The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 17, 1998
Filed:
Aug. 02, 1996
Edith Mathiowitz, Brookline, MA (US);
Claudy JP. Mullon, Cambridge, MA (US);
Abraham J Domb, Brookline, MA (US);
Robert S Langer, Somerville, MA (US);
Massachusetts Institute of Technology, Cambridge, MA (US);
Abstract
A method for preparation of biodegradable polymeric drug delivery devices using relatively low temperatures and non-aqueous solutions which is particularly useful with polyanhydrides, thermolabile drugs, and in forming multi-layered devices. In a first embodiment, the polymer is dissolved in a volatile organic solvent, the drug is dispersed or dissolved in the polymer solution, the mixture is suspended in an organic oil, and the organic solvent is extracted into the oil, creating microspheres. The preferred polymers are polyanhydrides since they are biodegradable and have been proven to be useful in vivo. In a second embodiment, the polymer is dissolved in organic solvent with or without the drug, and the mixture is suspended in glycerol. The suspension is frozen and the organic solvent slowly evaporated. Using these embodiments, alone or in combination with other methods including the 'hot melt' technique, multi-walled microspheres having each wall degrading at a different rate or containing different drugs can be manufactured.