In a groundbreaking development, engineers from the University of Glasgow have unveiled a new type of electronic tag that promises to lessen the environmental toll of single-use RFID technologies. These innovative wireless sensors operate without microchips, utilizing inexpensive coils and a unique sensing material made from polydimethylsiloxane (PDMS) and carbon fibers.

The new tags can identify objects and measure temperature, absorbing electromagnetic signals from a hand-held reader. This technology could significantly cut down the retail sector’s reliance on RFID chips, which currently sees over 10 billion tags used annually, most of which are discarded after a single use.

These chip-free tags are not only cost-effective but also versatile. They can be read by portable devices costing less than £100, paving the way for future ‘smart packaging’ that could monitor pH and humidity levels. Such advancements could alert retailers when food is at risk of spoiling or harboring harmful bacteria.

The lightweight and flexible nature of these tags opens doors to applications in healthcare and smart clothing, where they could unobtrusively track vital signs. In lab tests, the sensors demonstrated the ability to detect temperature changes between 20°C and 110°C, with a quick response time to fluctuations. This capability is crucial for food safety and medical uses, where timely data is essential.

Dr. Mahmoud Wagih, a lecturer at the James Watt School of Engineering, emphasized the importance of these wireless sensing tags for monitoring temperature across supply chains. By removing the need for microchips, these tags could cut costs and electronic waste significantly compared to traditional RFID sensors.

Co-author Dr. Benjamin King noted that the materials used are cheap and widely available, and the manufacturing process is simple and scalable. This accessibility could lead to widespread adoption of the technology, helping to mitigate the environmental damage caused by single-use RFID tags.

The research, titled ‘Large-Area Conductor-Loaded PDMS Flexible Composites for Wireless and Chipless Electromagnetic Multiplexed Temperature Sensors,’ is published in the journal Advanced Science. It received support from the UK Engineering and Physical Sciences Research Council (EPSRC) and the Royal Society. The future looks bright for these chip-free sensors, as they stand to revolutionize how industries approach sustainability and waste reduction.