Turning okra into action: Sustainable nicotine transdermal plaster gels from plant-based polymers

Natural polymers are gaining momentum as sustainable alternatives to synthetic materials in pharmaceutical formulations. In this study, we developed a nicotine-loaded transdermal plaster gel using plant-based mucilage extracted from Abelmoschus esculentus (okra), blended with carrageenan and polyvinyl alcohol (PVA), and plasticized with glycerin. This eco-conscious formulation aims to reduce reliance on petrochemical-derived polymers while offering practical transdermal drug delivery potential. The okra mucilage yielded 2.28 ± 0.73 % of extractable powder and exhibited favorable physicochemical properties for film formation. When incorporated into the gel, variations in carrageenan and PVA content influenced color, viscosity, pH, and drying time. Films formed from these gels showed different mechanical strengths, with optimal flexibility and tensile performance achieved at a 7 % w/w mucilage level blended with both carrageenan and PVA. Thermal analysis confirmed good miscibility and thermal stability of the polymer blend, with decomposition temperatures exceeding 300 °C. In vitro studies demonstrated that nicotine release followed a first-order kinetic model, governed by formulation viscosity. Permeation through newborn pig skin followed zero-order kinetics, with steady-state flux and permeability coefficients indicating controlled delivery potential. This work demonstrates how okra-derived mucilage, a low-cost, biodegradable, and widely available natural polymer, can be harnessed for climate-conscious pharmaceutical development. The results support its use in sustainable transdermal drug delivery systems, offering a greener path forward in formulation science.