‘Spectral barcodes’ can tag individual medicines

A US company has developed a silicon-based label technology that can be used to tag and identify counterfeit medicines but is also completely edible.

Hawaii-based Cellular Bioengineering Inc (CBI) has been awarded funding by the US Army to develop the technology – known as TruTag – for use in preventing counterfeiting of medicines.

CBI manufactures the tags using high-purity silica that is Generally Recognized as Safe (GRAS) by the US Food and Drug Administration.

GRAS status is used by the FDA to identify ingredients or additives that can be used safely in food products. The porous silica (silicon dioxide) used in CBI’s tags is already used in pharmaceutical coatings or to aid the flowability of powders and granulations.

CBI’s silica technology can be used to authenticate a wide variety of products but is of particular interest in pharmaceuticals as it can be used within the dosage form rather than on the package or blister, according to the company.

It relies on recording an optical signature – one of a trillion possibilities - on a piece of porous silica wafer that is added to a product during the manufacturing process in a number of ways. The tags can be added onto the surface of a tablet coating, for example, or mixed into a dosage form as a forensic marker. Linking that unique signature to a particular product provides a unique identifier.

Tags are scanned using a spectrometer-based optical reader which can pick up signatures on a tablet even through a blister pack, said CBI. The spectral code can then be verified against other cryptographic information printed on the package, picking up instances where counterfeit blisters have been added to genuine packaging, for example.

“Each tag can reference a label in a secure database, where additional information about the item can be stored as desired, such as a link to a future e-pedigree track and trace system,” according to the company.

Moreover, because silica carries the signature in cross section, it is retained even if the tag is broken into separate pieces.

“This makes porous silica microtags suitable for forensic applications, where the tag may be subjected to rough handling,” according to CBI. “As long as any piece of the tag can be recovered, the information is not lost.”

The company said it is collaborating with Silicon Kinetics of San Diego, California, and its porous silicon laboratories in Maui on the development of the technology.

CBI is a long-standing player in the advanced materials market, with a portfolio spanning decontamination products for chemical and radioactive clean-up, artificial corneas in pilot clinical trials, and biosensor chips for use in detecting biological threats.