Loadable polymeric particles for therapeutic and/or diagnostic applications and methods of preparing and using the same

Abstract

Particles are provided for use in therapeutic and/or diagnostic procedures. The particles include poly[bis(trifluoroethoxy) phosphazene] and/or a derivatives thereof which may be present throughout the particles or within an outer coating of the particles. The particles can also include a core having a hydrogel formed from an acrylic-based polymer. Barium sulfate may also be provided to the core of the particles as a coating or absorbed within the core of the particles. The particles can be used to minimize blood flow to mammalian tissues by occluding at least a portion of a blood vessel of the mammal, or to deliver an active agent to a localized area within a body of a mammal by contacting a localized area with at least one of the particles. Further, the particles are useful in sustained release formulations including active agent(s) for oral administration, as tracer particles for injection into the bloodstream of a mammal or for use in enhanced ultrasound imaging. The particles may include agents for increasing density for achieving useful buoyancy levels in suspension.

1 . A method for minimizing agglomeration and/or aggregation of particles formed from acrylic-based polymers, comprising providing barium sulfate to the particles. 
     
     
         2 . The method according to  claim 1 , wherein the particles comprise a core and an outer coating, and the core is infused with the barium sulfate. 
     
     
         3 . The method according to  claim 1 , wherein the particles comprise a core and an outer coating, and the barium sulfate is applied to an outer surface of the core. 
     
     
         4 . The method according to  claim 1 , wherein the step of providing barium sulfate to the particles comprises applying an aminosilane adhesion promoter to the particle and applying by adhesion the barium sulfate to the particle. 
     
     
         5 . The method according to  claim 1 , wherein the particles comprise an outer coating of poly [bis (trifluoroethoxy) phosphazene] and/or a derivative thereof. 
     
     
         6 . The method according to  claim 2 , wherein the core comprises a hydrogel formed from an acrylic-based polymer. 
     
     
         7 . The method according to  claim 1 , wherein the particle comprises a contrast agent selected from the group consisting of barium sulfate, tantalum compounds, gadolinium compounds and iodine-containing compounds. 
     
     
         8 . The method according to  claim 1 , wherein the particle is porous and non-degradable. 
     
     
         9 . The method according to  claim 1 , wherein the particle further comprises at least one active agent configured to release an effective amount of the active agent during a treatment procedure. 
     
     
         10 . A method of enhanced ultrasound imaging comprising administering to an ultrasound subject at least one hollow microcapsule comprising poly [bis (trifluoroethoxy) phosphazene] and/or a derivative thereof to an area of the ultrasound subject, and imaging the area of the ultrasound subject using ultrasound. 
     
     
         11 . The method according to  claim 10 , wherein the at least one hollow microcapsule comprises a shell defining an inner cavity, the inner cavity being at least about 20% of the volume of the entire microcapsule. 
     
     
         12 . The method according to  claim 10 , wherein the at least one hollow microcapsule comprises a shell defining an inner cavity, the inner cavity being at least about 30% of the volume of the entire microcapsule. 
     
     
         13 . The method according to  claim 10 , wherein the at least one hollow microcapsule comprises a shell defining an inner cavity, the inner cavity being at least about 40% of the volume of the entire microcapsule. 
     
     
         14 . The method according to  claim 10 , wherein the at least one hollow microcapsule comprises a shell defining an inner cavity, the inner cavity being at least about 50% of the volume of the entire microcapsule. 
     
     
         15 . The method according to  claim 10 , wherein the at least one hollow microcapsule comprises a shell defining an inner cavity, the inner cavity being at least about 80% of the volume of the entire microcapsule. 
     
     
         16 . The method according to  claim 10 , wherein the at least one hollow microcapsule comprises a shell defining an inner cavity, the inner cavity being at least about 90% of the volume of the entire microcapsule.