Facile Synthesis of Nano Polydopamine Cellulose Hydrogel Beads for Sustained Release of Ciprofloxacin

Abstract Hydrogels are widely used as biomaterials in the biomedical field, particularly as tissue scaffolds and drug delivery systems. In this study, we report the synthesis of a novel drug delivery system based on a nano polydopamine–cellulose hydrogel. Microcrystalline cellulose was first dissolved in a NaOH/urea medium prior to physical crosslinking in different acidic environments, including hydrochloric acid and citric acid. Nano polydopamine and nano polydopamine glutaraldehyde were incorporated as functional polymers. The chemical structure, thermal properties, and surface morphologies of the resulting cellulose hydrogel beads were thoroughly characterized. The drug release properties of the hydrogels, including water content, drug loading capacity, and in vitro drug release profiles, were evaluated. All cellulose hydrogel beads retained substantial amounts of water and were capable of adsorbing and releasing ciprofloxacin in response to pH, while maintaining antimicrobial activity comparable to that of unmodified ciprofloxacin. Furthermore, the integration of PDA into the hydrogel significantly enhanced drug loading capacity and antioxidant activity. These findings highlight the potential application of nano polydopamine–cellulose hydrogels as controllable drug delivery systems for ciprofloxacin.