Mesoporous silica nanoparticles combined with MoS2 and FITC for fluorescence imaging and photothermal therapy of cancer cells

The construction of effective and safe theranostics was very important to realize tumor diagnosis and treatment simultaneously. Photothermal therapy had obtained great attention due to its remarkable capability of both cancer treatment and biosecurity. Molybdenum disulfide (MoS2) nanoflakes have shown excellent photothermal conversion efficiency, which were explored to photothermal therapy. However, MoS2 nanoflakes would decrease or quench the intensity of fluorescence when the MoS2 nanoflakes directly incorporated with fluorescence dyes to construct bioimaging theranostic systems. In this work, MoS2 nanoflakes embedded into MSNs to construct photothermal nanomaterials, which realized the nanoparticle size controllable. Fluorescein isothiocyanate (FITC) conjugated with mesoporous silica nanoparticles via amide bonds for bioimaging. It was more stable than physical absorption. As expected, the as-prepared FITC–MoS2 MSNs possessed photothermal effect, fluorescence stability and photostability. FITC–MoS2 MSNs were quickly taken up by HepG2 cells. Meanwhile, the HepG2 cells could be efficiently ablated under the 808 nm near-infrared laser irradiation. These results proved that we successfully constructed multifunctional MSNs for tumor theranostics. It also provided a potentially common nanoplatform for theranostic of biomedical applications.