Nacre-inspired composite gels for biomedical applications
Nacre (or mother of pearl) is found in the inner shell layer of certain molluscs & has a complex hierarchical structure made of hard (CaCO3) and soft (proteins) components. Layers of hexagonal plates of aragonite, which is a crystalline form of CaCO3 are held together by a matrix of proteins. Incorporation of the soft protein in between the hard aragonite plates imparts superior mechanical strength to nacre, compared to pure aragonite. This ingenious combination of materials result in remarkable properties, such as, resistance against fracture, high pressure absorption, prevention of crack propagation, and being incredibly light weight.
Inspired by these features, we have developed robust, flexible materials with self-adaptive and self-healing properties. Polymer hydrogels were incorporated with functional nanoparticles to produce composites with unique physicochemical and mechanical properties. 3D printing was utilized as an effective technique to combine the nanoparticles with polymer gels, in hexagonal well-matrix structures, in order to combine “hard” and “soft” components. The materials have customizable physical and mechanical properties and 3D printing allows a wide range of design dimensions for making nanoparticle-gel composites. These novel materials displayed enhanced capabilities in mechanical strength, self-adaptation to environmental stresses and in self-healing ability and together with their biocompatibility, allow for a myriad of highly useful biomedical applications.