Determination of theobromine in cocoa products and tea samples: A new sensitive and selective electrochemical sensor approach using Printex L6/Au and polyaniline - Oliveira, Igor G.S; Gallina, Fernando C; Affonso, Muriel R.; Bimbi Junior, Fausto Eduardo; Souto, Robson S.; Lanza, Marcos Roberto de Vasconcelos; Martelli, Silvia Maria; Barros, Willyam Róger Padilha (Journal of Food Composition and Analysis, 2025)