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:
May. 23, 2000
Filed:
Jun. 01, 1995
C Mauli Agrawal, San Antonio, TX (US);
Kyriacos A Athanasiou, San Antonio, TX (US);
Board of Regents, University of Texas System, Austin, TX (US);
Abstract
The invention discloses pH-controlling devices that comprise a biodegradable polymer and a pH-controlling substance, particularly an alkaline, acidic or buffering agents. By way of example, such alkaline agents include calcium carbonate and sodium bicarbonate. Methods of preparing such devices are also described. Methods for enhancing biocompatibility of an implantable device are also provided, as neutralizing alkaline materials are released at a rate that offsets changes in pH typically observed as polymers degrade to various acidic or alkaline by-products. By way of example, biodegradable polymers include PLA, PGA, polycaprolactone, copolymers thereof, or mixtures thereof. A new technique is disclosed to increase the surface porosity of porous implants which have a tendency to form relatively impermeable coverings. This technique entails the use of mechanical means to remove at least part of said covering, thus increasing the implant's surface porosity and permeability.