Method of controlling the pH in the vicinity of biodegradable im

Details Method of controlling the pH in the vicinity of biodegradable im Method of controlling the pH in the vicinity of biodegradable im

1994-12-21

1998-04-21

Prebilic, Paul

Prosthesis (i.e., artificial body members), parts thereof, or ai

Implantable prosthesis

623 16, 606 76, 523113, 523115, 424423, A61F 202

Patent

active

057413290

ABSTRACT:
The invention discloses pH-controlling devices that comprise a biodegradable polymer and a pH-controlling substance, particularly an alkaline, acidic or buffering agent. 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 also 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.

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