2020. Preparation and Characterization of Betel Leaves (Piper betle Linn) Extract Nanoparticle with Ionic Gelation Method. Journal of Tropical Pharmacy and Chemistry . 5, 1 (Jun. 2020), 15–20. DOI:https://doi.org/10.30872/j.trop.pharm.chem.v5i1.98.