Biodegradable Stealth Polymeric Particles Fabricated Using The Macromonomer Approach By Free Radical Dispersion Polymerization

Abstract

The present invention is directed to a crosslinked or non-crosslinked polymer particle, wherein the crosslinked polymer particle comprises a copolymer of poly(alkylene glycol-graft-lactate) that is crosslinked by at least one hydrolysable monomer. Another embodiment of the present invention is a polymer particle comprising a crosslinked polymer particle that is a product of starting materials comprising (a) a hydrophilic monomer, (b) a hydrophobic monomer, and (c) a hydrolysable crosslinking agent. Another embodiment of the present invention is a polymer particle comprising, a crosslinked copolymer comprising structures represented by Formulas (I), (II), and (III), where Formulas (I), (II) and (III) are defined in the specification. Yet other embodiments of the present invention include a method of preparing a methacrylate terminated macromonomer, a method of preparing a crosslinking agent, and a method of preparing a therapeutic agent loaded nanosphere by dispersion polymerization.

What is claimed is: 
     
         1 . A method of preparing a methacrylate terminated macromonomer, the method comprising the steps of:
 (i) reacting L-lactide, an initiator and a catalyst under vacuum for 10 minutes   (ii) flushing the reaction vessel with nitrogen for 24 to 38 hours at a temperature of 120-240° C.   (iii) extracting the resulting polymer from an organic solution.   
     
     
         2 . The method of  claim 1 , wherein the initiator is selected from the group consisting of hydroxymethacrylate (HEMA) or hydroxylpropylmethacrylamide (HPMA). 
     
     
         3 . The method of  claim 1 , wherein the amount of L-lactide is 0.0418 moles. 
     
     
         4 . The method of  claim 1 , wherein the amount of initiator is 0.00738 mole.