In vitro degradation profiles and in vivo biomaterial –tissue interactions of microwell array delivery devices

AbstractTo effectively apply microwell array cell delivery devices their biodegradation rate must be tailored towards their intended use and implantation location. Two microwell array devices with distinct degradation profiles, either suitable for the fabrication of retrievable systems in the case of slow degradation, or cell delivery systems capable of extensive remodeling using a fast degrading polymer, were compared in this study. Thin films of a poly(ethylene glycol) ‐poly(butylene terephthalate) (PEOT‐PBT) and a poly(ester urethane) were evaluated for their in vitro degradation profiles over 34 weeks incubation in PBS at different pH values. The PEOT‐PBT films showed minimal in vitro degradation over time, while the poly(ester urethane) films showed ext ensive degradation and fragmentation over time. Subsequently, microwell array cell delivery devices were fabricated from these polymers and intraperitoneally implanted in Albino Oxford rats to study their biocompatibility over a 12‐week period. The PEOT‐PBT implants shown to be capable to mainta in the microwell structure over time. Implants provoked a foreign body response resulting in multilayer fibrosis that integrated into the surrounding tissue. The poly(ester urethane) implants showed a loss of the microwell structures over time, as well as a fibrotic response until the onset of fragm entation, at least 4 weeks post implantation. It was concluded that the PEOT‐PBT implants could be used as retrievabl...

Source: Journal of Biomedical Materials Research Part B: Applied Biomaterials - July 15, 2020 Category: Materials Science Authors: Elahe Hadavi, Rick H.W. Vries, Alexandra M. Smink, Bart Haan, Jeroen Leijten, Leendert W. Schwab, Marcel H.B.J. Karperien, Paul Vos, Pieter J. Dijkstra, Aart A. Apeldoorn Tags: ORIGINAL RESEARCH REPORT Source Type: research