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The electrohydrodynamic (EHD) technique has traditionally been confined to the bench-top. Recently, a portable EHD device was constructed that allows the process to be applied in a much more flexible and versatile manner. In this article, the effect of electrode and collector height on the fibers generated by EHD and wound-dressing forming capabilities of the device tested on different types of simulated wound morphologies were investigated. Dressings were also fabricated on living tissue to investigate jet behavior and product morphology. The EHD device was found to be capable of controlled deposition of micrometer-sized poly(D,L-lactide-co-glycolide) acid fibers that can form an opaque, waterproof wound dressing on human skin within a few minutes with excellent adherence.

Encapsulation of materials in fibres with a well-controlled size distribution is an important application of the electrospinning technique. This study investigates the effect of key parameters of the coaxial electrospinning process including flow rate, applied voltage and polymer concentration on the efficient encapsulation and size distribution of perfluorohexane (PFH) in polymethylsilsesquioxane (PMSQ) microfibres. Perfluorohexane can be exchanged for a drug via a simple diffusion-controlled process. By altering the polymer concentration and processing parameters, PMSQ microfibres with different diameters, PFH core size and core-to-core distance were obtained. It was found that PFH-encapsulated fibres with a diameter between 8 and 15 μm can be prepared when the PMSQ concentration is kept between 55–70 wt%. The PFH regions (cores) encapsulated in the fibre are uniformly distributed and of size 5–14 μm. The core-to-core distance significantly increased from 4 μm to 22 μm when the applied voltage was increased from 8 kV to 11 kV. These results indicate a potential strategy for controlling fibre diameter, core size and core-to-core distance by using coaxial electrospinning as the forming procedure and thus this work will help to advance biomedical engineering applications, for example, drug delivery, scaffolding for tissue engineering and wound dressing.