title: Synthesis, characterization, and application of reversible PDLLA-PEG-PDLLA copolymer thermogels in vitro and in vivo.
abstract: In this study, a series of injectable thermoreversible and thermogelling PDLLA-PEG-PDLLA copolymers were developed and a systematic evaluation of the thermogelling system both in vitro and in vivo was performed. The aqueous PDLLA-PEG-PDLLA solutions above a critical gel concentration could transform into hydrogel spontaneously within 2 minutes around the body temperature in vitro or in vivo. Modulating the molecular weight, block length and polymer concentration could adjust the sol-gel transition behavior and the mechanical properties of the hydrogels. The gelation was thermally reversible due to the physical interaction of copolymer micelles and no crystallization formed during the gelation. Little cytotoxicity and hemolysis of this polymer was found, and the inflammatory response after injecting the hydrogel to small-animal was acceptable. In vitro and in vivo degradation experiments illustrated that the physical hydrogel could retain its integrity as long as several weeks and eventually be degraded by hydrolysis. A rat model of sidewall defect-bowel abrasion was employed, and a significant reduction of post-operative adhesion has been found in the group of PDLLA-PEG-PDLLA hydrogel-treated, compared with untreated control group and commercial hyaluronic acid (HA) anti-adhesion hydrogel group. As such, this PDLLA-PEG-PDLLA hydrogel might be a promising candidate of injectable biomaterial for medical applications.
authors.affiliation: State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, 610041, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Shi
authors.affiliation: State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, 610041, China.
authors.forename: Ya-Li
authors.initials: YL
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, 610041, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Qu
authors.affiliation: State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, 610041, China.
authors.forename: Jin-Feng
authors.initials: JF
authors.lastname: Liao
authors.affiliation: State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, 610041, China.
authors.forename: Bing-Yang
authors.initials: BY
authors.lastname: Chu
authors.affiliation: State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, 610041, China.
authors.forename: Hua-Ping
authors.initials: HP
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, 610041, China.
authors.forename: Feng
authors.initials: F
authors.lastname: Luo
authors.affiliation: State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, and Collaborative Innovation Center for Biotherapy, Chengdu, 610041, China.
authors.forename: Zhi-Yong
authors.initials: ZY
authors.lastname: Qian
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000494:pharmacology; D004195:Disease Models, Animal; D005260:Female; D020100:Hydrogels / Q000138:chemical synthesis* / Q000737:chemistry*; D007279:Injections, Subcutaneous; D008807:Mice, Inbred BALB C; D008823:Micelles; D010537:Peritoneum / Q000187:drug effects / Q000473:pathology; D044367:Phase Transition; D011091:Polyesters / Q000138:chemical synthesis* / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000138:chemical synthesis* / Q000737:chemistry*; D017207:Rats, Sprague-Dawley; D012212:Rheology; D013696:Temperature; D000267:Tissue Adhesions / Q000517:prevention & control
chemical_list: D001672:Biocompatible Materials; D020100:Hydrogels; D008823:Micelles; D011091:Polyesters; D011092:Polyethylene Glycols; C033616:poly(lactide)