ETD

• drug delivery system

The prevalence of nasal and sinonasal disorders continues to increase, creating a growing need for effective local therapeutic interventions. This thesis work investigates the design, fabrication, and characterization of lyophilized poly(vinyl alcohol) (PVA) based sponges engineered as controlled sinonasal drug‑delivery systems. The work addresses limitations of current nasal packing materials — particularly inadequate swelling, poor drug‑release control, suboptimal mechanical performance, and patient discomfort — by developing a hydrogel polymer blend system whose structural and functional properties can be tuned through cross‑linking strategies. Lyophilization of emulsified polymer solutions was employed to generate highly porous scaffolds with interconnected channels, stable structures, and optimum drug release profiles.
The resulting sponges were evaluated through key performance metrics relevant to sinonasal applications, including initial and equilibrium swelling, pore size distribution, gel fraction, solubility, drug‑loading capacity, and release kinetics. Formulation development focused on PVA-based blends incorporating gelatin (G), carboxymethyl cellulose (CMC), and mechanical cellulose nanofibers (MCNF), while systematically investigating the influence of cross-link density achieved through physical methods such as freeze-thaw cycling and chemical cross-linkers including citric acid (CA) and glutaraldehyde (GTA).
This work investigates relationships between composition, processing conditions, and material performance in PVA-based composite sponges, providing insight into their suitability for sinonasal drug-delivery applications. The outcomes are expected to inform the development of customizable hydrogel-based nasal packing materials with the potential to enhance therapeutic effectiveness and patient comfort.