Core stabilized microcapsules, method of their preparation and uses thereof

Abstract

The present invention provides core-stabilized microcapsules, wherein said core comprises at least one active agent encapsulated within a metal oxide shell, processes for their preparations, comparisons comprising them and uses thereof.

What is claimed is: 
     
         1 . Microcapsules comprising a core encapsulated by a metal oxide shell, wherein said core has a viscosity of between about 300 cP to about 1,000,000 cP and comprises at least one active agent and at least one phase changing material; wherein the thickness of said metal oxide shell is in the range 0.1-10 micron; and wherein said shell is obtained from (a) metal oxide nanoparticles, and (b) a hydrolyzed and polymerized sol gel precursor. 
     
     
         2 . The microcapsules according to  claim 1 , wherein said at least one phase changing material is selected from natural or synthetic paraffin, aliphatic alcohols, fatty acids or any combination thereof. 
     
     
         3 . The microcapsule according to  claim 1 , wherein said at least one active agent is selected form a pharmaceutical agent, a cosmetical agent and an agrochemical agent. 
     
     
         4 . The microcapsules according to  claim 1 , wherein said core comprises a dermatological agent. 
     
     
         5 . The microcapsules of  claim 1 , wherein said core comprises a dermatological agent selected from anti-fungal agents, anti-bacterial agents, anti-inflammatory agents, anti-pruritic agents, anti-psoriatic agent, anti-acne agents, anti-rosacea agents, and any combinations thereof. 
     
     
         6 . The microcapsules of  claim 5 , wherein said anti-acne agent is selected from benzoyl peroxide, retinoid, and mixtures thereof. 
     
     
         7 . The microcapsules according to  claim 1 , capable of being stable for a period of between about 2 weeks to about 2 years at room temperature. 
     
     
         8 . A composition comprising microcapsules comprising a core encapsulated by a metal oxide shell, wherein said core has a viscosity of between about 300 cP to about 1,000,000 cP and comprises at least one active agent and at least one phase changing material; wherein the thickness of said metal oxide shell is in the range 0.1-10 micron; and wherein said shell is obtained from (a) metal oxide nanoparticles, and (b) a hydrolyzed and polymerized sol gel precursor. 
     
     
         9 . A method for treating a surface condition in a subject in need thereof, said method comprising topically administering to said subject a composition according to  claim 8 . 
     
     
         10 . The method of  claim 9 , wherein said surface is skin or mucosal membrane. 
     
     
         11 . The method of  claim 9 , wherein said surface condition is a skin disease, disorder or condition selected from acne, infection, inflammation, pruritis, psoriasis, seborrhea, contact dermatitis, rosacea, and a combination thereof.