Research
Grain Structure Mediated Protein Adsorption at Biointerfaces with Multi-scale Dimensionality
The successful integration of a biomedical device in a physiological environment is governed by surface and bulk properties of the material, and also depends on the interaction of the biomaterial with the surrounding physiological fluid and neighboring tissues. The first step in the integration of a biomedical device with the physiological system involves rapid adsorption of proteins on the surface. The next stage of integration is cell adhesion that occurs through the surface protein layer. Thus, protein adsorption occurs well before the arrival of cells, and cells primarily interact with the protein layer, rather than the actual biomaterial surface. Subsequently, the adsorbed proteins initiate physiological responses to biomaterials.
The adsorption of proteins from blood plasma to the biomaterial surface is a dynamic process during which proteins bind to the surface and rearrange. Adsorbed proteins act as pilots for cell adhesion, if they have the correct geometry to mediate cell attachment. Moreover, the structure and constitution of adsorbed plasma proteins on the surface governs events that follow adsorption, including cell attachment, proliferation, and tissue formation. Thus, the adsorption and self-assembly (microstructure) of proteins at biointerfaces, metallic or nonmetallic, which govern biological response is important.
The research interweaves materials science, nanotechnology, and biomedical engineering in the fundamental understanding of grain structure-induced self-assembly of plasma proteins on polycrystalline metallic surfaces from nanograined (NG) to coarse-grained (CG: grain or crystal size in the micrometer range) regime, which are radically different from the CG counterpart. The dynamics of protein self-assembly through the innovative application of atomic force microscopy (AFM) data to microrheology experiments obtained via the use of interfacial rod rheometer with high sensitivity and rapid response time are being captured.
