Chitosan/collagen layer-by-layer deposition for improving the esophageal regeneration ability of nanofibrous mats

The morbidity of a diverse array of esophageal diseases has been increasing in recent years, and postoperative bacterial infection is a common potential risk. Current research on artificial esophageal stents is lacking and less than satisfactory. Artificial materials with excellent mechanical, antimicrobial, and cytocompatible properties at the same time still have great potential. In this study, chitosan (CS) and collagen (COL) were deposited on nylon 6 (N6)/silk fibroin (SF) composite nanofibers using layer-by-layer self-assembly (LBL). The obtained nanofibrous mats were characterized, and the results indicated that the surface morphology and hydrophilicity of the composite nanofibrous mats were obviously improved by the deposition of CS and COL. The mechanical properties of the composite nanofibrous mats were also improved after LBL modification. In addition, the LBL-structured nanofibrous mats possessed excellent antibacterial activity, reaching more than 90% inhibition of gram-positive and negative bacteria. The results of cell experiments indicated that the nanofibrous mats modified by CS and COL had excellent biocompatibility for promoting human esophageal epithelial cell adhesion and proliferation. In vivo animal experiments showed that the LBL-structured nanofibrous mats were beneficial to the healing of esophageal defects compared with the control group. In summary, LBL-structured nanofibrous mats are very promising materials for esophageal replacement to reduce the incidence of postoperative complications.