Implantable medical devices must undergo thorough evaluation to ensure safety and efficacy before use in humans. If a device is designed to degrade, it is critical to understand the rate of degradation and the degradation products that will be released. Oxidative degradation is typically modeled in vitro by immersing materials or devices in hydrogen peroxide, which can limit further analysis of degradation products in many cases. Here we demonstrate a novel approach for testing the cytocompatibility of degradation products for oxidatively-degradable biomaterials where the materials are exposed to hydrogen peroxide, and then catalase enzyme is used to convert the hydrogen peroxide to water and oxygen so that the resulting aqueous solution can be added to cell culture media. To validate our results, expected degradation products are also synthesized then added to cell culture media. We used these methods to evaluate the cytocompatibility of degradation products from an oxidatively-degradable shape memory polyurethane designed in our lab and found that the degradation of these polymers is unlikely to cause a cytotoxic response in vivo based on the guidance provided by ISO 10993-5. These methods may also be applicable to other biocompatibility tests such as tests for mutagenicity or systemic toxicity, and evaluations of cell proliferation, migration, or gene and protein expression.

植入式医疗设备在用于人体之前必须经过彻底评估，以确保安全性和有效性。如果设备设计为可降解，则了解降解速率和将释放的降解产物至关重要。氧化降解通常在体外模拟通过将材料或设备浸入过氧化氢中，在许多情况下会限制对降解产物的进一步分析。在这里，我们展示了一种新颖的方法，用于测试可氧化降解的生物材料的降解产物的细胞相容性，该材料将材料暴露于过氧化氢，然后使用过氧化氢酶将过氧化氢转化为水和氧气，从而可将所得水溶液制成添加到细胞培养基中。为了验证我们的结果，还合成了预期的降解产物，然后将其添加到细胞培养基中。我们使用这些方法评估了由我们实验室设计的可氧化降解的形状记忆聚氨酯降解产物的细胞相容性，发现这些聚合物的降解不太可能引起细胞毒性反应根据ISO 10993-5提供的指导在体内进行。这些方法也可能适用于其他生物相容性测试，例如致突变性或全身毒性测试，以及细胞增殖，迁移或基因和蛋白质表达的评估。