ETD

• alginate
• ascorbic acid
• bioprinting
• dexamethasone
• electrospray
• mesenchymal stem cells
• PLGA

Ossicular chain reconstruction or replacement remains a clinical challenge, as general prosthetic approaches may be limited by extrusion, poor integration, and limited adaptation to patient-specific defects. Bioprinting offers a promising alternative for customized ossicular devices, while mesenchymal stem cells and encapsulated bioactive components may support osteogenic response and biological integration. This thesis presents a proof-of-concept approach based on osteogenic bioinks and controlled delivery systems.

Dexamethasone-loaded PLGA particles were produced by electrospray using different polymer concentrations, drug contents, and voltages, and characterized by SEM and image analysis. Electrospray conditions influenced particle formation, with voltage and PLGA concentration affecting size, distribution, and yield. Ascorbic acid encapsulation was studied using alginate-based formulations under different concentrations, flow rates, and voltages, producing micrometric particles, unlike submicron PLGA particles.

In parallel, cellulose, gelatin, alginate, and hydroxyapatite-based bioinks were used to bioprint cell-laden scaffolds with SAOS-2 or mesenchymal stem cells. Calcein Green and Alamar Blue assays showed that hydroxyapatite influenced cellular response depending on cell type and culture condition. Overall, this work explores a basis for integrating particle delivery systems and printable hydroxyapatite-containing bioinks in bioprinted ossicular devices.