Influences of mechanical properties and permeability on chitosan nano/microfiber mesh tubes as a scaffold for nerve regeneration

摘要

We have developed chitosan nonwoven micro/ nanofiber mesh tubes and examined the effects of their mechanical strength and permeability on nerve regeneration. Chitosan nano/microfibrous tubes with a deacetyla-tion rate (DAc) of 78 percent or 93 percent were prepared by electro-spinning. A chitosan film tube with a DAc of 93 percent was also fabricated and combined with the nano/microfibrous tubes to form bilayered tubes with a nano/microfiber mesh inner structure and a film outer layer. Nano/microfiber mesh tubes with a DAc of 78 percent or 93 percent, bilayered tubes with a nano/microfiber mesh inner structure with a DAc of 78 percent or 93 percent and a film outer layer with a DAc of 93 percent, and film tubes with a DAc of 93 percent were each tested as bridge grafts into injured rat sciatic nerve. Isografting was performed as a control. Although the functional recovery of motor activity was delayed in each group, sensory function reemerged first in the isograft group followed by the group receiving nano/microfiber mesh tubes with a DAc of 93 percent. Histological analysis was consistent with these results. The chitosan nano/microfiber mesh tubes with a DAc of 93 percent have sufficient mechanical properties to preserve tube space, provide a better scaffold for cell migration and attachment, and facilitate humoral permeation to enhance nerve regeneration.