title: Injectable pullulan hydrogel for the prevention of postoperative tissue adhesion.
abstract: Methods for reducing and preventing postoperative abdominal adhesions have been researched for decades; however, despite these efforts, the formation of postoperative peritoneal adhesions is continuously reported. Adhesions cause serious complications such as postoperative pain, intestinal obstruction, and infertility. Tissue adhesion barriers have been developed as films, membranes, knits, sprays, and hydrogels. Hydrogels have several advantages when used as adhesion barriers, including flexibility, low tissue adhesiveness, biodegradability, and non-toxic degraded products. Furthermore, compared with preformed hydrogels, injectable hydrogels can fill and cover spaces of any shape and do not require a surgical procedure for implantation. In this study, pullulan was modified through reaction with 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) to introduce carboxyl and phenyl groups as crosslinking sites. The grafting of tyramine on pullulan allows crosslinking branches on pullulan backbone. We successfully fabricated pullulan hydrogel with an enzymatic reaction using horseradish peroxidase (HRP) and hydrogen peroxide (H2O2). The chemical structure of modified pullulan was analyzed with ATR-FTIR and (1)H NMR spectroscopies. Rheological properties were tested by measuring storage modulus with varying H2O2, HRP, polymer solution concentrations and tyramine substitution rates. Cell viability and animal tests were performed. The modified pullulan hydrogel is an invaluable advance in anti-adhesion agents.
authors.affiliation: Department of Polymer Science and Engineering, Kumoh National Institute of Technology, Gumi, Gyeongbuk 39177, Republic of Korea.
authors.forename: Sumi
authors.initials: S
authors.lastname: Bang
authors.affiliation: Department of Polymer Science and Engineering, Kumoh National Institute of Technology, Gumi, Gyeongbuk 39177, Republic of Korea.
authors.forename: Eungjae
authors.initials: E
authors.lastname: Lee
authors.affiliation: Department of Polymer Science and Engineering, Kumoh National Institute of Technology, Gumi, Gyeongbuk 39177, Republic of Korea.
authors.forename: Young-Gwang
authors.initials: YG
authors.lastname: Ko
authors.affiliation: R&D Center, Wonbiogen Inc., Gumi, Gyeongbuk 39372, Republic of Korea.
authors.forename: Won Il
authors.initials: WI
authors.lastname: Kim
authors.affiliation: Department of Polymer Science and Engineering, Kumoh National Institute of Technology, Gumi, Gyeongbuk 39177, Republic of Korea. Electronic address: ohkwon@kumoh.ac.kr.
authors.forename: Oh Hyeong
authors.initials: OH
authors.lastname: Kwon
mesh_terms: D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D005936:Glucans / Q000737:chemistry* / Q000494:pharmacology*; D006801:Humans; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D007267:Injections; D008297:Male; D011183:Postoperative Complications / Q000517:prevention & control*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012212:Rheology; D000267:Tissue Adhesions / Q000517:prevention & control*; D014867:Water / Q000737:chemistry
chemical_list: D005936:Glucans; D014867:Water; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; C009109:pullulan
keywords: Anti-adhesion barrier; Enzymatic reaction; Hydrogel; Pullulan