Even though many members from the broad family of carbon nanostructures have been known to us for decades, and despite their promising potential in biology and medicine, there is still a long way ahead to reach the goal of using them in real applications. The cause of such a gap still lies in the persistent drawbacks of insolubility, processability difficulties, poor consistency of macroscopic assemblies and surface inertness of carbon nanostructures. However, solely their direct chemical derivatization might not solve the problem right away. New processing elements need to come into play, but this also twists the whole picture, as the toxicity and performance profiles become more complex. We herein analyse the potential of natural polysaccharides (with a particular focus on cellulose) towards hybrid materials and structures for biomedical purposes. The role that these biopolymers acquire when interfacing with carbon nanostructures goes far beyond a mere dispersing effect, but instead creates unprecedented synergies leading to hydrogels, aerogels, films or fibres with high biocompatibility and bioactivity. In this chapter, the history of carbon nanostructures and natural polysaccharides in the field of biomedical applications will be respectively reviewed, to subsequently go into detail of specific hybrids made with the most relevant biopolymers (namely cellulose, chitin, chitosan and alginate) with extraordinary prospects in biomedicine.

In the last 20sh years the Carbon Nanostructures’ family grew and attract the attention of many researchers working in different fields. Many efforts in the studies of functionalization have been done, especially struggling with the necessity of an easy way to manipulate these structures. Solubility and orthogonal multiple functionalization are the main goals to be achieved when these materials have to be used for biological applications, as oligonucleotides vector, potential antiviral derivatives, or gene expression modulators. In this communication, an overview of the recent achievements will be presented. Figure 1

Among the various carbon nanostructures, the graphene quantum dots represent an emerging 0D platform with very interesting properties for biological application. More specifically they are properly water-soluble, they can be decorated exploiting different chemical approaches and they possess intrinsic characteristics of fluorescence. Herein, we report a new top-down strategy to prepare these structures, that has been recently explored and allows an almost quantitative conversion of the carbon source, and some preliminary biological results.