection is becoming more and more important these days. Apart from being vital in the forensic sciences and helping in solving crimes, latent fingerprinting (LPF) has become imperative in many areas like for Aadhaar cards, visas and also at airports. Our endeavor is to see how to get better latent fingerprints,” said Chandrashekhar Tiwari of the department of Metallurgical and Material Engineering at IIT Kharagpur.
Head of Physics department at NIT Durgapur, Pathik Kumbhakar, who is also the main supervisor of the project, said, “When we place our hand on a surface, a secretion from our fingers touches the surface which creates a fingerprint. But this doesn’t remain for long. In our study, we have used the nanostructure material that we have developed for up to two months and have found that the fingerprint stays longer. Also this material is luminescent under ultraviolet lights which is a huge advantage.”
“Security concepts, such as LPFs, encoding information for anti-counterfeiting, encryption of confidential data, etc., are now widely used in the forensic department. The topologically unchanged ridge pattern of the human finger produces a unique fingerprint. Not only does it differ from one individual to another, it also differs from one finger to another. During contact between a finger and a surface, the secretion present at the surface of the skin are transferred to the substrate which leaves an impression of the ridge pattern. Therefore, fingerprints represent the best reference for personal identification in forensic science due to their high stability, uniqueness and complexity of ridge patterns,” the paper stated.
“What we have done is used zinc sulphide, which is commonly used, and doped it (mixed in very small quantity) with copper and manganese. This as a material which picks up latent fingerprints has optimal visibility with a far more enhanced fingerprint,” said Tiwari. The mixture can be used as a powder, liquid solution, gel or paste. “The other advantage is that it can be applied to the fingertips and fingerprints can be lifted without the use of sophisticated expensive equipment, Tiwari added.