Nanoparticles can be used to integrate more than one kind of imaging or therapeutic function, which makes them promising multi-functional platforms for both diagnosis and therapy. Remarkable progress has been achieved in developing nanoplatforms for early cancer diagnosis or therapy, but the integration of two or more strategies in one system is still at its tentative stage and has become a particular challenge in bionanomedicine.
Now, Zhenxin Wang and co-authors have developed a facile methodology to construct a multifunctional theranostic nanoplatform that gathers five functions, upconversion luminescence imaging (UCL), T1-weighted magnetic resonance imaging (MRI), X-ray computed tomography imaging (CT), photothermal therapy (PTT), and chemotherapy, into one single nanocomposite. The nanocomposites were prepared by directly coating bioinspired polydopamine (PDA) shell on hydrophobic upconversion nanoparticles (UCNPs) via a microemulsion approach, which were then modified with polyethylene glycol (PEG) for improving their stability in physiological conditions.
The UCNP core was employed to provide the tri-modal imaging of UCL, MRI and CT. The PEGylated PDA shell exhibited strong photothermal effect and loading capacity for an aromatic anticancer drug like doxorubicin (DOX), which was further used for chemo-photothermal synergistic therapy. When combined with 808 nm NIR laser irradiation, the nanocomposites showed great synergistic interaction between PTT and the enhanced chemotherapy, resulting in completely eradicated mouse-bearing tumor without regrowth. Furthermore, the authors believe that their proposed strategy is highly simple and versatile, and can be easily extended to prepare other types of hydrophobic nanoparticle@PDA nanocomposites for biomedical applications. The expect that their research will pave a straightforward route to develop NIR-absorbing organic-inorganic nanocomposite-based multifunctional theranostic agents for imaging-guided chemo-photothermal synergistic therapy of cancer.