Determination of Caffeine Content in Ethanolic Extract of Robusta Coffee Beans (Coffea canephora) Using UV-Vis Spectrophotometry. JRKI [Internet]. 2026 May 30 [cited 2026 Oct. 7];8(2):182-8. Available from: https://jurnalfarmasi.or.id/index.php/jrki/article/view/936