检查了人工耳蜗生物材料上的光接枝两性离子水凝胶涂层的耐久性,以确定这些防污表面在插入和长期植入物使用过程中的生存能力。摩擦法用于确定两性离子涂层对不同水合水平的表面润滑性的影响,施加的法向力,和时间框架。此外,使用心轴弯曲研究了弯曲阻力。通过测定组织和处理表面之间的摩擦系数来评估离体耐久性。此外,使用尸体人类耳蜗测量人工耳蜗植入力。与未涂覆的PDMS相比,水合两性离子水凝胶涂层将摩擦阻力降低了约20倍,与未涂覆的系统相比,这导致在插入过程中涂覆的耳蜗植入物所经历的平均力明显更低。在弯曲力下,两性离子膜抵抗了长达60分钟的干燥失败。在水合的同时,在持续的力下,润滑性能保持20小时。对于松散交联的系统,即使在完全干燥后再水合后,薄膜仍保持稳定和润滑。在环境条件下,所有涂层在摩擦力下保持水合和功能至少30分钟,允许干燥。较低的交联密度显示最大的寿命。此外,光接枝的两性离子水凝胶样品在植入前后没有降解和几乎相同的润滑性的证据。这项工作表明,光接枝两性离子水凝胶涂层足够耐用,以保持生存能力之前,during,植入后。机械性能,包括大大增加的润滑性,在完全干燥和再水化后保存各种施加的力。此外,这种显著增强的润滑性转化为在植入物插入过程中显著降低的力,这将导致更少的创伤和瘢痕形成。
The durability of photografted zwitterionic hydrogel coatings on cochlear implant biomaterials was examined to determine the viability of these antifouling surfaces during insertion and long-term implant usage. Tribometry was used to determine the effect of zwitterionic coatings on the
lubricity of surfaces with varying hydration levels, applied normal force, and time frame. Additionally, flexural resistance was investigated using mandrel bending. Ex vivo durability was assessed by determining the coefficient of friction between tissues and treated surfaces. Furthermore, cochlear implantation force was measured using cadaveric human cochleae. Hydrated zwitterionic hydrogel coatings reduced frictional resistance approximately 20-fold compared to uncoated PDMS, which led to significantly lower mean force experienced by coated cochlear implants during insertion compared to uncoated systems. Under flexural force, zwitterionic films resisted failure for up to 60 min of desiccation. The large increase in
lubricity was maintained for 20 h under continual force while hydrated. For loosely cross-linked systems, films remained stable and lubricious even after rehydration following complete drying. All coatings remained hydrated and functional under frictional force for at least 30 min in ambient conditions allowing drying, with lower cross-link densities showing the greatest longevity. Moreover, photografted zwitterionic hydrogel samples showed no evidence of degradation and nearly identical
lubricity before and after implantation. This work demonstrates that photografted zwitterionic hydrogel coatings are sufficiently durable to maintain viability before, during, and after implantation. Mechanical properties, including greatly increased
lubricity, are preserved after complete drying and rehydration for various applied forces. Additionally, this significantly enhanced
lubricity translates to significantly decreased force during insertion of implants which should result in less trauma and scarring.