Molybdenum disulfide/carbon nanocomposite with enhanced photothermal effect for doxorubicin delivery

In this work, three different samples of molybdenum disulfide (MoS2) nanoflakes, carbon nanoparticles and molybdenum disulfide/carbon (MoS2/C) nanocomposite were synthesized by one step hydrothermal method. The structural and optical properties of the samples were characterized by X-ray diffraction, transmission electron microscopy, energy-dispersive X-ray spectroscopy mapping, Raman, Fourier transform infrared, and Ultraviolet–visible spectroscopies. Photothermal experiment was also performed for these three samples after 10 min laser irradiation (808 nm, 1 W/cm2 power density) for 600 s. The photothermal results of samples indicated that the effect of the carbon content in nanocomposite has produced higher heat in MoS2/C sample than other samples. Then, in order to load drug, a potent anti-cancer drug doxorubicin (DOX) was loaded in MoS2/C-PEG up to 21% and the release of drug was evaluated by irradiation of near infrared (NIR) light. In the NIR irradiation, the amount of DOX released in pH 5 from nanocomposite was higher than pH 7.4. The drug release was found to enhance with NIR laser irradiation, which shows that the composites respond by pH or NIR irradiation for DOX release, so the release process could be controllable. The results of MTT assay showed that carbon nanoparticles, MoS2, and MoS2/C samples possess negligible cytotoxicity without irradiation NIR laser. Using NIR irradiation, the relative viabilities of Hela cells decreased when the concentration of samples increased. For DOX-loaded MoS2/C-PEG, results revealed that by increasing DOX loading the cell viability decreases especially under the NIR irradiation.