Why AFM modulus varies more in lower indentation depths?
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The variation in AFM modulus at lower indentation depths can be attributed to factors like tip geometry, surface tension effects, and the contact area between the tip and the sample. Tip sharpness influences the measured modulus, with sharper tips yielding higher values due to easier detection of small-scale stiffer areas within the sample. Surface tension, often neglected in traditional contact models, becomes significant in softer samples like living cells, leading to potential overestimation of the modulus at lower indent depths. Moreover, the contact area and average pressure exerted by the tip play crucial roles, with larger tip radii resulting in more evenly distributed pressure and potentially lower modulus values at lower indent depths. These combined factors contribute to the observed variability in AFM modulus measurements at shallow indentations.
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09 Apr 2017 2 Citations | The AFM modulus varies more in lower indentation depths due to the finite thickness film behavior being stiffer than thicker films, as shown in the simulation based on hyperelasticity. |
113 Citations | AFM modulus varies more in lower indentation depths due to the presence of actin filaments near the cell membrane, indicating non-homogeneity in cytoskeleton organization. |
43 Citations | Surface tension effects in AFM indentation cause overestimation of elastic modulus at lower depths. When considering surface tension, the modulus may not vary significantly with indentation depth. |
| AFM modulus varies more in lower indentation depths due to tip geometry affecting contact area and pressure distribution, influencing the measurement of mechanical properties in soft samples. | |
| AFM modulus varies more at lower indentation depths due to geometry approximations of probes, leading to erroneous data on soft materials; improved characterization methods are needed for accurate results. |
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