ANIK EKO NOVITASARI; NIKMATUL FITRIYAH. Effect of Extraction and Centrifugation on Caffeine Levels in Urine of Robusta Coffee Drinkers Using the Method of Uv-Vis Spectrophotometry. International Journal of Health, Economics, and Social Sciences (IJHESS), [S. l.], v. 7, n. 1, p. 219~225, 2025. DOI: 10.56338/ijhess.v7i1.6844. Disponível em: https://jurnal.unismuhpalu.ac.id/index.php/IJHESS/article/view/6844. Acesso em: 25 sep. 2026.