Chapter 2: Inorganic–Protein Hybrid Bionanostructures

Combining protein structures with inorganic components provides many new potential materials for biomedical, bioelectronic and biosensing applications. Various approaches can be taken for combining protein particles and inorganic materials, mostly associated with templating. Either the inorganic structure can be used as a template on which proteins can adhere, or the protein structure acts as the template for the deposition or inclusion of the inorganic material. On many occasions, protein assemblies are used that are composed of multiple protein subunits arranged either in a globular fashion of in an anisotropic arrangement including cage proteins and virus particles. Both the interior and exterior of these protein structure are targeted for confining inorganic materials such as metals, minerals and semiconductors. In this chapter, the general approaches are presented, together with recent advances in inorganic–protein hybrid nanoparticles, demonstrating the tremendous number of combinations that are possible and that not only is close control over the location where protein or inorganic material is deposited possible but also control over complex micro- and mesoscale morphologies can be achieved via protein–inorganic hybrid formation. Most approaches for modification involve synthetic chemistry; however, this can be directed and facilitated by incorporating reactive/functional peptide sequences via genetic modifications of the protein structure. The combination of synthetic chemistry and biotechnology has become one of the most often used combinations for the development of inorganic–protein hybrid structures.