To 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 extensive 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 maintain 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 fragmentation, at least 4 weeks post implantation. It was concluded that the PEOT‐PBT implants could be used as retrievable cell delivery devices while the poly(ester urethane) implants could be used for cell delivery devices that require remodeling within a 4–12 week period.

中文翻译：

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微孔阵列递送装置的体外降解曲线和体内生物材料-组织相互作用。

为了有效地应用微孔阵列细胞输送装置，它们的生物降解率必须针对它们的预期用途和植入位置进行调整。本研究比较了两种具有不同降解曲线的微孔阵列装置，它们要么适用于在缓慢降解的情况下制造可回收系统，要么能够使用快速降解聚合物进行广泛重塑的细胞递送系统。在不同 pH 值的 PBS 中孵育 34 周后，评估了聚（乙二醇）-聚（对苯二甲酸丁二醇酯）（PEOT-PBT）和聚（酯氨基甲酸酯）薄膜的体外降解曲线。PEOT-PBT 薄膜随着时间的推移显示出最小的体外降解，而聚（酯氨基甲酸酯）薄膜随着时间的推移显示出广泛的降解和碎裂。随后，微孔阵列细胞输送装置由这些聚合物制成，并植入白化牛津大鼠的腹腔内，以研究它们在 12 周内的生物相容性。PEOT-PBT 植入物显示能够随着时间的推移保持微孔结构。植入物引起异物反应，导致多层纤维化并融入周围组织。聚（酯氨基甲酸酯）植入物随着时间的推移显示出微孔结构的丢失，以及纤维化反应，直到植入后至少 4 周出现碎裂。得出的结论是，PEOT-PBT 植入物可用作可回收的细胞输送装置，而聚（酯）聚氨酯植入物可用于需要在 4-12 周内重塑的细胞输送装置。