THIRUVANANTHAPURAM: Forensic investigators could soon detect hidden fingerprints that are difficult to spot on certain surfaces, thanks to a novel method developed by University of Kerala researchers to prepare a light-emitting nanomaterial.
The patented process uses a rare-earth-based compound that glows red when exposed to ultraviolet (UV) light, making faint fingerprint impressions easier to spot and examine. The material absorbs UV light and emits red light in the visible spectrum. This helps reveal faint fingerprint impressions that might otherwise go unnoticed.
“The nanophosphor is applied to the surface containing a suspected latent fingerprint. The deposited material interacts with the fingerprint residue,” explained Dr Sam Solomon of the department of optoelectronics, who led the research along with research scholar Divya Vijayan.
“Under UV excitation, the compound produces characteristic red emission. This emission enhances the visibility of the fingerprint pattern, facilitating its examination,” Sam added. Divya said two features make the material suitable for fingerprint detection. Its excitation wavelength matches that of commercially available UV lamps, while its nanoscale particles can adhere more readily to the fine features of fingerprints.
“Fingerprint details are very fine. The material needs to adhere to them. When it is a nanomaterial, it adheres more readily,” she said. The patent is specifically for method of preparing the compound, rather than the compound itself. Divya said the synthesis technique is not particularly expensive and is an efficient way of producing nanomaterials.
The research involved investigating different compositions and optimising the preparation conditions before arriving at the final formulation. The development process included systematic studies of the material’s structural, morphological and photoluminescent properties, followed by experiments to demonstrate its potential for latent fingerprint visualisation.
The entire research and development process took approximately six months of dedicated work. The next step is to explore commercialisation and have the material independently tested by forensic science laboratories. If its efficacy is established, it could potentially be considered for use in criminal investigations.
Divya said this was the second patent jointly obtained by her and Sam. Their other patent is related to LED technology, developed using a different compound.
How it Works
Rare-earth-based compound prepared using patented method
Nanophosphor interacts with suspected fingerprint residue on surfaces
Ultraviolet light triggers characteristic red light emission
Nanoscale particles adhere to fine fingerprint features
Red emission makes faint fingerprint patterns easier to examine