Microencapsulation process and product

Abstract

A composition comprising a core material, having a taste value and polymeric coating. The polymeric coating substantially surrounds the core material and comprises a cationic polymer and optionally an anionic polymer. The polymeric coating has a uniform thickness ranging from 2 μm to 20 μm. The composition provides release of a portion of the core material which is taste masked over a time period ranging from 0.5 minute to 2 minutes in the oral cavity and provides a modified-release of the remaining core material in a gastrointestinal tract.

We claim: 
     
         1 . A composition comprising:
 a core material having a taste value;   a polymeric coating substantially surrounding the core material, said polymeric coating comprising a cationic polymer and optionally an anionic polymer, wherein said polymeric coating has a uniform thickness ranging from 1 μm to 20 μm;   wherein said composition provides a controlled release of a portion of the core material which is taste masked over a time period ranging from 0.5 minute to 2 minutes in the oral cavity and provides modified-release of the remaining core material in a gastrointestinal tract.   
     
     
         2 . The composition of  claim 1 , wherein the composition has a microcapsule form. 
     
     
         3 . The composition of  claims 1  and  2 , wherein the polymeric coating is hydrophilic. 
     
     
         4 . The composition of  claims 1 - 3 , wherein said uniform thickness of the polymeric coating varies over a range from 0.2 μm to 2.0 μm. 
     
     
         5 . The composition of  claims 1 - 4 , wherein said polymer further comprises a crosslinking agent. 
     
     
         6 . The composition of  claims 1 - 5 , wherein the core material comprises an active pharmaceutical ingredient. 
     
     
         7 . The composition of  claim 6 , wherein said active pharmaceutical ingredient includes Acetaminophen, Ibuprofen, dexibuprofen lysinate, naproxen, loperamide, dimenhydrinate, doxylamine, dextromethorphan and chlorpheniramine. 
     
     
         8 . The composition of  claims 1 - 7 , wherein said cationic polymers are independently selected from the group consisting of: gelatin type A, gelatin type B, gelatin hydrolysates, gelatin succinylates, ovalbumin, serum albumin, casein, chitin, polyvinylamine, cellulose derivatives, or mixtures thereof. 
     
     
         9 . The composition of  claim 8 , wherein the cationic polymer is independently selected from the group consisting of: gelatin type A, gelatin type B, gelatin hydrolysates, gelatin succinylates and mixtures thereof. 
     
     
         10 . The composition of  claims 1 - 9 , wherein said anionic polymers are independently selected from the group consisting of: a polyphosphates, chitosan, linear silicones, gum arabic, sodium alginate, carrageenan, cellulose acetate phthalate, pectin, carboxymethylcellulose, ethylene maleic anhydride or mixtures thereof. 
     
     
         11 . The composition of  claim 1 - 10 , wherein the polyphosphates are a mixture of linear polyphosphates of varying chain lengths. 
     
     
         12 . The composition of  claim 11 , wherein the polyphosphate mixture is a medium chain polyphosphate and a long chain polyphosphate. 
     
     
         13 . The composition of  claims 1 - 12 , wherein
 the core material has a water solubility taste threshold and an associated pH of less than or equal to 6; and   wherein the polymeric coating has a pH value less than or equal to the associated pH of the water solubility taste threshold.   
     
     
         14 . The composition of  claim 13 , wherein the water solubility taste threshold ranges from 1×10 −4  mol/L to 1×10 −1  mol/L. 
     
     
         15 . The composition of  claims 1 - 12 , wherein
 the core material has a water solubility taste threshold and an associated pH of greater than or equal to 6; and   wherein the polymeric coating has a pH value less than or equal to the associated pH of the water solubility taste threshold.   
     
     
         16 . The composition of  claim 15 , wherein the water solubility taste threshold ranges from 1×10 −4  mol/L to 1×10 −1  mol/L. 
     
     
         17 . A pharmaceutical formulation comprising the composition according to  claims 1 - 17  and further comprising one or more pharmaceutically acceptable ingredient are independently selected from the group consisting of: excipients, binders, lubricants, disintegrating agents, sugar alcohols, colors, flavors and combinations thereof. 
     
     
         18 . The pharmaceutical formulation of  claim 17 , wherein said composition is compressible at compression pressure of up to 160 MPa and retains the composition's taste mask and modified-release properties.