Green synthesized cobalt doped graphene quantum dots derived from Boswellia serrata for dual ligand targeted bioimaging and delivery of exemestane.
Harde Minal T MT, Ingle Rahul R, Dhamal Sakshi S, Deshmukh Prashant P et al.
Major objective of hydrothermal method is to achieve the synthesis of Cobalt doped Graphene quantum dots (Co-GQDs) using natural precursor (Boswellia serrata gum resin). The Co-GQDs were surface engineered with folic acid (FA) and hyaluronic acid (HA) to enable dual targeting module (Co-GQDFH), followed by loading of the anticancer drug Exemestane (EXE@Co-GQDs). The nanosized, crystallite structure with high luminescence intensity was maintained after functionalization and drug loading process was assessed from preliminary physicochemical analysis. The EXE@Co-GQDFH forms complex via passive loading approach and achieves and entrapment efficiency of 68.58%. The in-vitro drug release study shows extended release of EXE from the surface functionalized Co-GQDFH for 24 h and releases (~ 88%) maximum encapsulated drug. The dose dependent toxicity was observed for EXE@Co-GQDFH (49.5 µg/ml) on MCF-7 cell breast cancer cell types while IC50 value was comparable to 5-Fluorouracil. The fluorescent Co-GQD shows high bioimaging and cellular uptake efficiency in MCF-7 cells. The surface conjugation with FA and HA on Co-GQDs shows enhanced activity with zone of inhibition was found to be 25 mm while the Co-GQD shows 20 mm suggest conjugation improved the antimicrobial effect. Radical scavenging activity was also demonstrated, with Co-GQDs showing 77.92% and EXE@Co-GQDs was 59.02% DPPH inhibition. These results suggest that surface-engineered Co-GQDs offer a multidentate nanoplatform for targeted delivery, imaging, and therapy in breast cancer applications.