LOW-DOSE RADIATION STERILIZATION

环氧乙烷（ETO）和伽马辐照（GR）是生物医学行业最常用的设备灭菌方法。然而，ETO和GR的使用可能受到限制，因为(1)某些辐射敏感装置会降解，例如由聚丙烯（PP）和可吸收聚酯制成的装置；(2) ETO及其有毒残留物灭菌不完全；(3)ETO的毒性和易爆性给灭菌设施带来的危害。最近出现的一种新型放射化学灭菌（RC-S）工艺，包括可控制释放的甲醛和低剂量（等于或小于7.5 KGy） GR的组合，以及PP和可吸收缝合线的重要性，证明了进行拟议研究的合理性。第一阶段的目标是确定灭菌的可行性，放射化学，PP和聚乙二醇（PG），作为一个密封包装的可吸收缝合线，而不影响其体内和体外性能。I期计划包括：(1)使用RC-S的现有数据来确定PP和PG缝合线的无菌性，以及氮气下5和7.5 Kgy辐照对箔包装拉伸性能的影响；(2)测定包装和缝合线中不同成分的甲醛残留量（如有）；(3)使用针线重复片段1并测定对针线性能的影响；(4)使用两种尺寸的PP和PG缝线以选定剂量进行第1段，并在3周内评估其体内性能；(5)分析结果并选择最佳包装和灭菌条件范围，以验证PP和PG缝合线的工艺。II期研究将包括(1)确定RC-S实验变量的影响；(2)评估RC-S工艺对复杂设备的适用性；(3)确定灭菌包装中有害甲醛的含量和包装的稳定性；(4)启动FDA审批程序。拟议的商业应用：第一阶段成功的主要结果是证明了使用放射化学工艺灭菌聚丙烯和聚乙醇酸缝合线的可行性，而不会影响其体外和体内性能和包装成分。第一阶段的结果将为第二阶段的工艺开发和验证提供基础数据。长期影响将是为辐射敏感装置提供一种新的低剂量辐射工艺，这是灭菌技术的一个重要里程碑。

Ethylene oxide (ETO) and gamma-irradiation (GR) are most commonly used for device sterilization by the biomedical industry. However, use of ETO and GR can be limited because of (l) degradation of certain radiation- sensitive devices such as those made of polypropylene (PP) and absorbable polyesters; (2) incomplete sterilization with ETO and its toxic residues, and (3) hazards in the sterilization facility due to the toxic and explosive nature of ETO. The recent availability of a novel radiochemical sterilization (RC-S) process comprising a combination of a controllably released formaldehyde, and low-dose (equal to or less than 7.5 KGy) GR, and importance of PP and absorbable sutures justified pursuing the proposed study. Phase I objective is to determine the feasibility to sterilize, radiochemically, PP and polyglycolide (PG), as an absorbable suture in a sealed package without compromising, significantly, its in vivo and in vitro properties. Phase I plans entail (1) using available data on RC-S to determine of PP and PG sutures sterility and effect of 5 and 7.5 Kgy irradiation, under nitrogen, on tensile properties in a foil package; (2) determining amount of residual formaldehyde (if any) in the different components of the package and suture; (3) repeating segment 1 using needled sutures and determining effect on needle properties; (4) conducting segment l at selected doses using two sizes of PP and PG sutures and evaluate their in vivo performance over a 3-week period; and (5) analyzing the results and selecting an optimum range of conditions for packaging and sterilization toward validating the process for PP and PG sutures in Phase II. Phase II study will include (l) determining effects of RC-S experimental variables; (2) assessing applicability of the RC-S process to complex devices; (3) ascertaining absence of harmful formaldehyde levels in sterilized packages and package stability; and (4) initiating the FDA approval process. PROPOSED COMMERCIAL APPLICATIONS: Primary outcome of a successful Phase I is demonstrating feasibility of sterilizing polypropylene and polyglycolide sutures using the radiochemical process without compromising their in vitro and in vivo performance and package components. Phase I results will provide basic data for process development and validation in Phase II. The long-term impact will be the availability of a new, low-dose radiation process for radiation-sensitive devices which represent a major milestone in sterilization technology.