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Abstract

Electrohydrodynamic techniques, particularly electrospinning and electrospraying, offer versatile routes for fabricating micro- and nano-structured materials with tunable architectures. In this thesis, these methods are explored as platform technologies for creating porous scaffolds tailored for biomedical and bioengineering applications. The overarching goal is to harness electrohydro- dynamic processing to porous functional scaffolds that enable actuation for soft robotics, exhibit conductive functionality and guide cell behaviour. The focus of this work is based on electrospinning-based sacrificial templating for scaffold fab- rication. Electrospun fibres were employed as removable templates to generate interconnected porous architectures in different material systems. A thermo-responsive poly (N-isopropyl acry- lamide) hydrogel scaffold was first developed, demonstrating reversible swelling and actuation, with potential applications in soft robotics. This approach was then extended to electroconduc- tive polypyrrole based hollow microtube scaffolds, where hollow microtube networks with tunable diameters were engineered. Electrical characterisation revealed Ohmic behaviour, with conduc- tivity strongly dependent on microtube diameter, highlighting the potential of these conductive scaffolds in neural tissue engineering, electroactuation, and bioelectronic interfaces. In the next step, porous poly (dimethylsiloxane) scaffolds were fabricated using the same templating strategy to create controlled microchannel networks. These scaffolds served as in vitro platforms to study cell migration under 3D confinement, mimicking the physical constraints encountered in native extracellular environments. This thesis also shines light on fundamental aspects involved in electrohydrodynamic process with an introduction to electrospraying technique and its versatility. Electrospraying was further adapted to encapsulate living cells within polymeric microcapsules, creating biocompatible carriers that preserve cell viability. These microcapsules system can open opportunities for studying con- fined cell migration, modelling metastasis, and developing therapeutic delivery systems. Together, the results presented in this work establish electrospinning and electrospraying as complementary, modular approaches for engineering porous scaffolds and microcapsules. By spanning applications from soft robotics and conductive scaffolds to cell migration platforms and encapsulation tech- nologies, this thesis demonstrates the versatility of electrohydrodynamic fabrication in addressing challenges at the interface of materials science, biology, and medicine.