含鋅之磷灰石／幾丁聚醣複合材料之性質及降解行為研究

Properties and Biodegradation Behavior of zinc-containing Apatite/Chitosan Composites

鄭人華(Jen-Hua Cheng) ； 丁信智(Shinn-Jyh Ding)

《中山醫學雜誌》 17卷2期 (2006/12) Pp. 201-210

https://doi.org/10.30096/CSMJ.200612.0005

摘要

In the past several years, hydroxyapatite (HA) ceramics have been extensively used as bone graft substitutes because of their osteoconductivity. Zinc promotes proliferation and differentiation of osteoblast cells and acts as a stimulator of bone growth. Naturally polymeric chitosan has many good biological properties including biodegradation. This makes chitosan useful in biomedical applications such as micropheres, membranes, and scaffolds. We prepared Zn-containing apatite/chitosan composite, which is similar to chemical composition of bone tissue, using a sol-gel route and freeze-drying method. X-ray diffraction patterns show that apatite phases can be obtained at 50000 for control condition. For those in which precursor solution with pH 9 were used, lower temperatures (300℃) sufficed. The tensile strength of monolithic apatite derived from the sol-gel processing at pH 9 (5.3 MPa) wassignificantly higher (P＜0.05) than that of samples without pH adjustment (3.8 MPa). We did not find that adding ZnO significantly affected strength value, though oriented growth of the HA phase on the (002) plane was enhanced. Incorporation of chitosan into bioceramic bulks did not affect strength value. Tensile strength decreased rapidly by 40%~50% (P＜0.05), after immersion in Hank's solution for 3 days, after which strength stabilized. In conclusion, by adjusting the precursor solution to a pH 9, the temperature needed for apatite synthesis can be reduced to 300℃, resulting in a higher initial tensile strength.

關鍵字

溶膠凝膠法 ； 氫氧基磷灰石 ； 幾丁聚醣 ； 鋅

並列摘要

In the past several years, hydroxyapatite (HA) ceramics have been extensively used as bone graft substitutes because of their osteoconductivity. Zinc promotes proliferation and differentiation of osteoblast cells and acts as a stimulator of bone growth. Naturally polymeric chitosan has many good biological properties including biodegradation. This makes chitosan useful in biomedical applications such as micropheres, membranes, and scaffolds. We prepared Zn-containing apatite/chitosan composite, which is similar to chemical composition of bone tissue, using a sol-gel route and freeze-drying method. X-ray diffraction patterns show that apatite phases can be obtained at 50000 for control condition. For those in which precursor solution with pH 9 were used, lower temperatures (300℃) sufficed. The tensile strength of monolithic apatite derived from the sol-gel processing at pH 9 (5.3 MPa) wassignificantly higher (P＜0.05) than that of samples without pH adjustment (3.8 MPa). We did not find that adding ZnO significantly affected strength value, though oriented growth of the HA phase on the (002) plane was enhanced. Incorporation of chitosan into bioceramic bulks did not affect strength value. Tensile strength decreased rapidly by 40%~50% (P＜0.05), after immersion in Hank's solution for 3 days, after which strength stabilized. In conclusion, by adjusting the precursor solution to a pH 9, the temperature needed for apatite synthesis can be reduced to 300℃, resulting in a higher initial tensile strength.

並列關鍵字

sol gel ； hydroxyapatite ； chitosan ； zinc