Wood Jonathan, Palms Dennis, Dabare Ruvini, Vasilev Krasimir, Bright Richard
Future Industries Institute, University of South Australia, Mawson Lakes, Adelaide, SA 5095, Australia.
College of Medicine and Public Health, Flinders University, Bedford Park, SA 5042, Australia.
Nanomaterials (Basel). 2024 Sep 11;14(18):1475. doi: 10.3390/nano14181475.
Nanoparticle adhesion to polymer and similar substrates may be prone to low nano-Newton forces, disrupting the surface bonds and patterning, potentially reducing the functionality of complex surface patterns. Testing this, a functionalised surface reported for biological and medical applications, consisting of a thin plasma-derived oxazoline-based film with 68 nm diameter covalently bound colloidal gold nanoparticles attached within an aqueous solution, underwent nanomechanical analysis. Atomic Force Microscopy nanomechanical analysis was used to quantify the limits of various adaptations to these nanoparticle-featured substrates. Regular and laterally applied forces in the nano-Newton range were shown to de-adhere surface-bound gold nanoparticles. Applying a nanometre-thick overcoating anchored the nanoparticles to the surface and protected the underlying base substrate in a one-step process to improve the overall stability of the functionalised substrate against lower-range forces. The thickness of the oxazoline-based overcoating displayed protection from forces at different rates. Testing overcoating thickness ranging from 5 to 20 nm in 5 nm increments revealed a significant improvement in stability using a 20 nm-thick overcoating. This approach underscores the importance of optimising overcoating thickness to enhance nanoparticle-based surface modifications' durability and functional integrity.
纳米颗粒与聚合物及类似底物的粘附可能容易受到低纳牛顿力的影响，从而破坏表面键和图案，有可能降低复杂表面图案的功能。为测试这一点，对一种用于生物和医学应用的功能化表面进行了纳米力学分析，该表面由一层薄的基于等离子体的恶唑啉薄膜组成，在水溶液中有直径68纳米的共价结合胶体金纳米颗粒附着在其中。原子力显微镜纳米力学分析用于量化对这些具有纳米颗粒特征的底物的各种适应性极限。结果表明，在纳牛顿范围内的常规和横向作用力会使表面结合的金纳米颗粒脱附。施加一层纳米厚的外涂层可将纳米颗粒固定在表面，并在一步过程中保护下面的基础底物，以提高功能化底物对较低范围力的整体稳定性。基于恶唑啉的外涂层厚度对力的防护速率不同。以5纳米为增量测试5至20纳米范围内的外涂层厚度，结果显示使用20纳米厚的外涂层时稳定性有显著提高。这种方法强调了优化外涂层厚度对于提高基于纳米颗粒的表面改性的耐久性和功能完整性的重要性。
