Polymer Shells

Abstract

The present invention relates to a method for the preparation of polymer shells, preferably composed of cellulose or hemicellulose, comprising the steps of dissolving the polymer component in a first solvent, preferably an organic solvent and precipitating the polymer component by contacting the first solution with a second solvent, which second solvent has a polar character, and in which second solvent the polymer component is essentially insoluble, thereby obtaining polymer shells. Moreover, the invention refers to the polymer shells as such, having permeable and responsive properties, as well as various applications comprising such polymer shells within the fields of drug delivery, separation techniques, and inter alia filling material.

1 .- 27 . (canceled) 
     
     
         28 . A cellulose shell, comprising a shell wall having a thickness from 100 nm to 2 mm and encasing a space comprising a gas, wherein the cellulose shell has an outer diameter between 10 μm and 10 mm. 
     
     
         29 . The cellulose shell of  claim 28 , wherein the outer diameter of the shell is from 10 μm to 5 mm. 
     
     
         30 . The cellulose shell of  claim 28 , wherein the outer diameter of the shell is from 10 μm to 2 mm. 
     
     
         31 . The cellulose shell of  claim 28 , wherein the outer diameter of the shell is from 10 μm to 1 mm. 
     
     
         32 . The cellulose shell of  claim 28 , wherein the shell wall has a thickness from 0.5 μm to 500 μm. 
     
     
         33 . The cellulose shell of  claim 28 , wherein the shell wall has a thickness from 2 μm to 30 μm. 
     
     
         34 . The cellulose shell of  claim 28 , further comprising a molecule comprising xyloglucan attached to the shell. 
     
     
         35 . A method for preparing the cellulose shell of  claim 28 , comprising:
 (a) dissolving cellulose in a solvent comprising at least one organic solvent to produce a solution of step (a);   (b) dissolving a core-forming substance in the solution of step (a) wherein the core-forming substance comprises at least one gas, by feeding said gas into the solution of step (a) or by pressurizing the solution of step (a) with said gas, to produce a solution of step (b); and   (c) precipitating the cellulose and forming cores by transferring the solution of step (b) into a second solvent having a polar index of at least 2.4, thereby obtaining cellulose shells formed around said cores when the solution of step (b) is entering the second solution.   
     
     
         36 . The method of  claim 35 , wherein the second solvent is water. 
     
     
         37 . A drug delivery device comprising the cellulose shell of  claim 28 . 
     
     
         38 . A chromatographic separation device comprising the cellulose shell of  claim 28 , wherein the shell is a solid phase component. 
     
     
         39 . A filling material comprising the cellulose shells of  claim 28 , wherein the type of filling material is selected from the group consisting of packaging material, joint filling material, and weathering material. 
     
     
         40 . A method for chromatographic separation, comprising using the cellulose shell of  claim 28  as a solid phase component.