A US firm specialising in analytical tracers used in the animal feed industry has developed a variant of the technology aimed at pharmaceutical applications.
San Francisco-based Micro-Tracers has been producing its tracers - which consist of food-grade plastic embedded with iron particles coated in food dies - for more than 50 years. They are added alongside ingredients such as vitamins, minerals or premixes to allow their presence in animal feeds to be confirmed.
"Our microtracers are used in the animal feed industry widely around the world to protect patent and distribution rights, as well as to determine adequacy of mixing and cross-contamination control procedures," according to Dr. Nikolay Barashkov, director of R&D at Micro-Tracers.
While the company does not yet have any clients signed up in the human pharma sector, its tracers are used in veterinary drugs added to feed.
The new line of micro-engraved tracers - called Secur - was launched a couple of months ago and has arisen out of technology used in the semiconductor industry. The tracers can be used both on the packaging and label of pharmaceutical products as well as an ingestible taggant for solid oral dosage forms.
"Our tracers can be applied to the label, included inside of the pill, or in the coating- it all depends on the client’s preference," said Barashkov.
They take the form of magnetically-attractable particles - up to 100 microns in diameter with lettering 10-20 microns in height - and are considered to be Generally Recognised As Safe (GRAS) status FDA regulations.
They also comply with most elements of the US FDA guidance finalised in 2011 on physical-chemical identifiers (PCID), defined as a substance or combination of substances possessing a unique physical or chemical property that can be used to identify and authenticate a drug product or dosage.
For example, they don't include ingredients derived from food allergens, all the components are relatively inert and they don't contain any release-controlling excipients. The company does need to perform some additional studies on the behaviour of very small iron particles in simulated gastric and intestinal fluids, said the spokesperson.
Instant identification of the tracer is possible using an ultraviolet black light, as this will cause the embedded food dye to fluoresce, microscope, and thanks to their iron content they can be separated out using a magnet.
Each micro-engraved tracer could include a company name and/or other identifying information (i.e. lot number, production date, expiration information).
"Manufacturing these tracers requires extremely specialized semiconductor equipment and a variety of technical skills," according to Micro-Tracers.
"The difficulty and cost to acquire such equipment and the expertise necessary to operate it pose high barriers to entry for potential counterfeiters."
They are also more affordable than other anti-counterfeiting measures that may add as much as 10 per cent to the manufacturing costs of the drug, said the company. By contrast, micro-engraved tracers could be added at "a fraction of the cost", it suggests.