Ultrasmall MoS₂ Nanodots-Doped Biodegradable SiO₂ Nanoparticles for Clearable FL/CT/MSOT Imaging-Guided PTT/PDT Combination Tumor Therapy

Recently, we developed ultrasmall molybdenum disulfide (MoS2) quantum dots for computed tomography (CT) and multispectral optoacoustic tomography (MSOT) imaging-guided photothermal therapy (PTT). But, due to rapid body elimination and limited blood circulation time, the tumor uptake of the dots is low. In our study, this problem was solved via designing an amino-modified biodegradable nanomaterial based on MoS2 quantum-dots-doped disulfide-based SiO2 nanoparticles (denoted MoS2@ss-SiO2) for multimodal application. By integrating the MoS2 quantum dots into clearable SiO2 nanoparticles, this nanoplatform with an appropriate particle size can not only degrade and excrete in a reasonable period induced by redox responsiveness of glutathione but also exhibit a high tumor uptake due to the longer blood circulation time. Moreover, hyaluronic acid and chlorin e6 (Ce6) were adsorbed on the outer shell for tumor-targeting effect and photodynamic therapy, respectively. So, this biodegradable and clearable theranostic nanocomposite, which is applicable in integrated fluorescence/CT/MSOT imaging-guided combined photothermal therapy (PTT) and photodynamic therapy, is very promising in biomedical applications in the future.