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Fabrication and characterization of porous hydroxyapatite scaffolds with PMMA addition using tertiary-butyl alcohol based freeze casting method

삼차부틸알코올 기반 동결주조 공정을 이용한 PMMA 첨가 다공질 수산화아파타이트 지지체의 제조 및 특성 평가

  • Received : 2017.08.11
  • Accepted : 2017.09.22
  • Published : 2017.10.31

Abstract

In order to prepare porous scaffolds capable of pore control, PMMA powder serving as a pore-forming agent was added to HA powder to synthesize a slurry containing TBA as a solvent. And then, porous HA scaffolds where pillarshaped pore channels interconnected with each other were fabricated by freeze-casting and sintering. The crystal structure of the HA scaffolds according to the addition amount of PMMA powder was measured by XRD and the surface and inner cross section of the scaffolds were analyzed through SEM. It was found that removal of PMMA during sintering affects the internal structure of the scaffolds and the crystallinity of the HA powder. Furthermore, through evaluating the physical and mechanical properties of the scaffolds, it was confirmed that the porosity, pore size and compressive strength can be controlled by controlling the addition amount of the pore-forming agent. It was also found that the HA scaffolds produced in this study were similar in structure and properties to the natural cancellous bone. This suggests that porous HA scaffolds with PMMA can be used as an alternative to autogenous bone for tissue engineering as an artificial bone scaffold.

기공 제어가 가능한 다공질 인공 지지체를 제조하기 위해 HA 분말에 기공형성제 역할을 하는 PMMA 분말을 첨가하여 TBA를 용매로 한 slurry를 합성한 후 동결주조와 소결을 거쳐 주상형 기공채널이 상호 연결되어 있는 다공질 HA 지지체를 제조하였다. PMMA 분말의 첨가량에 따른 HA 지지체의 결정구조는 XRD로 측정하였고 SEM을 통하여 지지체의 표면 및 내부 단면을 관찰하였는데, 소결과정에서 PMMA의 탈지가 지지체의 내부구조와 HA 분말의 결정성에 영향을 미치는 것으로 결과가 나타났다. 또한 지지체의 물리적 및 기계적 특성을 평가하여 기공형성제의 첨가량을 조절함으로써 기공률 및 기공 크기와 압축 강도의 제어가 가능하였다. 본 연구 결과, HA 지지체가 천연 해면골과 구조 및 특성이 유사하였으며 이를 통해 PMMA 첨가 다공질 HA 지지체가 조직공학용 인공 골지지체로서 자가골을 대체하여 사용이 가능한 것으로 판단된다.

Keywords

References

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