Edible optical tags make a stand against counterfeit drugs

Marie Freebody, marie.freebody@photonics.com

The global pharmaceutical market is worth $800 billion annually, and approximately 10 percent of this is thought to be counterfeit. Most drug manufacturers employ printed codes or serial numbers, bar codes or hologram stickers on packaging to authenticate their products. But a new optically read microtag that can be applied directly to the surface of the tablet or capsule could provide a more robust solution to combat counterfeiters.

TruTag Technologies has developed an edible microtag that reflects a unique spectral light signature that can be measured using a simple, low-cost spectrometer-based optical reader. This means that tablets can be verified through clear packaging without having to be removed from their blister packs.

Tablets with TruTags can be verified through blister packs using a portable spectrometer.

“On-dose authentication is a relatively new and emerging market that has been developing quietly in the background,” said Mike O’Neill, chief technology officer at TruTag Technologies. “There clearly is an industry need for on-dose authentication because the counterfeiters have figured out how to beat current packaging-level security systems.”

The technology, although extremely well suited to the pharmaceutical and supplements industry, also is scalable to applications in a wide variety of markets, including semiconductors, consumer electronics, aircraft parts, medical devices, food and wine, textiles and luxury goods.

The microtags contain tiny nanopores, or voids, manufactured to produce the tag’s unique spectral signature. The nano-porous structure can be controlled to affect the localized index of refraction, such that, in effect, the tablets are coated with custom-made optical interference filters. The company has controlled the manufacturing process so that up to a trillion unique spectral patterns can be achieved, allowing for an enormous amount of data management flexibility for customers.

Because the tags are made from clear, 100 percent silicon dioxide, which has been safely used as an ingredient in food and drugs for decades, they are both edible and biologically inert. The spectral code is etched into a silicon wafer from which microtags are created, and it is converted to silicon dioxide by heat. The resultant microtags, called TruTags, can be associated with information such as product strength, lot number, expiration date, authorized country of sale and authorized customer.

Hundreds of TruTags occupy an area about the size of the head of a pin. Each tag is barely visible to the naked eye. Images courtesy of TruTag Technologies.

For advanced security, the microtag characteristics can be linked to – and verified by – other information printed on the package, in such a way that the medicine and packaging are authenticated together.

“Tampering with either the package or the contents in this scenario would flag a security violation. The microtags can also be used to track placebos versus active dosages in clinical trial programs to ensure data integrity and speed time to market,” O’Neill said.

With tablet and capsule manufacturers in mind, the tags are applied via industry-standard pan coaters so that they can be applied to the surface of tablets or mixed into capsule shells during manufacture. The hope is that drugmakers will employ microtags for quality assurance, returns monitoring and in cases where counterfeit product is of concern.

TruTag Technologies currently is in trials with a major US nutraceutical company and has tested the microtags in a variety of applications both with clear and nominally opaque coatings.

O’Neill said that this pilot partner applied the tags to its tablets without making any changes to its existing manufacturing process and without any effect on the look or feel of the coatings. “We are now in four-corner testing to see how the tagged tablets perform under accelerated shelf life conditions, by applying high heat and humidity,” he added.