Summary

The particulate interactions that occur in the manufacture and use of dry powder inhalers (DPIs) can be important factors in their efficiency and potential issues for drug delivery. The aim of this work is to produce 3D printed structures of well-defined morphology and surface chemistry on the micron scale to aid our understanding of particle-surface interactions. This has been achieved using a novel two-photon 3D printing technique. This work shows the production of semi-circular test geometries on the micron scale, which have been coated with model coatings (plasma polymerised hexane and acrylic acid) producing a consistent well-defined surface chemistry. Initial particle-substrate adhesion measurements was acquired using atomic force microscopy force-volume mapping and demonstrated and the differences observed using different surface chemistries and different AFM colloidal probes discussed. The work aims to isolate and investigate the effect of morphology and surface chemistry on particulate adhesion and assist in the development of better DPI formulations and devices.