Development of an electrochemical caffeine sensor for PAT application in the food and beverage industry

This work reports on the development of an electrochemical sensor for on-line caffeine detection using screen printed graphite electrodes. The effects of solution pH and pre-treatment procedures on electrode performance have been discussed, as well as the modification of the electrode surface for increased electrode sensitivity. Successful caffeine determination in soft drink samples is described. The results indicate the potential of electrochemical sensors to compare and compete with the current off-line methods of caffeine analysis, such as HPLC, allowing for both a reduction in time and cost of product quality analysis. The successful performance of the screen printed electrode, as well as its low cost and small dimensions, will allow for efficient integration into a multi-parameter device for on-line quality control analysis.