Stimuli-responsive nanogels for drug delivery and dental applications

This dissertation presents a systematic study on controllably degradable and stimuli-responsive nanogels for drug delivery and oral disease treatment. Initially, various nanogel synthesis strategies and characterization techniques were reviewed, outlining the scope of nanogels and their biomedical applications. Cyclodextrin-based nanogels were then synthesized via a surfactant-free approach and loaded with the antibacterial agent metronidazole. Their therapeutic potential was evaluated through antibacterial assays and relevant indicators in a rat periodontitis model. Subsequently, nanogels crosslinked with amide or ester bonds were designed to achieve tunable hydrolysis sensitivity. Coumarin-6 was encapsulated as a hydrophobic model drug to investigate how cross-linking chemistry and endogenous stimuli influence its intracellular stability and drug release profile. In addition, light-responsive photoacid nanogels were developed, and the effects of visible light irradiation on physicochemical properties were characterized. Cellular uptake efficiency was assessed in human gingival fibroblasts to elucidate structure-property-function relationships. Through synergistic design of material functionalization and crosslinking chemistry, the nanogel systems demonstrated precise control over degradability, release kinetics, and targeting capability. This work proposes a versatile, degradable, and stimuli responsive nanogel platform with significant potential for targeted therapy of oral diseases and other biomedical conditions.