Bottom Effect in Atomic Force Microscopy Nanomechanics
Bottom Effect in Atomic Force Microscopy Nanomechanics
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DOI：
10.1002/smll.202000269
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发表时间：
2020-08-06
期刊：
影响因子：
13.3
通讯作者：
Cea, Pilar
中科院分区：
文献类型：
--
作者：
Chiodini, Stefano;Ruiz-Rincon, Silvia;Cea, Pilar
在这项工作中，刚性基板上的样品的杨氏模量的测定，所谓的bottom效应伪影的影响，证明了由原子力显微镜力谱实验。纳米力学性能的单组分支持的脂质膜（SLM）表现出两种不同厚度的区域进行了研究：虽然标准的接触力学模型（Sneddon）提供了两种不同的弹性模量为这两种形态，它表明，加西亚的底部效应伪影校正产生一个独特的值，预期的内在材料属性。值得注意的是，它表明，接触半径（而不仅仅是压痕）和样品厚度之间的比率是解决底部效应伪影的相关性的关键参数。实验结果验证了有限元方法模拟提供了坚实的支持加西亚的理论。所研究的材料的两亲性质是几种脂质的代表，这表明该结果对确定SLM的正确杨氏模量具有深远的意义。加西亚的底部效应伪影校正的通用性允许其应用于每一种支持的软膜。
In this work, the influence of the rigid substrate on the determination of the sample Young's modulus, the so-calledbottom-effect artifact, is demonstrated by an atomic force microscopy force-spectroscopy experiment. The nanomechanical properties of a one-component supported lipid membrane (SLM) exhibiting areas of two different thicknesses are studied: While a standard contact mechanics model (Sneddon) provides two different elastic moduli for these two morphologies, it is shown that Garcia's bottom-effect artifact correction yields a unique value, as expected for an intrinsic material property. Remarkably, it is demonstrated that the ratio between the contact radius (and not only the indentation) and the sample thickness is the key parameter addressing the relevance of the bottom-effect artifact. The experimental results are validated by finite element method simulations providing a solid support to Garcia's theory. The amphiphilic nature of the investigated material is representative of several kinds of lipids, suggesting that the results have far reaching implications for determining thecorrectYoung's modulus of SLMs. The generality of Garcia's bottom-effect artifact correction allows its application to every kind of supported soft film.