Broad Scale & Structure Fabrication of Healthcare Materials for Drug and Emerging Therapies Via Electrohydrodynamic Techniques

The engineering of advanced healthcare materials provides a platform to address challenges facing interdisciplinary scientists, clinicians, pharmacists, biomaterial scientists and biomedical engineers. Niche and timely developments arising from the synthesis or extraction of more biocompatible materials, new biologically active components, clearer insights into disease mechanisms and novel therapies or strategies provide several timely opportunities. These include enhanced therapies with greater patient compliance, improved disease targeting, better diagnosis and bespoke medications for individuals. Electrohydrodynamic atomisation (EHDA) engineering comprises several processes making use of electric fields (e.g. through an applied voltage) interplaying with several forces (e.g. gravity and surface tension). Coupled to advanced materials (e.g. formulated media) and specifically configured apparatuses (e.g. nozzles, collectors and downstream processes); effective and controlled fabrication of various structures (fibers, particles, bubbles, grids, droplets) on various scales (macro, micro and nano) possessing various dimensions (2D, 3D and 4D) is readily achieved. The processes have distinct advantages compared to established engineering methods (ambient environment engineering, low shear, scalability, compartmentalisation etc.). This detailed review focuses on key concepts and developments in EHDA engineering pertaining to underlying principles, enabling tools and engineered structures specifically for healthcare remits. From initial experiments involving the behaviour of non-formulated liquids on charged amber to recent developments in complex 3D matrix printing; the EHDA route has progressed significantly, most rapidly in the last two decades, and is capable of providing timely platform opportunities to tackle several global healthcare challenges