Transforming Nanofibers into Woven Nanotextiles for Vascular Application

Abstract

This study investigates the unique properties, fabrication technique, and vascular applications of woven nanotextiles made from low-strength nanoyarns, which are bundles of thousands of nanofibers. An innovative robotic system was developed to meticulously interweave nanoyarns in longitudinal and transverse directions, resulting in a flexible, but strong woven product. This is the only technique for producing seamless nanotextiles in tubular form from nanofibers. The porosity and the mechanical properties of nanotextiles could be substantially tuned by altering the number of nanoyarns per unit area. Investigations of the physical and biological properties of the woven nanotextile revealed remarkable and fundamental differences from its nonwoven nanofibrous form and conventional textiles. This enhancement in the material property was attributed to the multitude of hierarchically arranged nanofibers in the woven nanotextiles. This patterned woven nanotextile architecture leads to a superhydrophilic behavior in an otherwise hydrophobic material, which in turn contributed to enhanced protein adsorption and consequent cell attachment and spreading. Short-term in vivo testing was performed, which proved that the nanotextile conduit was robust, suturable, kink proof, and nonthrombogenic and could act as an efficient embolizer when deployed into an artery.

Structural and optical characterization of the crystalline phase transformation of electrospinning TiO2 nanofibres by high-temperatures annealing

“…TiO 2 nanofibres manufactured with the electrospinning technique and the solgel process provide the advantage of high porosity and a high surface area [22]. The electrospinning method continues to attract attention in research fields such as biotechnology, the textile industry and the environment where TiO 2 nanofibres are used [23][24][25][26].…”

Medical textiles

“…Attention is being paid to the suitability of biodegradable materials for stents, to circumvent the need for removal, but particular attention is needed to ensure, through optimisation, that a stent (knitted in this case) made from such a material (polylactic acid in this instance) can withstand the radial forces likely to be exerted over the required length of time [346]. Grafts/stents made from nanofibres which may be made from absorbable or non-absorbable polymers depending on the application [9] also appear to offer many advantages over those made from conventional yarns, not least because of their high degree of porosity, which, in the case of a tubular woven nanofibre graft could be adjusted by controlling thread density [347]. The yarns made from bundles of nanofibres are relatively fragile so great care had to be taken not to damage them during the (novel robotic) weaving process, but the resulting graft was robust, suturable, kink-proof, and non-thrombogenic.…”

Design, Development, and Evaluation of an Interwoven Electrospun Nanotextile Vascular Patch

“…This was explored by our group in developing nanotextile‐based small diameter vascular grafts by cylindrical weaving, utilizing nanofibrous yarns. [ 23,24 ] However, this technique could not be used to fabricate woven patch materials owing to the high radial stiffness of the conduit and the disentangling of woven yarns from the conduit when transformed into a patch. Hence, we hypothesize that the conventional plain weaving technique utilizing longitudinal (warp) and transverse (weft) nanofibrous yarns of similar diameter can yield a mechanically stable, tightly packed, and flexible patch, with a characteristic anisotropic stress–strain behavior.…”