Candy-coating method to fend off pill counterfeiting

A scientist spent months covering pills in a unique pattern of hundreds and thousands — but, far from being a failed attempt at making fairy bread, the colourful covering on the pills could eventually be a method of protecting against pharmaceutical fraud.

The coating technique has been called CandyCode by its inventor, bioengineering Professor William Grover from the University of California, Riverside. It functions as a sort of edible barcode, with the pattern created by the different colours of hundreds and thousands — technically known as nonpareils — acting as a unique identifier. If a pharmaceutical producer covered each pill it produced in the tiny candies then uploaded a photo of it into its system, people would be able to guarantee that a pill is genuine by scanning their drugs using a smartphone app.

“The inspiration for this came from the little colourful chocolate candies,” Grover said, in reference to the chocolate sprinkle confectionery known as Freckles in Australia.

“Each candy has an average of 92 nonpareils attached randomly, and the nonpareils have eight different colours. I started wondering how many different patterns of coloured nonpareils were possible on these candies.

“It turns out that the odds of a randomly generated candy pattern ever repeating itself are basically zero, so each of these candies is unique and will never be duplicated by chance.”

Grover glued hundreds and thousands to the pills using cake decorating glue and then had an algorithm assess how unique the pills were and how many variations would be possible, to see how much of an impact the system could have.

“Using a computer simulation of even larger CandyCode libraries, I found that a company could produce 10¹⁷ CandyCoded pills — enough for 41 million pills for each person on earth — and still be able to uniquely identify each CandyCoded pill,” he said.

The technique can be applied to other mediums such as bottle caps or garment tags, for fraud protection of wine, perfume or high-end clothing.

Unfortunately, having bright colourful pills is of course a safety hazard for children; however, the researcher does note that other potentially less eye-catching methods using the same principles could be used instead.

The paper describing the method was published in Scientific Reports.

Image credit: William Grover/UCR