Presentation (CTI)

OBJECTIVES: To develop and optimize a transdermal under-eye patch combining Centella asiatica with niacinamide for dark circle reduction, and evaluate its physicochemical, release, antioxidant, anti-inflammatory, cytocompatibility, and ROS suppression activities.
METHODS: Six PVA-based formulations (F1-F6) were prepared using solvent casting. F6 (optimized) contained Centella asiatica 5g, niacinamide 1.5g, PVA 1g, and glycerol 0.5mL. Patches were characterized for thickness, folding endurance, moisture absorption, drug content, and pH. In vitro drug release was studied over 14 hours. Release kinetics were analyzed using zero-order, first-order, Higuchi, Korsmeyer-Peppas, and Hixson-Crowell models. Antioxidant activity was assessed via DPPH and nitric oxide scavenging. Anti-inflammatory activity via protein denaturation inhibition. Cytocompatibility and ROS suppression were assessed in NHDF cells. All data expressed as mean ± SD (n=3)
RESULTS: F6 showed thickness 0.19±0.01mm, folding endurance 175±7, pH 5.8±0.02, and drug content (Centella 82.5±0.12%; niacinamide 22.8±0.12%). F6 exhibited sustained release (57.07±0.11% at 14h) following Korsmeyer-Peppas model (R²=0.992). F6 demonstrated DPPH scavenging 85.4±0.4% and NO scavenging 91.4±0.4% (p<0.001). Anti-inflammatory activity showed protein denaturation inhibition 84.7±0.4% (p<0.001). NHDF cells showed 89.7±0.4% viability at 100% extract with 55% ROS reduction, superior to Centella alone (78.6±0.4%; 45% ROS reduction)
CONCLUSIONS: The optimized Centella asiatica-niacinamide transdermal patch (F6) demonstrated favorable physicochemical characteristics, sustained diffusion-based release, and synergistic antioxidant, anti-inflammatory, and cytoprotective effects. This novel patch offers a non-invasive, residue-free, sustained-release alternative for under-eye dark circle reduction with potential for improved adherence.