Hollow silica nanospheres and methods of making same

Abstract

The disclosure provide hollow nanospheres and methods of making and using the same. The methods and compositions of the disclosure are useful for drug delivery and gene transfer.

What is claimed is: 
     
         1 . A hollow silica nanoparticle for imaging tissue, comprising:
 a shell structure including silica and having a hollow interior, wherein the shell structure is porous; and   a biocompatible coating on an outer surface of the shell structure.   
     
     
         2 . The hollow silica nanoparticle of  claim 1 , wherein the shell structure includes a spherical shape. 
     
     
         3 . The hollow silica nanoparticle of  claim 1 , wherein the hollow silica nanoparticle includes a diameter in a range of 10 nm to 1000 nm. 
     
     
         4 . The hollow silica nanoparticle of  claim 1 , wherein the shell structure includes a diameter in a range of 40 nm to 500 nm. 
     
     
         5 . The hollow silica nanoparticle of  claim 1 , wherein the shell structure includes a thickness in a range of 3 nm to 5 nm. 
     
     
         6 . The hollow silica nanoparticle of  claim 1 , wherein the shell structure is formed of a uniform silica material layer having a plurality of pores distributed over the shell structure. 
     
     
         7 . The hollow silica nanoparticle of  claim 6 , wherein the shell structure is formed by deposition of a silica compound on a functionalized template particle that is removed to create the hollow interior within the uniform silica material layer, wherein the uniform silica material layer is able to withstand collapsing upon itself upon removal of the template particle. 
     
     
         8 . The hollow silica nanoparticle of  claim 1 , wherein the biocompatible coating includes phosphonate polyethylene glycol (PPEG). 
     
     
         9 . The hollow silica nanoparticle of  claim 1 , further comprising:
 a fluorescent dye coupled to the shell structure.   
     
     
         10 . The hollow silica nanoparticle of  claim 9 , wherein the hollow silica nanoparticle is configured to locate at a tissue in a region of a living subject's body and to produce a detectable optical signal responsive to light directed at the tissue based on fluorescence of the fluorescent dye of the hollow silica nanoparticle. 
     
     
         11 . The hollow silica nanoparticle of  claim 1 , wherein the hollow silica nanoparticle is configured to locate at a tissue in a region of a living subject's body and to produce a detectable signal responsive to ultrasonic energy directed at the tissue based on a material property of the hollow silica nanoparticle. 
     
     
         12 . The hollow silica nanoparticle of  claim 1 , wherein the shell structure further includes a magnetic material. 
     
     
         13 . The hollow silica nanoparticle of  claim 12 , wherein the hollow silica nanoparticle is configured as an X-ray imaging agent or a magnetic contrast agent in imaging a tissue of an organism. 
     
     
         14 . A nanoparticle device for ultrasound imaging, comprising:
 a cluster of monodisperse silica nanoparticles, each comprising a silica shell structure having a hollow interior, wherein the shell structure is porous, and a biocompatible coating on an outer surface of the silica shell structure; and   a binder disposed about the monodisperse silica nanoparticles to form a capsule.   
     
     
         15 . The nanoparticle device of  claim 14 , wherein the binder includes gelatin. 
     
     
         16 . The nanoparticle device of  claim 14 , wherein the biocompatible coating includes phosphonate polyethylene glycol (PPEG). 
     
     
         17 . The nanoparticle device of  claim 14 , wherein the silica shell structure includes a spherical shape. 
     
     
         18 . The nanoparticle device of  claim 14 , wherein each of the monodisperse silica nanoparticles includes a diameter in a range of 10 nm to 1000 nm. 
     
     
         19 . The nanoparticle device of  claim 14 , wherein the silica shell structure further includes a magnetic material, and wherein the cluster of monodisperse silica nanoparticles are configured to provide an X-ray imaging agent or a magnetic contrast agent when imaging the tissue of the living subject.