A research team led by Prof. Young-Tae Chang from National University of Singapore and Prof. Yoon-Kyoung Cho from Ulsan National Institute of Science and Technology (UNIST), Korea, published news of their invention in the journal Scientific Reports on July 23.
Noting worries about caffeine consumption levels, the researchers claim the new ‘Caffeine Orange’ kit provides a convenient way to see how much caffeine is in, say, a cup of coffee or an energy drink, via a handy three stage visualization method.
Danger of caffeine intoxication
“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,” the scientists write.
Traditional caffeine detection methods include thin-layer chromatography (TLC), liquid chromatography mass spectrometry and immunoassay, but these methods required expensive equipment and were not convenient for public use, the scientists explain.
The scientists' kit detects caffeine concentrations based on color changes in a drink, say coffee, upon irradiation, using a green laser pointer.
These colors are then measurable using a fluorescence standard curve.
If high caffeine concentrations are detected in solutions the lights turn red, while solutions with moderate levels turn yellow and low green.
To fully utilize the affeine sensor, the UNIST team extracted the alkaloid from solutions and measured levels using an automated system – Lab-On-A-Disk – incorporating their own microfluidics techniques.
Lab-On-A-Disk to automate detection
Prof. Chang said:"You can use this caffeine detection kit as a 'traffic-light caffeine amount designator'” to automate detection and help estimate caffeine amounts even faster.
He added: "The reddish orange color indicates a stop sign for people who cannot uptake caffeine, while yellow and green indicate a warning signal and safe zone respectively."
Chang et al. say that before they developed their 'traffic light designator' no practically applicable and customer-friendly detection methods have been reported.
They add that the automated new kit's advantages include (1) ease of construction and handling (2) safe and customer-friendly (3) very fast caffeine extraction (4) adapatability to chemically and physically 'complicated' beverages.
Title: 'Make Caffeine Visible: A Fluorescent Caffeine 'Traffic Light' Detector'
Authors: Xu, W., Tae-Hyeong, K., Zhai, D., Er, J.C., Zhang, L., Kale, A.A., Agrawalla, B.K., Cho., Y-K., Change, Y-T
Source: Scientific Reports, Published online July 23 2013, doi:10.1038/srep02255