Hierarchical Micro- and Nanopatterning of Metallic Glass to Engineer Cellular Responses

Nano and micropatterning of biomaterials is a rapidly evolving technology used in the engineering sciences to control cell behavior. Specifically, altering the topographies and hence surface mechanical properties has been shown to induce changes in cell morphology and function. Here, we show a method for fabricating hierarchical micro- and nanopatterns of Pt_57.5Cu_14.7Ni_5.3P_22.5 (Pt-BMG) on the relevant length scales comparable to that of proteins and cells. Leveraging the amorphous nature of Pt-BMGs, we have a versatile toolbox to manipulate patterns on the nano/micro level and combine multiple length scales to examine specific cell responses. We assay the morphology of macrophages and fibroblasts, two cell types critical to the foreign body response. Furthermore, we show that nanotopography is critical for reducing macrophage fusion and that high levels of fusion on both unpatterned and micropatterned substrates can be mitigated with the addition of nanotopographical features. Interestingly, we show that the wetting ability of the substrates does not correlate with cellular responses on these substrates. Our results suggest that the different topographical length scales can be used to systematically affect corresponding cell-type-specific responses