Biodegradable zinc (Zn) and Zn-based alloys have been recognized as promising biomaterials for biomedical implants. Sterilization is an essential step in handling Zn-based implants before their use in clinical practice and there are various sterilization methods are available. However, how these treatments influence the Zn-based biomaterials remains unknown and is of critical relevance. In this study, three commonly-applied standard sterilization methods, namely gamma irradiation, hydrogen peroxide gas plasma and steam autoclave, were used on pure Zn and Zn3Cu (wt%) alloy. The treated Zn and ZnCu alloy were investigated to compare the different influences of sterilizations on surface characteristics, transient and long-term degradation behavior and cytotoxicity of Zn and Zn alloy. Our results indicate that autoclaving brought about apparently a formation of inhomogeneous zinc oxide film whereas the other two methods produced no apparent alterations on the material surfaces. Consequently, the samples after autoclaving showed significantly faster degradation rates and more severe localized corrosion, especially for the ZnCu alloy, owing to the incomplete covering and unstable zinc oxide layer. Moreover, the autoclave-treated Zn and ZnCu alloy exhibited apparent cytotoxic effects towards fibroblasts, which may be due to the excessive Zn ion releasing and its local concentration exceeds the cellular tolerance capacity. In contrast, gamma irradiation and hydrogen peroxide gas plasma had no apparent adverse effects on the biodegradability and cytocompatibility of Zn and ZnCu alloy. Our findings may have significant implications regarding the selection of suitable sterilization methods for Zn-based implant materials among others.

可生物降解的锌 (Zn) 和锌基合金已被公认为有前途的生物医学植入物生物材料。在临床实践中使用锌基植入物之前，消毒是处理锌基植入物的重要步骤，并且有多种消毒方法可用。然而，这些处理如何影响锌基生物材料仍然未知，并且具有重要的相关性。在这项研究中，三种常用的标准灭菌方法，即伽马辐射、过氧化氢气体等离子体和蒸汽高压灭菌器，用于纯 Zn 和 Zn 3Cu (wt%) 合金。处理后的 Zn 和 Zn研究了铜合金，以比较灭菌对锌和锌合金的表面特性、瞬时和长期降解行为以及细胞毒性的不同影响。我们的结果表明，高压灭菌明显形成了不均匀的氧化锌膜，而其他两种方法在材料表面没有产生明显的变化。因此，高压灭菌后的样品表现出明显更快的降解速率和更严重的局部腐蚀，尤其是对于 Zn Cu 合金，由于不完全覆盖和不稳定的氧化锌层。此外，高压釜处理的 Zn 和 ZnCu合金对成纤维细胞表现出明显的细胞毒作用，这可能是由于过量的Zn离子释放及其局部浓度超过细胞耐受能力所致。相比之下，γ辐照和过氧化氢气体等离子体对锌和锌铜合金的生物降解性和细胞相容性没有明显的不利影响。我们的发现可能对为锌基植入材料选择合适的灭菌方法具有重要意义。