Collagen/silica nanocomposites and hybrids for bone tissue engineering

Abstract

Collagen is increasingly attracting attention for bone tissue engineering applications. However, due to its low mechanical properties, applications including mechanical loads or requiring structural integrity are limited. To tackle this handicap, collagen can be combined with (nanoscale) silica in a variety of composite materials that are attractive for bone tissue engineering. Considering research carried out in the past 15 years, this article reviews the literature discussing the development of silica/collagen composites that have been synthesized by adding silica from different sources as inorganic bioactive material to collagen as organic matrix. Different routes for the fabrication of collagen/silica composites are presented, focusing on nanocomposites. In vitro cell bioactivity studies demonstrated the osteogenic and, in some cases, angiogenic potential of the composites. Relevant in vivo studies discussing integration of the materials in bone tissue are discussed. Due to the understanding of possible interaction between silicon species and collagen, the effect of different silica precursors on the collagen self-assembly process is also discussed. On the basis of literature results and as discussed in this review, collagen/ silica nanocomposites and hybrids represent attractive biomaterials for bone regeneration applications.

Combining Collagen and Bioactive Glasses for Bone Tissue Engineering: A Review

“…In the present paper, a complete review of the literature on the development, characterization, and application of COL‐based composites containing BG inclusions is presented, with specific focus on their application in bone tissue engineering. This review complements our previous report, in which we have discussed in detail silica containing COL‐based nanocomposites …”

Collagen scaffolds as a tool for understanding the biological effect of silicates

“…It is likely that the local silicate concentration is higher than if the same amount of silicate were added to cell culture medium. Further, it is not known if the form of silicate is altered during scaffold production, or in what form the silicate interacts with cells, making comparison to systems based on soluble silicates difficult [11]. However, we have shown that incorporation of 0.21 wt% silicate within scaffolds was sufficient to influence mRNA levels, without affecting the scaffold stability.…”

“…In Bioglasses, release of silicate and calcium ions drives osteoblastic differentiation, but the effects of individual components remain unclear [4,[6][7][8]. Many factors contribute to this variability including cell passage number and the silicate source [9][10][11].…”

Recent advances on injectable nanocomposite hydrogels towards bone tissue rehabilitation

“…15 Apart from exhibiting sufficient biocompatibility, a scaffold is expected to be structurally similar to native bone tissue, that is, in terms of porosity, mechanical properties, weight, etc. 16 Depending upon the material and its properties, bone scaffolds may be broadly divided into degradable type and non-degradable type. 2 Non-degradable bone scaffolds usually require both primary and revision surgeries, whereas, in the case of degradable scaffolds, revision surgery is not required as these types of scaffolds degrade within the body concerning time.…”