Assembly of Uniform Functional Microparticles for Encapsulation and Controlled Release Via Spray Drying

W. Liu, C. Selomulya, Z. Wu, K. Waldron, W.D. Wu, X.D. Chen
Monash University, AU

Keywords: spray drying, uniform microparticles, controlled release

Summary:

Microparticles for encapsulation and controlled release have wide applications in functional foods and pharmaceuticals industries. Spray drying is a typical method to produce such particles on a practical scale, although conventional spray-dried products often show a wide range of particle properties. For the purpose of controlled drug delivery, the ability to design specific microstructural particles with (ideally) uniform properties is beneficial to realize the optimal therapeutic performance. At Monash University, we have developed a robust assembly approach for functional particles with targeted characteristics and sizes in a scalable, almost waste-free process, utilising a microfluidic spray-drying device (the only facility of its kind in Australia). The synthesis route is capable of effectively producing different types of functional particles with monodisperse size and uniform morphology. This work presents a series of studies from our group on the impact of formulation and spray drying conditions on physicochemical properties and functionalities of spray-dried microparticles. Examples in designing microparticles with distinct microstructures (core-shell, hierarchical, mesoporous, nanostructured composites) are presented. The uniform nature of particles produced allowed direct observation on the influence of microstructures and other properties of the matrix materials on controlled release kinetics, including for pH-responsive particles.