In situ gellable sugar beet pectin via enzyme-catalyzed coupling reaction of feruloyl groups for biomedical applications

In situ gellable hydrogels are more attractive in many biomedical and biopharmaceutical applications than pre-formed hydrogels because they can be implanted simply by injection and allow homogeneous incorporation of bioactive materials. In this study, the potential suitability of in situ gellable sugar beet pectin (SBP) for biomedical and biopharmaceutical applications was investigated. SBP aqueous solution gelled within 1min after addition of appropriate amounts of horseradish peroxidase (HRP) and H ₂O ₂via HRP-catalyzed oxidative coupling reaction of feruloyl groups on SBP molecules. The resultant gels gradually degraded under simulated physiological condition. L929 fibroblast cells encapsulated in the gels were scarcely damaged during the gelation process. A subcutaneously injected mixture of SBP, HRP and H ₂O ₂ solutions successfully gelled, and the gel did not induce necrosis in the surrounding tissue 1week after implantation. These results demonstrate that the in situ gellable SBP gels are useful for biomedical and biopharmaceutical applications.