Transferrin-conjugated nanodiamond as an intracellular transporter of chemotherapeutic drug and targeting therapy for cancer cells

Aim: PEGylated fluorescent nanodiamond (FND) conjugated with Tf (FND-PEG-Tf) was investigated for targeted drug delivery. Materials & methods: Human hepatoma (HepG2) and normal (L-02) cell lines were used to investigate the difference in cellular uptake of FND-PEG-Tf and its loading drug system. Nanoparticle uptake was evaluated by flow cytometry and laser scanning confocal microscopy. Results: FNDPEG-Tf showed highly specific TfR-mediated uptake by HepG2 cells, relative to negative controls (L-02 cell), which was a strong correlation among TfR density on the cell surface. The mechanism of TfR-mediated uptake was attested by free Tf with Fe3+ as a competitive agent. The difference in cell viability between L-02 and HepG2 cells treated with doxorubicin hydrochloride (DOX) nanoparticles (FND-PEG-Tf-DOX) can be explained by FND-PEG-Tf, which can target drug delivery to cancer cells. Conclusion: FND-PEG-Tf can potentially be utilized in targeted cancer cell imaging and effective drug delivery for cancer therapy.