Biological materials and molecular biomimetics – filling up the empty soft materials space for tissue engineering applications

The discovery and molecular (genetic) characterization of novel biological materials offers great potential to expand the range of soft materials used for biomedical applications.

Molecular biomimetics: nanotechnology and bionanotechnology using genetically engineered peptides

Nature provides inspiration for designing materials and systems that derive their functions from highly organized structures. Biological hard tissues are hybrid materials having inorganics within a complex organic matrix, the molecular scaffold controlling the inorganic structures. Biocomposites incorporate both biomacromolecules such as proteins, lipids and polysaccharides, and inorganic materials, such as hydroxyapatite, silica, magnetite and calcite. The ordered organization of hierarchical structures in organisms begins via the molecular recognition of inorganics by proteins that control interactions and is followed by the highly efficient self-assembly across scales. Following the molecular biological principle, proteins could also be used in controlling materials formation in practical engineering via self-assembled, hybrid, functional materials structures. In molecular biomimetics, material-specific peptides could be the key in the molecular engineering of biology-inspired materials. With the recent developments of nanoscale engineering in physical sciences and the advances in molecular biology, we now combine genetic tools with synthetic nanoscale constructs to create a novel methodology. We first genetically select and/or design peptides with specific binding to functional solids, tailor their binding and assembly characteristics, develop bifunctional peptide/protein genetic constructs with both material binding and biological activity, and use these as molecular synthesizers, erectors and assemblers. Here, we give an overview of solid-binding peptides as novel molecular agents coupling bio- and nanotechnology.

Molecular Biomimetics: Genetic Synthesis, Assembly, and Formation of Materials Using Peptides

In nature, the molecular-recognition ability of peptides and, consequently, their functions are evolved through successive cycles of mutation and selection. Using biology as a guide, it is now possible to select, tailor, and control peptide–solid interactions and exploit them in novel ways. Combinatorial mutagenesis provides a protocol to genetically select short peptides with specific affinity to the surfaces of a variety of materials including metals, ceramics, and semiconductors. In the articles of this issue, we describe molecular characterization of inorganic-binding peptides; explain their further tailoring using post-selection genetic engineering and bioinformatics; and finally demonstrate their utility as molecular synthesizers, erectors, and assemblers. The peptides become fundamental building blocks of functional materials, each uniquely designed for an application in areas ranging from practical engineering to medicine.