Department of Bioengineering, Clemson University, United States; Clemson - Medical University of South Carolina Program in Bioengineering, Charleston, SC 29425, United States.
Department of Bioengineering, Clemson University, United States; Clemson - Medical University of South Carolina Program in Bioengineering, Charleston, SC 29425, United States.
Acta Biomater. 2021 Jun;127:242-251. doi: 10.1016/j.actbio.2021.03.053. Epub 2021 Mar 31.
Adhesion properties, which can vary with multiple factors, of silicone hydrogel contact lenses are important to their performance and comfort in the eye. In this study, we developed and used a simple, representative testing system and method to study the adhesive interactions of different silicone contact lenses (balafilcon A and senofilcon A) on polished titanium alloy and porcine whole eye cornea under dehydrating conditions. Adhesive interactions for senofilcon A varied by hydration state for both corneal and titanium adhesion, starting low, rising to a maximum and falling with dehydration time and dehydration state. Balafilcon A showed a rise and fall against titanium, but retained a relatively constant adhesive interaction with corneal tissue over dehydration time. Senofilcon A reached the highest adhesion forces (400 mN) within 5 to 10 min of testing against cornea, then dropped with time after that. Johnson-Kendall-Roberts (JKR) theory was applied to determine the surface energy of the lenses, and work of adhesion (WOA) was also determined for both lenses. Similar trends as observed with the force-hydration curves were seen with surface energy and work of adhesion as well (peak surface energy of 8 N/m and work of adhesion of 80 µJ for senofilcon A). Video imaging of the adhesive interactions showed significant corneal deformation taking place during testing, and post-test analysis shows damage to the corneal tissue. This method could be used to assess pre-clinical performance of long-lasting contact lenses and the role of hydration state. STATEMENT OF SIGNIFICANCE: Adhesion properties of contact lenses play significant roles in their performance and comfort in the eye. Adhesion is influenced by polymer chemistry, counterface materials and hydration state of the contact lenses. However, no test method has been developed to directly study the adhesion properties between contact lenses and corneal tissue during the dehydration process. Our work aims to fill this gap by developing testing and analysis methods for evaluating the adhesive interactions in vitro between contact lenses of different chemistries and properties and different counter surfaces under dehydrating conditions over time. Our study shows that adhesive interactions of contact lenses are highly dependent on polymer type, surface treatment, counterface material and hydration state.
硅水凝胶接触镜的粘附特性因多种因素而异，这些特性对其在眼睛中的性能和舒适度很重要。在这项研究中，我们开发并使用了一种简单、有代表性的测试系统和方法，研究了不同硅水凝胶接触镜（balafilcon A 和 senofilcon A）在脱水条件下对抛光钛合金和猪全眼角膜的粘附相互作用。在脱水过程中，senofilcon A 的角膜和钛的粘附水合状态不同，起始值较低，随脱水时间和脱水状态的增加而升高，达到最大值后下降。balafilcon A 与钛的粘附作用呈上升和下降趋势，但在脱水过程中与角膜组织的粘附作用相对稳定。senofilcon A 在与角膜接触后 5 到 10 分钟内达到最高粘附力（400 mN），然后随时间下降。Johnson-Kendall-Roberts（JKR）理论被应用于确定镜片的表面能，也确定了两种镜片的粘附功（WOA）。与力-水合曲线相似的趋势也出现在表面能和粘附功中（senofilcon A 的峰值表面能为 8 N/m，粘附功为 80 µJ）。对粘附相互作用的视频成像显示，在测试过程中角膜发生了明显的变形，测试后分析显示角膜组织受损。这种方法可以用来评估长效隐形眼镜的临床前性能和水合状态的作用。 意义声明：接触镜的粘附特性在其在眼睛中的性能和舒适度方面起着重要作用。粘附受聚合物化学、对物材料和接触镜的水合状态的影响。然而，尚未开发出直接研究接触镜和角膜组织在脱水过程中之间粘附特性的测试方法。我们的工作旨在通过开发测试和分析方法来填补这一空白，以评估不同化学性质和性能的接触镜与不同的对物表面在随时间脱水过程中的体外粘附相互作用。我们的研究表明，接触镜的粘附相互作用高度依赖于聚合物类型、表面处理、对物材料和水合状态。
