Improvement of surface bioactivity of poly(lactic acid) biopolymer by sandblasting with hydroxyapatite bioceramic
Abstract This study communicates a simple and effective method for modification of the surface of synthetic biopolymer poly(lactic acid) (PLA) with bioactive ceramic hydroxyapatite (HA) using a sandblasting technique. The sandblasting particles were bombarded onto the PLA, covering the surface quite evenly. The HA-sandblasted PLA showed good in vitro apatite forming ability in a simulated body fluid within a few days, which was rarely observed for pure PLA. Moreover, the HA-sandblasted PLA enhanced the initial cell adhesion and further proliferation, and up-regulated bone cell functions such as the alkaline phosphatase activity. This novel method of surface modification of the biopolymer with bioactive ceramic has the potential for use in developing bone bioactive implantable materials.
PURPOSE: A plasma etching method using a selective polymer deposition is to provide a high quality resolution and a good etching profile, by using a thin photoresist pattern as an etching mask. CONSTITUTION: An insulating layer on a wafer is plasma-etched for a predetermined interval of time by using a photoresist pattern(130) as a mask. A polymer layer(140) is formed by selectively evaporating polymer on the photoresist pattern. The insulating layer is plasma-etched by using the photoresist pattern and the polymer layer as a mask.