Caffeine 'traffic light': Do you want to know how much caffeine is in your drink?

A team of researchers led by Young-Tae Chang from National University of Singapore and Yoon-Kyoung Cho from Ulsan National Institute of Science and Technology (UNIST), Korea, developed a fluorescent caffeine detector and a detection kit that lights up like a traffic light when caffeine is present in various drinks and solutions.

Caffeine drinks are ubiquitous and it would be unimaginable for many of us to go a day without caffeine. But certainly one begins to worry about how much caffeine one consumes every day. Here is a convenient way to see how much caffeine is in your drink. The novel caffeine sensor, named Caffeine Orange can be used for handy visualization of the amount of caffeine in your coffee or energy drinks.

With the non-toxic caffeine detection kit using Caffeine Orange, naked-eye sensing for various caffeine concentrations is possible based on color changes upon irradiation with the detection kit, and emitting a light to your drink with a green laser pointer. Solutions with high caffeine concentrations turn red while solutions with moderate and low caffeine concentrations turn yellow and green, respectively when the drink is irradiated with a laser pointer.

The novel fluorescent caffeine detector, called Caffeine Orange was developed by the team led by Prof. Chang from National University of Singapore. To fully utilize traffic–light caffeine sensor, they need to extract caffeine from solutions. An automated system by incorporating microfluidics technique developed by the UNIST research team, lab-on-a disc, was applied to extract and to measure caffeine.

Beverages containing caffeine, such as coffee, tea, soft drinks, and energy drinks, enjoy great popularity around the world while various studies have raised both positive and negative health related concerns. But it is clear that caffeine overdose can lead to caffeine intoxication, with symptoms such as anxiety, irregular heartbeat, and insomnia. In extreme cases, a large overdose can lead to hallucinations, depression, or even death.