Mitochondria-targeting photosensitizer-encapsulated amorphous nanocage as a bimodal reagent for drug delivery and biodiagnose in vitro.

The use of ceramic nano-carriers containing anti-cancer drugs for targeted delivery that span both fundamental and applied research has attracted the interest of the scientific community. In this paper, a hydrophobic photodynamic therapy drug, hypocrellin A (HA), was successfully encapsulated in water-soluble amorphous silica nanocage (HANC) by an improved sol-gel method. These nanocages are of ultrasmall size, highly monodispersed, stable in aqueous suspension, and retain the optical properties of HA. Moreover, these nanocages can be effectively delivered, subsequently taken up by cancer cells and finally targeted to mitochondria. In addition, incubation time dependent photodynamic efficacy difference between HANC and HA was investigated for the first time. Especially, the nanocages, owning extremely high stable fluorescence comparing with free HA, also have potentials as efficient probes for optical biodiagnose in vitro. All these properties of HANC could possibly make it especially promising to be used as a bimodal reagent for photodynamic therapy and biodiagnose.