A material changes colour to indicate when medicines are too warm

A simple indicator label could save money and prevent waste in the pharmaceutical industry

Spotted: When distributing perishable products, maintaining a seamless cold chain is key. And with items like medications, not keeping them at the correct temperature can render them ineffective, and potentially harm the end user. While wireless sensors can monitor conditions, these devices can be expensive and are not always practical. Now, researchers in China and the US may have an alternative.

The researchers, based at the Shenzhen Institute of Advanced Technology and the University of California Riverside, recently published a paper reporting on a class of coloured microcrystals that become colourless over a wide range of temperatures.

The researchers created an indicator system using silicon dioxide nanoparticles, which appeared bright green or red in water, and liquids with variable melting points. By combining the two, the researchers produced a system that lost colour when a temperature increase occurs in a specific temperature range.

As a proof-of-concept, the researchers packaged the two-part indicator system into flexible vial labels containing a QR code. As the materials in the vial warmed up, the labels changed from coloured to colourless, clearly demonstrating that the system worked.

Securing the cold chain not only saves money and lives, but fewer losses also translates into improved sustainability. In fact, improving the cold chain is the focus of a number of recent innovations spotted by Springwise in the archive. These include solar-powered refrigerated containers for use in remote areas and a wireless system for tracking temperature and humidity during transport.

Written By: Lisa Magloff