Boron nitride has structural characteristics similar to carbon 2D materials (graphene and its derivatives) and its layered structure has been exploited to form different nanostructures such as nanohorns, nanotubes, nanoparticles and nanosheets. Unlike graphene and other carbon based 2D materials, boron nitride has a higher chemical stability. Owing to these properties, boron nitride has been used in different applications as a filler, lubricant and as a protective coating. Boron nitride has also been applied in the biomedical field to some extent, but far less than other 2D carbon materials. This review explores the potential of boron nitride for biomedical applications where the focus is on boron nitride biocompatibility in vivo and in vitro, its applicability as a coating material/composite and its anti-bacterial properties. Geometry, material processing and the type of biological analysis appear to be relevant parameters in assessing boron nitride bio-compatibility. Engineering of both these variables and the coating would open the door for some applications in the medical field for boron nitride, such as drug delivery, imaging and cell stimulation.

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Even if the carbon nanotubes (CNTs) and their derivatives are commonly used as reinforcing phase in composite materials, also in commercial products, their tendency to agglomerate generally determines a scarce dispersion, thus not maximizing the effect due to the second phase. In this article, a perfect dispersion of highly entangled nanotubes was achieved by using a very simple approach: exploiting the dispersing effect of a low‐cost polymer, polyvinyl butyral (PVB), coupled with standard ultrasound sonication. Several dispersion approaches were tested in order to develop a consistent and widely applicable dispersion protocol. The tape casting technology was subsequently used to produce 100 to 300 μm thick PVB‐matrix composite tapes, reinforced by multiwall CNTs dispersed according to the optimized protocol. Their mechanical properties were evaluated, and a simple model was used to demonstrate that the effective dispersion of CNTs is the key to obtain significantly improved properties.

Microbial colonization to biomedical surfaces and biofilm formation is one of the key challenges in the medical field. Recalcitrant biofilms on such surfaces cause serious infections which are difficult to treat using antimicrobial agents, due to their complex structure. Early detection of microbial colonization and monitoring of biofilm growth could turn the tide by providing timely guidance for treatment or replacement of biomedical devices. Hence, there is a need for sensors, which could generate rapid signals upon bacterial colonization. In this study, we developed a simple prototype sensor based on pristine, non-functionalized graphene. The detection principle is a change in electrical resistance of graphene upon exposure to bacterial cells. Without functionalization with specific receptors, such sensors cannot be expected to be selective to certain bacteria. However, we demonstrated that two different bacterial species can be detected and differentiated by our sensor due to their different growth dynamics, adherence pattern, density of adhered bacteria and microcolonies formation. These distinct behaviors of tested bacteria depicted distinguishable pattern of resistance change, resistance versus gate voltage plot and hysteresis effect. This sensor is simple to fabricate, can easily be miniaturized, and can be effective in cases when precise identification of species is not needed.