Formulation, Physicochemical Characterization, and Antioxidant Activity of Moringa (Moringa oleifera Lam) Leaf Ethanol Extract Nanogel

Oxidative stress caused by free radicals triggers premature skin aging, creating a need for stable and effective natural topical antioxidant formulations. This study aimed to formulate a nanogel containing the ethanolic extract of moringa leaves (Moringa oleifera Lam) by testing concentrations of F1 (2.5%), F2 (5%), and F3 (7.5%) and to evaluate physical characteristics and antioxidant activity. The methodology began with the preparation of a nanogel base using Carbopol 940 and Tween 80, followed by physical quality testing (organoleptic properties, pH, spreadability, and particle size using a Particle Size Analyzer) and in vitro antioxidant activity testing via the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. Physical evaluation results showed that all nanogel formulas exhibited a semi-solid consistency, a characteristic herbal odor, and a dark green to deep green color; they possessed pH values ​​compatible with skin pH (4.93–5.45), good spreadability (5.40–6.75 cm), and particle sizes within the nano-scale range (101–180 nm). Antioxidant test results demonstrated that inhibitory activity increased with extract concentration (dose-dependent manner), with IC₅₀ values ​​of 112.774 µg/mL (moderate) for F1, 67.135 µg/mL (strong) for F2, 29.045 µg/mL (very strong) for F3, and 17.417 µg/mL for the pure extract. In conclusion, the Moringa oleifera leaf ethanolic extract nanogel meets the physical quality criteria for topical preparations and exhibits very strong antioxidant activity.