Synthesis of novel pH- and temperature-controlled composite hydrogels for tissue engineering

摘要

Synthetic hydrogels, such as polyethylene glycol) (PEG)-based hydrogels have been widely studied due to their attractive properties such as biocompatibility, adjustable mechanical properties, and ease of scaffold architecture modfication. However, the bio-inert characteristic of PEG causes PEG hydrogels themselves not supporting cell adhesion. Therefore, PEG synthetic hydrogels were developed by combining with natural hydrogels to overcome their poor properties. Hyaluronic acid (MA), a natural polymer, consisting of glucuronic acid and N-acetylglucosamine unit shows non-immunogenic, biodegradability, biocompatibility, excellent gel-forming, and regulated cellular behavior. Moreover, the carboxyl group of HA can be modified and crosslinked with other molecules, such as collagen, alginate, and galactose to form composite hydrogels. In this work, modified PEG-HA copolymer was corporated with thermo- and pH-sensitive oligomeric sulfamethazine (OSM). The carboxylic acid end group of OSM oligomer was coupled with hydroxy moiety of PEG-HA hydrogel. Moreover, the end group of HA can be linked with D-galactose. All structures were characterized by 1H-NMR spectroscopy and gel permeation chromatography (GPC). The polymer schematic of the final product is shown below, and this hydrogel has been utilized to produce materials for tissue engineering.