Biodegradable positively charged ion exchange beads: a novel biomaterial for enhancing soft tissue repair

Previous work in the area of vulnerary agents is extensive. One material of focus has been positively charged ion exchange beads, which have been shown to promote a variety of wound-healing responses in several models. The goal of this work was to improve upon the clinical utility of positively charged dextran beads by creating a biodegradable version that maintains the material's inherent efficacy. A chemical method consisting of a sodium periodate oxidation was used to create a degradable diethylaminoethanol crosslinked dextran bead. The ability of this process to create a degradable bead was verified in vitro and in vivo. Furthermore, efficacy was shown in a rat linear incision model for a variety of beads exhibiting different degradation rates. The results show that efficacy is maintained by a degradable bead, but there is a diminution of the magnitude of the response as the mass loss rate is increased. Efficacy also was investigated for a moderate but completely degrading bead material over time and dose. Wound breaking strength was evaluated at days 7, 10, 14, 21, and 28 for degradable beads at doses of 10 mg/mL and 50 mg/mL. Although little difference in efficacy was noted for the increased dose, statistically significant increases over control were seen at days 7, 10, and 14 for the 10 mg/mL dose and at days 10 and 14 for the 50 mg/mL dose. At days 21 and 28 there were no differences between treated and control wounds.