Abstract
Oral mucositis is a debilitating inflammatory condition requiring effective topical formulations with antimicrobial and wound healing properties. This study aimed to formulate and evaluate Gracilaria foliifera-mediated zinc oxide nanoparticles (ZnO-NPs) incorporated into a sodium alginate gel for potential oral mucosal applications. The formulated ZnO-NPs-infused gel was characterized using UV-visible spectroscopy, FT-IR, SEM, EDX, and X-ray diffraction. Physical stability was assessed based on appearance, pH, texture, and phase separation. Antioxidant, anti-inflammatory, antimicrobial, and antibiofilm activities were evaluated in vitro. Drug-release behavior and cytotoxicity were also investigated. UV-visible spectroscopy showed absorption peaks at 321 and 320 nm at 0 and 24 h, respectively, indicating good nanoparticle stability within the gel matrix. SEM revealed irregularly shaped ZnO-NPs with an average size of 166 nm. EDX confirmed Zn (41.48%), O (19.7%), and C (38.7%), while X-ray diffraction showed 64.9% crystallinity. The formulation exhibited 74.3% radical-scavenging activity at 100 µg/mL and 64.07% inhibition of albumin denaturation at 400 µg/mL. It demonstrated antimicrobial activity against Streptococcus mutans, Escherichia coli, and Candida albicans and reduced S. mutans biofilm formation. Approximately 50% of the loaded ZnO-NPs were released within 12 h, while cytotoxicity assessment indicated good in vitro biocompatibility at 5-75 µg/mL. The ZnO-NPs-infused sodium alginate gel exhibited antioxidant, anti-inflammatory, antimicrobial, and antibiofilm properties in vitro, supporting further investigation for oral mucosal applications. However, mucosal safety and therapeutic efficacy remain to be established through in vivo studies.