Hydroxypropylcellulose enhanced high viscosity endoscopic mucosal dissection intraoperative chitosan thermosensitive hydrogel

In order to prepare a submucosal injection agent that can gel during the endoscopic mucosal dissection (ESD) and still adhere to the wound surface after the surgery to reduce intraoperative and postoperative complications, a thermosensitive hydrogel based on chitosan/β-glycerophosphate (CS-GP) was constructed. Hydroxypropylcellulose (HPC) and collagen Ⅰ were added into the hydrogel to improve the adhesion ability, viscosity and biocompatibility. The effect of HPC on the viscosity, strength and bio-adhesion and collagen Ⅰ on the biocompatibility and promoting on the wound restoration were intensively studied. The results indicated that HPC and collagen Ⅰ will not obviously change pH of the system and the system was still physically cross-linked. HPC increased the initial gelation time but the time of the entire gelation process is shortened, especially the high-concentration HPC, and improved the mechanical strength obviously. The viscosity and the bio-adhesion of the CS-GP hydrogels were improved by the addition of HPC. Also, the mixed collagen Ⅰ offered good cytocompatibility. According to the results of cultured GES-1 cell, it can be seen that the addition of HPC and collagen Ⅰ does not inhibit cell proliferation, and shows more obvious protection on the cells under acidic conditions. All of these suggested that the application of this hydrogel were more promising in ESD surgery than which without HPC and collagen Ⅰ.