Working with capsules of dye just a few billionths of a metre in diameter, researchers at University of Toronto and the advanced optical microscopy facility at Toronto's Princess Margaret Hospital have created a new strategy for encrypting photographs, signatures and fingerprints on security documents.
THE sweaty, greasy residue that forms a fingerprint might one day reveal the identity of a criminal as surely as the pattern of whorls and ridges.
Whenever we touch something, we leave behind a minute residue of proteins, salts and fatty acids. Because the exact proportions of these components vary between individuals, some forensic scientists suspect that a chemical fingerprint could be as unique as a physical one.
Imagine a material that could expand by three to six times in size while remaining strong and stiff, and also could be biodegradable and biocompatible. Such a material would be invaluable as a wound-healing bandage or possibly a drug-delivery mechanism.
Technologies of security activity
