Preparation of a bonelike apatite–polymer fiber composite using a simple biomimetic process

Abstract

A bonelike apatite-polymer fiber composite may be useful as an implant material to replace bone, the enthesis of a tendon, and the joint part of a ligament. We treated an ethylene-vinyl alcohol copolymer (EVOH) plate and knitted EVOH fibers with an oxygen plasma to produce oxygen-containing functional groups on their surfaces. The plasma-treated samples were alternately dipped in alcoholic calcium and phosphate ion solutions three times to deposit apatite precursors onto their surfaces. The surface-modified samples formed a dense and uniform bonelike surface apatite layer after immersion for 24 h in a simulated body fluid with ion concentrations approximately equal to those of human blood plasma. The adhesive strength between the apatite layer and the sample's surface increased with increasing power density of the oxygen plasma. The apatite-EVOH fiber composite obtained by our process has similarities to natural bone in that apatite crystals are deposited on organic polymer fibers. The resulting composite would possess osteoconductivity due to the apatite phase. With proper polymer selection and optimized synthesis techniques, a composite could be made that would have bonelike mechanical properties. Hence, the present surface modification and coating process would be a promising route to obtain new implant materials with bonelike mechanical properties and osteoconductivity.

Preliminary in vivo study of apatite and laminin‐apatite composite layers on polymeric percutaneous implants

“…[15][16][17][18] This coating process is carried out by alternately dipping a polymer specimen in calcium and phosphate solutions three times and then immersing it in calcium phosphate solution (CP solution) supersaturated with HA for more than 3 hours. As a result of the dipping treatment, nanoparticulates of amorphous calcium phosphate (ACP), which is a precursor of HA, are deposited on the specimen surface.…”

Fabrication of DNA-antibody–apatite composite layers for cell-targeted gene transfer

“…This feature is advantageous in tissue engineering applications because apatite-based composite layers can be coated on various types of base materials including bioresorbable poly(ε-caprolactone) [30,31] and poly(l-lactide) [42]. These base materials can take forms of not only tabular substrates but three-dimensional porous bodies [30,31,43], fibers [44] and sponges [45], which are suitable as scaffold structures. Thus-coated composite layers provide biocompatible surface to support cell adhesion and growth [13,[15][16][17], and can stimulate the cell effectively via the area-specific gene transfer on their surfaces [17,46].…”

Development of apatite-based composites by a biomimetic process for biomedical applications

“…2(a)), 18), 19) fibers (Fig. 2(b)), 22) and sponges ( Fig. 2(c)) 57) as well as twodimensional tabular plates.…”

“…The strength of adhesion between the polymer and the apatite layer formed on its surface can be improved by regulating the pretreatment conditions. 21), 22) In the case of PLL, its strength of adhesion to the bonelike apatite layer increases up to approximately 6 MPa by optimizing plasma power density in the oxygen plasma pretreatment (Fig. 3).…”