Encrypted Oligonucleotide Arrays for Molecular Authentication.

Counterfeiting is an incredibly widespread problem, with some estimates placing its economic impact above 2% of worldwide GDP. The scale of the issue suggests that current preventive measures are either technologically insufficient or too impractical and costly to be widely adopted. High-density arrays of biomolecules are explored here as security devices that can be coupled to a valuable commodity as proof of its authenticity. Light-directed DNA array fabrication technology is used to synthesize arrays that are designed to resist analysis with sequencing-by-hybridization approaches. A relatively simple sequence design strategy forces a counterfeiter to undertake a prohibitively high number of complex experiments to decipher the array sequences employed.