Caffeine detection in green tea and coffee samples using nanoelectronic device based on bimetallic FeNi-metal organic framework

Caffeine is a stimulant of central nervous system that is normally found in a range of foods, drinks and medications including tea, coffee, chocolate, energy drinks, and syrups. The levels of caffeine play an important role on the impact of its effect on human health. Hence, in this work, we have developed a nanoelectronic device employing the bimetallic metal-organic frameworks (MOFs) for the rapid detection of caffeine. The fabricated probe has been characterized through various physical characterization techniques, including SEM, EDX, FTIR, XPS, and electrochemical techniques. The developed chip was able to detect caffeine in a linear dynamic range of 50 to 1 × 10⁻⁵ mM with a detection limit of 1.26 (±0.06) nM. The developed probe was also tested against various interferants and its practical applicability was evaluated using green tea and coffee samples as real matrices. Further, 3D-printed cascade model was used for the device development and the developed chip shows its promising advantage in monitoring caffeine in diverse beverages.