The focus of the project of ESR1 is to develop a bio-compatible particle formulation as a drug delivery system for biopharmaceuticals. To achieve this goal, the project will start with the synthesis and modification of biopolymers such as chitosan that will be then used as main components for the drug delivery system. Biopolymers have been chosen for their biocompatibility and for their mucoadhesive properties. The functionalisation of such polymers aims to improve the characteristics of the polymers, such as mucoadhesive properties, stability and controlled release ability. The functionalised polymers will therefore be characterised by physical-chemical methods to define their characteristics. The polymers with the better characteristics will be used for the formulation of spray dried particles. The particles will be obtained by physical crosslinking with a proper, biocompatible, crosslinker agent, based on the polymer characteristics. The particles will be characterised by investigating their size, shape and zeta potential, their encapsulation efficiency, swelling behaviour and their mucoadhesive properties. The result of the previous studies will be use to optimise the particle formulation and finely tune its characteristics to match the project goals.

Design of experiments (DoE) will be used as an aid to reach these goals and to better optimise all the parameters involved in the spray drying process, such as the temperature and pressure of the system, the flow rate and feed rate, the concentration of both the crosslinker and the polymer solution. Release studies will be then performed to investigate the release behaviour, together with stability studies in short and long term, to understand the stability of both the drug delivery system and the encapsulated biopharmaceuticals. These studies will be supported by in vitro studies in proper cell lines, representative of the olfactory mucosa, and subsequently by in vitro studies on porcine mucosa. The release kinetics of the biopharmaceutical from the drug delivery system will be defined, with the help of the knowledge obtained from the partners during secondments.