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Atomic force microscopy (AFM) indentation experiments are commonly used to study the mechanical properties of graphene, such as Young's modulus and strength. However, applied AFM indentation forces on suspended graphene beams or ribbons are typically limited to several tens of nanonewtons due to the extreme thinness of graphene and their sensitivity to damage caused by the AFM tip indentation. Herein, graphene ribbons with a Si mass attached to their center position are employed, allowing us to introduce an unprecedented, wide range of AFM indentation forces (0–6800 nN) to graphene ribbons before the graphene ribbons are ruptured. It is found that the Young's modulus of double-layer graphene ribbons decreases as the applied AFM indentation force is larger than ≈3000 nN, which indicates that the stiffness of double-layer graphene ribbons remains constant before exposing them to AFM indentation forces larger than ≈3000 nN., QC 20220930

This thesis developed a numerical model for simulating red blood cell shape and deformability. The model was applied to understand how changes in membrane mechanical properties impact upon the cells' exhibited shape and ability to deform. This was done in the context of two loading scenarios, indentation and stretching. The project highlights some important factors to consider when developing experimental methods that quantify red blood cell deformability, of interest in transfusion medicine and for the diagnosis of certain diseases.