Nanophase Materials

Abstract

Great strides are being made in our ability to synthesize and assemble nanoscale building blocks to create nanophase materials with novel properties and functionalities. The novel properties of nanostructures are derived from their confined sizes and their very large surface‐to‐volume ratios. The former give rise to unique size‐dependent properties in the nanoscale (1–100 nm) regime, while the latter give rise to the ability of nanoscale additions to conventional material matrices to dramatically change the host material's properties. Nanostructured surfaces have also been shown to elicit more favorable and selective biomolecule and cellular responses than surfaces at coarser length scales. The characteristics of nanophase materials are described and what is known about their interactions with proteins and cells is reviewed with extensive references. While many studies have been carried out to probe such interactions, we are still at a very early stage of understanding the fundamental issues controlling these interactions. Much careful work remains before these important interactions are fully understood so that they can be controlled to impact biomedicine to benefit society.

Influence of titania nanotopography on human vascular cell functionality and its proliferation in vitro

“…Protein adsorption on various nanosurfaces can be ascribed to several factors such as (i) surface area of Ti structures, (ii) wettability and surface energy, (iii) electrostatic interactions between protein molecules and Ti surface and (iv) the type and conformation of proteins. 13,37 A distinct difference can be noted in the total protein adsorbed on nanostructured Ti samples in comparison to bare control Ti. This is in correlation with the surface area and surface roughness measurements on various substrates.…”

“…However, the fact that nanostructuring provides enhanced protein adsorption on Ti offers a better stimulus that aids improved cellular interactions (adhesion and proliferation) on such surfaces, as against conventional Ti surfaces. 37 The conformation of the proteins is also a very important factor that influences initial cell adhesion. This in turn would create a more cytocompatible environment and provide increased viability of endothelial cells on the nanoleaves, nanopores and nanorods than on control Ti, while appropriate growth signals may be secreted for proliferation and differentiation of cells.…”

Unfolding of Ribonuclease A on Silica Nanoparticle Surfaces

“…Understanding the interaction of biomolecules with nanoscale surfaces is fundamentally important to the design and creation of hierarchical material assemblies and functional devices using biomolecules and to elucidate potential health effects, either positive or negative, of nanoscale materials at the molecular level. Proteins are known to undergo changes to their structures and stabilities upon adsorption onto macroscopic solid surfaces. , Such changes are strongly dependent on both the nature of the adsorbed proteins and the physicochemical characteristics of the solid surfaces. , At the nanoscale, an additional influence of the surface geometry is also known to play a role in governing protein structure and function. In particular, a high degree of surface curvature has been shown to promote increased stability of adsorbed proteins in comparison to macroscopic “flat” supports. − For example, lysozyme 5 and human carbonic anhydrase 6 retain a greater fraction of their native-like secondary and tertiary structures when adsorbed onto hydrophilic silica nanoparticles (NPs) than on conventional silica surfaces, presumably due to the high degree of surface curvature of the former relative to the latter.…”

“…1,2 Such changes are strongly dependent on both the nature of the adsorbed proteins and the physicochemical characteristics of the solid surfaces. 3,4 At the nanoscale, an additional influence of the surface geometry is also known to play a role in governing protein structure and function. In particular, a high degree of surface curvature has been shown to promote increased stability of adsorbed proteins in comparison to macroscopic "flat" supports.…”

The influence of polymeric component of bioactive glass‐based nanocomposite paste on its rheological behaviors and in vitro responses: Hyaluronic acid versus sodium alginate

“…Compared to conventional micro‐sized BGs which are prepared by melting processes, the use of nanosized BG particles which are produced by sol‐gel method can promote cellular functions (cell proliferation and activity, cell adhesion, and differentiation) resulting in enhanced biomineralization process . Moreover, Nanosized BGs exhibit superior specific surface area (SSA) that greatly accelerate deposition process of hydroxyapatite and hence tissue bonding ability …”