Formulation Development, Physicochemical Characterization, and In Vitro Evaluation of A Silver Nanoparticle-Loaded Phytoconstituent-Based Nanogel System for Enhanced Topical Drug Delivery

The present study aimed to develop and evaluate a novel silver nanoparticle (AgNP)-loaded nanogel formulated using the ethanolic leaf extract of Lantana camara for topical application. Phytochemical screening confirmed the presence of bioactive constituents such as flavonoids, tannins, and terpenoids, supporting its therapeutic potential and role in green nanoparticle synthesis. AgNPs were synthesized via an eco-friendly method and characterized using UV–Visible spectroscopy, FTIR, SEM, and TEM, confirming successful formation of spherical nanoparticles with desirable properties. The synthesized AgNPs were incorporated into Carbopol-based nanogel formulations (F1–F5) and evaluated for physicochemical characteristics, drug content, in vitro release, and antibacterial activity. Among the batches, formulation F3 demonstrated optimal performance with suitable pH (6.1), viscosity (8600 cps), high drug content (98.5%), and sustained drug release (87.6% over 8 hours). It also exhibited the highest antibacterial activity with a 21.5 mm zone of inhibition. The findings indicate that the developed AgNP-loaded nanogel, particularly formulation F3, represents a promising topical delivery system with enhanced antimicrobial and controlled release properties.