Fabrication of novel biomaterials through molecular self-assembly

Abstract

Two complementary strategies can be used in the fabrication of molecular biomaterials. In the 'top-down' approach, biomaterials are generated by stripping down a complex entity into its component parts (for example, paring a virus particle down to its capsid to form a viral cage). This contrasts with the 'bottom-up' approach, in which materials are assembled molecule by molecule (and in some cases even atom by atom) to produce novel supramolecular architectures. The latter approach is likely to become an integral part of nanomaterials manufacture and requires a deep understanding of individual molecular building blocks and their structures, assembly properties and dynamic behaviors. Two key elements in molecular fabrication are chemical complementarity and structural compatibility, both of which confer the weak and noncovalent interactions that bind building blocks together during self-assembly. Using natural processes as a guide, substantial advances have been achieved at the interface of nanomaterials and biology, including the fabrication of nanofiber materials for three-dimensional cell culture and tissue engineering, the assembly of peptide or protein nanotubes and helical ribbons, the creation of living microlenses, the synthesis of metal nanowires on DNA templates, the fabrication of peptide, protein and lipid scaffolds, the assembly of electronic materials by bacterial phage selection, and the use of radiofrequency to regulate molecular behaviors.

A nanomechanical interface to rapid single-molecule interactions

“…P recise recognition mechanisms of biological molecules offer a tremendous potential for the assembly [1][2][3] , imaging 4,5 and analysis of complex biological materials 6 . Single-molecule force spectroscopy (SMFS) experiments with the atomic force microscope (AFM) 7 have demonstrated the potential of intermolecular forces to be used for chemically specific nanoscale imaging 8 , manipulation 9 , directed assembly 10 , and biophysical studies of deformation and failure of biomolecules 11 .…”

Super-resolution surface mapping using the trajectories of molecular probes

“…In contrast with the situation for 'hard' materials in vacuo, where numerous analytical methods exist to detect and map atomic species, there is a dearth of appropriate characterization methods for 'soft' molecular materials, where noncovalent molecular interactions are paramount, and applications often involve 'wet' conditions. Methods based on scanning probe microscopy (SPM, for example, chemical force microscopy [9][10][11] ) can provide some local information about surface interactions. However, SPM has significant limitations in this regard, not the least of which is the need to understand the surface chemistry of the probe tip itself.…”

Heart regeneration after myocardial infarction using synthetic biomaterials

“…Self-assembling is a process that is mediated by non-covalent interaction between molecules via ionic bonds, hydrogen bonding, hydrophobic interactions and van der Waal interactions [60]. Self-assembling peptides are normally 8-16 amino acids long and they are composed of alternating hydrophilic and hydrophobic residues that form a stable hydrogel of flexible nanofibers (NFs) upon exposure to physiological salt concentration or pH [61]. This is the case with the self-assembling polypeptide RAD16-II and its derivates.…”