Device for Electrochemical Caffeine Analysis in Fluids (DECAF): A Stir-Bar-Embedded Sensor for Real-Time Caffeine...

Area of Science:

• Analytical Chemistry
• Electrochemistry
• Sensor Technology

Background:

• Caffeine is the world's most consumed psychoactive substance.
• Accurate caffeine content labeling in beverages is currently unregulated.
• Unintentional caffeine overconsumption poses health risks.

Purpose of the Study:

• To develop a portable electrochemical sensor for real-time caffeine quantification.
• To address the lack of regulation in commercial beverage caffeine labeling.
• To minimize risks associated with unintentional caffeine overconsumption.

Main Methods:

• Development of the Device for Electrochemical Caffeine Analysis in Fluids (DECAF) using Nafion-modified laser-induced graphene (LIG) electrodes and a phosphate-buffered glass fiber (PBS-GF) layer.
• Utilized square wave voltammetry (SWV) for caffeine detection.
• Integrated wireless smartphone connectivity for data visualization and storage.

Main Results:

• Achieved a low detection limit of 0.06 mM and a linear detection range of 0.5–5.0 mM.
• Demonstrated high selectivity across varying pH and temperature conditions.
• Provided rapid, on-site analysis with results available within 5 minutes using only 200 µL of sample.

Conclusions:

• The DECAF sensor offers a compact, low-cost, and user-friendly platform for on-site caffeine monitoring.
• The technology has potential for extension to biofluid analysis and the detection of other analytes.
• This scalable solution supports personal health tracking and dietary management.