Spectrophotometric Methods for the Determination of Caffeine in Beverages Use Solvent Extraction Techniques and Adsorption of Activated Carbon. Journal of Tropical Pharmacy and Chemistry , [S. l.], v. 5, n. 4, p. 338–346, 2021. DOI: 10.30872/j.trop.pharm.chem.v5i4.256. Disponível em: https://jtpc.ff.unmul.ac.id/index.php/jtpc/article/view/256. Acesso em: 13 dec. 2025.