Development and validation of an analytical method by HPLC-DAD for determination of caffeine in products based on guarana extracts (Paullinia cupana). Braz. J. Pharm. Sci. [Internet]. 15º de maio de 2023 [citado 17º de julho de 2024];59:https://doi.org/10.1590/s2175-97902023e22106. Disponível em: https://revistas.usp.br/bjps/article/view/212197