In vivo tracking and biosafety of fluorescent graphene-cyclodextrin nanomaterials on zebrafish embryos

The combination of cyclodextrins (CD) with graphene-based nanomaterials (GBN) has been widely investigated to obtain graphene/cyclodextrin nanomaterials (GCD) endowed with unique relationships with biomolecules and/or living cells. However, their development in nanomedicine is still confined in the laboratory arena due to the lack of in vivo studies and safety data. Here, we report the synthesis and physicochemical properties of a new fluorescent graphene platform obtained by supramolecular assembly of cyclodextrin-functionalized graphene (GCD) and adamantanyl-rhodamine derivative (AdaRhod-2). The safety issues of GCD were assessed by in vitro cell culture and in vivo by a zebrafish embryo toxicity test (ZFET) to evaluate possible toxicity and pathological lesions of zebrafish (ZF) exposed to GCD@AdaRhod-2 at two selected concentrations 4 mg/L and 80 mg/L. GCD@AdaRhod-2 showed a reduced potential risk with respect to other GBN with a survival rate percentage more than 80% for both investigated concentrations. Finally, the fate of GCD@AdaRhod-2 during ZF embryo development was monitored by confocal microscopy images.