Unidirectional and sustainable release of NGF and BDNF from a chitosan gel-mediated multilayer ordered composite membrane in promoting both spinal cord and sciatic nerve injury repair.

To develop a scaffold suitable for simultaneous repair of both spinal cord injury (SCI) and sciatic nerve injury (SNI), we designed a multilayer composite membrane capable of unidirectional and sustained release of two factors: nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF). The membrane's morphology, mechanical properties, cytocompatibility, drug release kinetics, swelling, and degradation behavior were thoroughly characterized. Additionally, its ability to promote the differentiation of PC-12 cells was assessed.