One ring to protect them all

Something from Tolkien? Or more likely a James Bond film—a ring that can detect external chemical or biological threats like explosives or nerve gas. In today’s political climate it could be a handy accessory.

A team of researchers from the University of California San Diego have been working to bring this idea out of Hollywood and into the real world.

Following the development of other wearable technology such as fitness trackers, heart rate monitors and blood-sugar sensors for diabetics, there’s now a wearable chemical sensor that can pick-up external, rather than internal, information about our environment.

The technology consists of two parts—an electrochemical sensor that uses two highly sensitive electrochemical techniques (square wave voltammetry and chronoamperometry) to detect potential biological and chemical threats and, beneath this, a tiny circuit board to process the data and send it wirelessly to your phone or computer. The on-board chip digitises signals from the sensor, then processes them to identify the combinations of current and voltage spikes that could only come from the target chemicals. The ability of the technology to process information and provide updates over Bluetooth has resulted in it being dubbed the ‘Lab-on-Ring’ by its creators.

The sensor is housed in a 3D printed ring casing, allowing it to be portable and easily worn.

According to Professor Paul Mulvaney, who works on portable sensor technologies with the Defence Science Technology Group, 'portable, real-time detection of air-borne toxins remains an important challenge and this exciting new platform could have applications in military, environmental and industrial settings.

During testing, the prototype was exposed to a range of organophosphate nerve agents (the same family of chemicals as Sarin and VX gas) and explosive precursors (for example, the chemicals used to make TNT or peroxide-based improvised explosive devices) in both liquid and vapour form.

Despite its small size, the sensor proved to be sensitive and selective enough to detect a large number of chemical threats. The team hope that with further research, it will be possible to identify additional hazards—including mixtures of different compounds, and to increase the longevity of the sensor. At present it is only functional for two hours at a time.

The device could be used by people working in security or other high-risk areas, though as its functionality expands the range of situations in which the ring could be used is expected to grow.

And while most of us are lucky enough to not need to worry about being exposed to dangerous chemicals on a daily basis it’s good to know that if one day we are, science is working on a way to protect us.