文摘
Micellar nanoparticles made of surfactants and polymers have attracted wide attention in thematerials and biomedical community for controlled drug delivery, molecular imaging, and sensing; however,their long-term stability remains a topic of intense study. Here we report a new class of robust, ultrafinesilica core-shell nanoparticles formed from silica cross-linked, individual block copolymer micelles.Compared with pure polymeric micelles, the main advantage of the new core-shell nanoparticles is thatthey have significantly improved stability and do not break down during dilution. We also studied the drugloading and release properties of the silica cross-linked micellar particles, and we found that the new core-shell nanoparticles have a slower release rate which allows the entrapped molecules to be slowly releasedover a much longer period of time under the same experimental conditions. A range of functional groupscan be easily incorporated through co-condensation with the silica matrix. The potential to deliver hydrophobicagents into cancer cells has been demonstrated. Because of their unique structures and properties, thesenovel core-shell nanoparticles could potentially provide a new nanomedicine platform for imaging, detection,and treatment, as well as novel colloidal particles and building blocks for mutlifunctional materials.