Derivatives of Graphene Oxide as Potential Drug Carriers

Chemically functionalized graphene oxides could be used as novel drug carriers. Covalent alterations of graphene oxides lead to surface changes via formation of chemical bonding while non-covalent ones involve van der Waals forces, hydrogen bonding, and pi-pi stacking interactions. Covalent modifications appear to be superior as they can yield compounds with desired properties and carriers prepared by other methods are less stable. Synthesis of graphene oxide-iminodiacetic acid and graphene oxide-glycine involves nucleophilic substitution of graphene oxide nanoparticles with iminodiacetic acid or glycine. As the first step, iminodiacetic acid or glycine were transformed into iminodiacetic acid or glycine methyl ester hydrochlorides, respectively, for C-terminus protection. The obtained product, activated in situ, was then used to form amide bonds between graphene oxide and iminodiacetic acid or glycine.