When you swallow a pill, how do you know whether your medicine is real or counterfeit? It’s a tricky question, but Yorkshire engineers have developed a method to print a unique identifier directly on to the tablet to allow fakes to be easily spotted.

Counterfeit medicine is a major problem worldwide. The World Health Organisation estimates that 10% of medicines in the world may be counterfeit and as many as 62% of pills bought online are fake or substandard.

Most anti-counterfeit devices are stuck onto the product’s packaging, making them easy to copy. The new technology, developed by Sofmat Ltd, in collaboration with engineers from the University of Bradford, uses tiny pins to imprint a unique barcode directly on to every pill, like a miniaturised Braille message. 

Speaking at the British Science Festival in Bradford, Sofmat director Dr Phil Harrison said “For the first time the same technology can be used on bulk packaging and on the actual product, making it much harder to create and ship fake products.”

The numbers on the pill and the packaging can then be compared. If the numbers differ, then the medicine is likely to be counterfeit.

The barcode is too small to see with the naked eye, but when magnified it looks like a QR code consisting of an array of six tiny holes created using six microscopic pins. The pins can be set to different lengths, allowing holes to be created with different depths. Each step in the length of the pin corresponds to either a letter (A-Z) or a number (0-9).

The system allows very small displacements to be made in each pin.  Each step is just 0.0004 mm, hundredth of the width of a human hair. Because the pins can be set to a range of heights, many more configurations are possible than when using a two-dimensional barcode or QR code.

Dr Ben Whiteside of the University of Bradford explains “A standard 2D barcode has two values, black and white.  We’re expanding that into shades of grey.”

With current technology, the company can produce 1.7 million number combinations, but they predict that they can increase this up to 30 billion variations.

And because the code is imprinted directly into the pill when the pill is made no extra ingredients are required, meaning that the technique does not require safety tests or approval from any regulatory bodies.

The barcode on each pill can be scanned using lasers. Sofmat Ltd say that the scanning equipment is small and portable, costs about £200, and could be distributed to doctors to check medicine at the bedside right before the patient swallows the pill.