Patent ID: 7927629

Claim:
A method of producing filamentous polymeric nanocarrier particles that encapsulate a biologically active protein, comprising: (a) forming a primary emulsion using a freeze-thaw cycle of (i) an amphiphilic diblock copolymer, which has a molecular weight of about 10,000 to about 100,000 Da and comprises a hydrophobic polymer block conjugated to a hydrophilic polymer block, wherein said amphiphilic diblock copolymer comprises greater than 81% to about 95% by weight of said hydrophobic polymer block; and (ii) a biologically active protein having a molecular weight of up to or equal to about 300,000 Da; (b) forming a secondary emulsion from said primary emulsion; and (c) recovering filamentous polymeric nanocarrier particles from the secondary emulsion, wherein said filamentous particles have a diameter of less than 70 nm and a length of from about 1 to about 50 microns, and encapsulate the biologically active protein and protect it from proteolysis.