Multifunctional Core-Shell Cobalt Oxide @ Carbon Nanodot Hybrid Conjugates for Imaging and Targeting A549 Cells

The advent of research using drug-delivery vehicles with nanoparticles (NPs) in treating and diagnosing lung cancer has created a potential development in cancer therapeutics. Using certain NP-based compositions, specifically hybrid NPs, the cancer cells could be detected with enhanced fluorescence ability and treated using targeted drug release while minimizing adverse effects. A modified microwave-based synthesis approach was used in this study to synthesize spherical core-shell hybrid cobalt oxide carbon nanodot (Co₃O₄@CND) NPs of a smaller size of around 20 nm. Four different targeting ligands─folic acid, heparin, PEGylated silica (SiO₂), and transferrin─and the anticancer drug doxorubicin (DOX) were conjugated to the hybrid NPs, and their physicochemical characterizations were evaluated for their applications. The bioimaging, antioxidant, biocompatibility, cancer-targeting ability, and anticancerous specificity effect of the hybrid NPs were examined using A549 (lung cancer) cells and compared with CNDs, Co₃O₄ NPs, and the ligand-conjugated NPs. The Co₃O₄@CND NPs demonstrated high fluorescence from their synergistic properties, leading to a better bioimaging ability in human cells. The Co₃O₄@CND hybrid NP-transferrin-DOX composite targeted 50% of A549 cells with a much less adverse effect on EAhy926 (endothelial) cells at the same concentrations. Increased anticancer activity of the Co₃O₄@CNDs and improved biocompatibility were achieved via a receptor-mediated active targeting approach using specific ligands, proving the potential multifunctional applications such as bioimaging, antioxidant, and anticancer activity. After transferrin conjugation, the NP composite is more anticancerous to A549 and shows decreased toxicity to EAhy926 cells. The outcomes, while in the early stage, suggest that the Co₃O₄@CND hybrid NPs with ligand conjugation are a potential approach to the development of a multifunctional theranostic agent.