Electrochemical Determination of Caffeine in Tea Using a Polydopamine-Gold Nanocomposite

A polydopamine-gold nanocomposite (PDA/AuNPs)-based caffeine sensor with high sensitivity was fabricated. The electrochemical performance of the caffeine sensor was characterized in various electrolyte solutions, including sodium perchlorate, phosphate buffer saline, and choline chloride containing oxalic acid. The influence of interference agents, normally present in caffeine-containing samples, on caffeine detection was also studied. The PDA/AuNPs/GCE-based sensor showed excellent performance in the determination of caffeine in tea samples.