Biodegradable oxidized cellulose esters

• US 7,662,801 B2
• Filed: 12/13/2005
• Issued: 02/16/2010
• Est. Priority Date: 12/29/2000
• Status: Expired due to Fees

• Current Assignee: University of Iowa Research Foundation
• Original Assignee: University of Iowa Research Foundation
• Inventors: Kumar, Vijay, Dang, Yang
• Primary Examiner(s): Jiang; Shaojia Anna
• Assistant Examiner(s): White; Everett
• Application Number:
  US11/301,900
• Publication Number:
  US 20060093672A1
• Time in Patent Office: 1,526 Days
• Field of Search: 536/63, 536/64, 536/67, 536/68, 536/69, 536/32, 514/54
• US Class Current: 514/54
• CPC Class Codes: C08B 15/00 Preparation of other cellulose derivatives or modified cellulose , e.g. complexes
• CPC Class Codes: C08B 3/00 Preparation of cellulose esters of organic acids rendering cellulose suitable for esterification C08B1/02

Abstract

The present invention relates to the preparation of a series of oxidized cellulose esters suitable for use as a drug carrier in the development of biodegradable controlled and/or sustained release pharmaceutical, agricultural, and veterinary compositions, such as films, compacts, microspheres, and pellets. The esters are prepared by acylation of oxidized cellulose having at least 3% carboxyl groups. The resulting oxidized cellulose esters are soluble in aqueous alkaline solutions, water, and a variety of organic solvents.

Claims

1. A monolithic transparent film comprising a biodegradable oxidized cellulose ester, said oxidized cellulose ester having the following general formula I or II, wherein said film is modified from an oxidized cellulose having a carboxyl content from 3% to 25%:

2. A biodegradable coating composition comprising a biodegradable oxidized cellulose ester, said oxidized cellulose ester having the following general formula I or II, wherein said coating is modified from an oxidized cellulose having a carboxyl content from 3% to 25%:

3. A product selected from the group consisting of a pharmaceutical formulation, an agricultural product, and a veterinary composition, said product comprising at least one active ingredient and a biodegradable, oxidized cellulose ester, said oxidized cellulose ester having the following general formula I or II, wherein said product is modified from an oxidized cellulose having a carboxyl content from 3% to 25%: