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This thesis investigates the incorporation of the biopolymer pullulan (PUL), both in regular powder form and as elongated particles, in a capsular device in order to enhance drug delivery. The drug release of PUL powder in a matrix of ethyl cellulose and a plasticizer was compared to previous works with KIR particles. Bad dispersion as well as degradation ocurred during micro-injection molding of the PUL powder mixture, which hindered the desired enhanced drug release with respect to the one of KIR. Thermal analysis and extrusion with rheological measurements was executed to analyze the aforementioned problems and possible solutions are suggested. Next a rheological characterization was carried out on different concentrations of PUL water solutions in view of continuous fibre production via electrospinning, in particular examining the viscoelastic behaviour of the solutions. The solution with highest concentration and molecular weight proved to be most suitable for electrospinning. Indeed, uniform and defect free fibres were obtained from this solution. When making a large amount of fibres, their high surface to volume ratio disrupted the separation process because of too large adhesion of the fibres. Division of the fibre mats was ineffectively tried with an ultrasounds and ball milling. To avoid this difficult separation, creation of short fibres seemed to be a solution. For this reason sprayspinning was implemented, however solvent evaporation was not sufficient, as still a lot of water droplets were obtained. Use of an environmental controlled chamber is proposed as a solution. To cope with these issues, it was decided to mechanically reduce the electrospun fibre mats to small flake-like structures. Due to time reasons, it was not possible to test the effectiveness of these flakes of nanofibres and compare it to the powder form. This part would then be addressed to future works.