Hybridized double-shell periodic mesoporous organosilica nanotheranostics for ultrasound imaging guided photothermal therapy

Hybridized periodic mesoporous organosilica (PMO) nanoparticles are expected to provide a multifunctional theranostic platform for precision medicine by combining the advantages of different organic and inorganic components. In this work, double-shell-structured PMO nanotheranostics composed of ethane- and thioether-bridged organosilica shells were synthesized. Gold colloids were generated in situ by the thioether groups on the inner shell. The obtained double-shell PMO@Au (DSPA) has uniform size, large surface areas, ordered mesochannels and photothermal conversion capability. After being encapsulated with perfluorohexacene (PFH), DSPA-PFH produced a strong ultrasound signal upon laser irradiation due to the phase transit of PFH during hyperthermia. DSPA-PFH showed enhanced photothermal therapeutic efficacy, great ultrasound contrast, and minimal toxicity both in vitro and in vivo. These results demonstrated the distribution of different organosilica could be delicately adjusted in hybridized PMO nanoparticles. Furthermore, it showed the potential of using hybridized PMO nanoparticles as a theranostic platform for biomedical applications by combining unique characteristics of different organosilica through rational design.