Biomimetic Artificial Nacre: Boron Nitride Nanosheets/Gelatin Nanocomposites for Biomedical Applications

Abstract

A bioinspired boron nitride nanosheet (BNNS)/gelatin nanocomposite consisting of hierarchically aligned layered BNNSs bonded with gelatin is fabricated by using electrostatic interactions between the oppositely charged functional groups on gelatin and the BNNSs. To enhance the self‐assembly and interfacial bond strength between these entities, the BNNSs are functionalized using hyperbranched polyglycerol. The 2D alignment of the BNNSs can be controlled by increasing the amount of BNNSs, or by a functionalization process, both of which result in transformation of the nanoscale structure from a randomly oriented to a brick‐and‐mortar structure. The mechanical properties of the resulting nanocomposite material, including the strength and modulus, are controlled by changing the composition of BNNSs and gelatin in the nanocomposite and by modifying the degree of alignment of the BNNSs in the material. This tuning of the mechanical properties yields a material whose performance resembles that of human cortical bone. In vitro cell viability experiments on the BNNSs/gelatin nanocomposite reveal that this artificial nacre supports adhesion, viability, and proliferation of adipose‐derived stem cells, all of which are essential for biomedical applications. Mechanical and biological testing of the material suggests applications of artificial nacre in biomedical fields and for tissue regeneration.