Composite 3D vascularization by using sacrificial electrospun sub-micrometric fibres

The creation of an extensive vasculature in composite structures is a challenge. The Bond and White groups are pioneers of different methods to achieve composite vascularisation, all of them based on the removal of sacrificial micro-fibres previously embedded in a polymer matrix. We propose the use of electrospinning to produce sacrificial sub-micrometric fibres. Advantages derived by the use of this technique are: (i) the collection of fibres in form of a non-woven mat that can be easily embedded in a polymer matrix; (ii) the intrinsic morphology of the non-woven mat that resembles the blood vascular network of living system; (ii) the control of fibre diameters from undreds of nanometers to few micrometers; (iii) the control of fibre spatial arrangement. Here we present, as a proof of concept, the use of water soluble poly(ethylene oxide) electrospun fibres that can be easily embedded in a low-temperature thermoset polymer matrix and subsequently removed by simply immersing the composite in water. Fibres with different diameters can be used for generating vessels with different diameters. Moreover, non-woven mats either with a random fibre arrangement or with aligned fibres can be used to generate a biomimetic vasculature and unidirectional vessels, respectively. High-temperature thermoset polymer matrix can be similarly vascularized by a smart choice of electrospun fibre material.