Bio-nanocomposites

Nowadays, bio-nanocomposites mimicking these natural materials have been prepared with the aim being to develop new biohybrids with improved mechanical properties together with biocompatibility and, in some cases, other interesting... 

As indicated above, the development of bio-nanohybrids by mimicking biomineralization represents an extraordinarily useful approach. This is, for instance, the case for those bio-nanocomposites based on bone biomimetic approaches, which show excellent structural properties and biocompatibility. They are prepared by... 

The aim of this chapter is to provide a general overview of the preparation and main characteristics of bio-nanohybrids, with emphasis on the different types of inorganic solids that can be involved in the formation of this class of materials. Special attention will be devoted to the diverse mechanisms that govern the interaction between the components of biohybrids, illustrating them with selected examples. Relevant features and potential or actual applications of recently developed bio-nanocomposites will be discussed on the basis of their structure-property relationships. 

Most of the bio-nanocomposites tested as implants for bone regeneration are based on the assembly of HAP nanoparticles with collagen, trying to reproduce the composition, biocompatibility and suitable mechanical properties of natural bone. 

Bio-nanocomposites based on calcium phosphates can perform other innovative fundions such as acting as a reservoir for the controlled release of bioadive compounds once the material is implanted in the bone defect. For instance, the incorporation of a morphogenetic protein that promotes bone regeneration in an HAP-alginate-collagen system [110] or a vitamin in a Ca-deficient HAP-chitosan nanocomposite [111] are recent examples of this kind of application. 

Chitosan-clay bio-nanocomposites are very stable materials without significant desorption of the biopolymer when they are treated with aqueous salt solutions for long periods of time. In this way, they act as active phases of electrochemical sensors for detection of ions (Figure 1.8). The particular nanostructuration of the biopolymer in the interlayer region drives the selective uptake of monovalent versus polyvalent anions, which has been applied in electrode arrays of electronic tongues [132]. 

Chitosan-clay bio-nanocomposites showing the ability to incorporate anionic species can be used to prepare functionalized biohybrids. An example is the uptake of anionic dyes such as fast green and naphthol yellow S which are low-toxicity... 

Fig. 1.10 SEM micrographs of chitosan-based bio-nanocomposites involving (A) sepiolite and (B) montmorillonite as the inorganic moiety.

Fig. 1.18 (A) Schematic representation of gelatin-perovskite bio-nanocomposite. (B) TEM image ofTBA-modified perovskite and (C) SEM image of this TBA-perovskite after assembly...

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