New tubular conduits have been developed for the regeneration of peripheral nerves and the repair of defects that are larger than 3 cm. The conduits consist of a combination of poly(L-lactide) nanofibers and chitosan composite fibers with chitin nanofibrils. In vitro studies were conducted to assess the biocompatibility of the conduits using human embryonic bone marrow stromal cells (FetMSCs). The studies revealed good adhesion and differentiation of the cells on the conduits just one day after cultivation. Furthermore, an in vivo study was carried out to evaluate motor-coordination disorders using the sciatic nerve functional index (SFI) assessment. The presence of chitosan monofibers and chitosan composite fibers with chitin nanofibrils in the conduit design increased the regeneration rate of the sciatic nerve, with an SFI value ranging from 76 to 83. The degree of recovery of nerve conduction was measured by the amplitude of M-response, which showed a 46% improvement. The conduit design imitates the oriented architecture of the nerve, facilitates electrical communication between the damaged nerve’s ends, and promotes the direction of nerve growth, thereby increasing the regeneration rate.

This study focused on a potential application of electrically conductive, biocompatible, bioresorbable fibers for tubular conduits aimed at the regeneration of peripheral nerves. The conducting, mechanical, and biological properties of composite fibers based on chitosan and single-walled carbon nanotubes were investigated in this paper. It was shown that introducing 0.5 wt.% of SWCNT into the composite fibers facilitated the formation of a denser fiber structure, resulting in improved strength (σ = 260 MPa) and elastic (E = 14 GPa) characteristics. Additionally, the composite fibers were found to be biocompatible and did not cause significant inflammation or deformation during in vivo studies. A thin layer of connective tissue formed around the fiber.

Tubular conduits have been developed for regeneration of peripheral nerves and repair of defects with a diastasis of more than 3 cm. The optimal conduit design included a tube based on poly(L-lactide) nanofibers and a filler in the form of composite chitosan fibers containing chitin nanofibrils. A study of motor coordination disorders was conducted in vivo using an assessment of the functional index of the sciatic nerve. It has been shown that the presence of chitosan monofilaments and chitosan composite fibers containing chitin nanofibrils in the conduit structure increased the rate of regeneration of the sciatic nerve; its functional index was 76–83. The degree of restoration of nerve conduction determined by measuring the amplitude of the M-response was 46%. The developed design of the conduit simulated the oriented architecture of the nerve, promoted electrical communication between the ends of the damaged nerve, and created conditions for increasing the rate of regeneration of nerve fibers and the direction of their growth.