Electrospinning allows to control the size and geometry of the fibers. Nanofiber alignment opens the application to several fields such as surgical sutures, tendon and muscle implants.
Electrospun aligned fiber bundles represent a promising way to produce surgical sutures. Commercially available Vicryl sutures are based on PLGA, a material that is very often spun for research purposes and has promising clinical applications. Electrospun nanofibers are already proven to have a benign inflammatory response and can be loaded with drugs and antibiotics. For example, PLLA/PEG electrospun sutures filled with levofloxacin were proved to release the antibiotics for 2 months, exert the antibacterial activity and have an inflammatory reaction comparable to nylon sutures. Electrospun PLGA sutures loaded with bupivacaine HCl helped in reducing post-operative discomfort and the need of other form of anesthesia. After an initial burst release over 2 days, the anesthetic was linearly released up to day 7 and at day 12, the entire drug amount was eluted. It is a very promising option although the suture strength must be improved in order to match with the commercial PLGA sutures (Vicryl, 30N).
Electrospun bundles can be applied in tendon regeneration. Ligament and tendon ECM consists of longitudinally aligned nanofibers. Electrospinning allows to mimic the ECM in vivo state and this is proven to be beneficial as physical stimulus for cells.
Muscular tissue is another tissue based on aligned specialized nanofibers. Several studies have proven that electrospinning, by controlling material composition and fiber organization, can provide guidance for cell alignment and expression to myoblast markers without the use of chemical cues or fluids. Already in 2003 a patent described several ways of producing electrospun muscle implants and even the transition between muscle and tendon based on collagen type I and III alone or blended with biocompatible polymers such as PVA, PLA, PGA, PEO, etc. The muscle implant described in the patent comprise an extracellular matrix based on electrospun nanofibers, the tendon is made by extruded fibers and a layer or multilayers of muscle cells are disposed on the extracellular electrospun matrix.