Symmetry and Scale: The Precise Engineering of Chitosan-Based Polyhedral for the Delivery of Therapeutic Materials at the Nanoscale

Preparation of chitosan-based drug delivery carriers requires converting linear polysaccharide chains into individual 3D objects. By building on the natural structural properties of chitin-based polymers, in addition to control the geometry of organically derived raw material from feedstock to submicron polyhedral or spherical dimensions. This geometric change is governed by a surface area-to-volume ratio that maximizes the exposure of the therapeutic payload to the external environment. The approach centres on the development of such carriers using ion-complexation and emulsification methodologies, which involve electrostatic cross-linking of ion-binding pairs to define an impenetrable boundary separating a liquid from a solid phase. Critical geometric factors, namely particle radius (size) and internal fill (loading efficiency), were optimized. A relatively low porosity was introduced by tuning the crosslinking density, which dictates the flow rate of the enclosing agents from the central region towards the periphery. The resulting configurations exhibit a degree of ordering in their packing and distribution, which is suitable for the spatial positioning of active agents within the defined geometric framework with accuracy. Targeted delivery depends on the direction and homing of nanoparticles towards specific biological targets. Using a sustained-release curve, the system maximizes bioavailability-density at the target site while minimizing volumetric dispersion in regions other than the systemic circulation.