仿地質熱熔射噴塗法製備多孔性鍶鎂混摻氫氧基磷灰石陶瓷材料

Abstract

本實驗以氫氧化鈣與磷酸為起始原料，利用共沉降法製備氫氧基磷灰石，並且利用氫氧化鍶與氫氧化鎂來進行摻雜。將製備出的漿料在1000 ℃下進行鍛燒，並且利用XPS、XRD等方式測量摻雜比例。發現，鍶的摻雜也與文獻中相同C軸方向生長，利用拉曼光譜分析與傅立葉轉換紅外光譜來確認材料內部官能基與摻雜後的變化情況，並用掃描式電子顯微鏡觀察噴塗後的表面型態與摻雜後的晶體變化，發現鍶的含量越多晶型越往針狀發展，再利用XPS來確認摻雜比例，發現確實與預估的趨勢相同。而熱噴塗方面，我們將製備的氫氧基磷灰石，利用聚乙烯醇在 17 : 1 的重量百分比下進行2天的混合球磨，將顆粒黏大後，依照需要的大小進行研磨過篩，此步驟大大提升了粉體流動性。接著調控噴塗的速率、距離與送粉孔徑，尋找最佳噴塗參數，依序噴製鈦圓板、304不銹鋼螺絲與市售牙根。最後進行MTT與ALP等生物細胞測試，發現了鍶的摻雜有助於細胞成長，但過量會具有毒性。尋找到最佳鍶濃度後，再共摻雜鎂，發現混摻5 %鍶離子和5 %鎂離子的氫氧基磷灰石噴塗至鈦圓板基材上可得最佳生物活性及生物相容性。最後，探討溼式噴塗，發現注入水後，塗層表面因為水氣衝出，造成許多裂紋與孔洞。由斷面SEM觀察得知，同樣噴塗條件下溼式噴塗的堆積較為蓬鬆，而形成的多孔性塗層影響細胞活性，在MTT與ALP上11天後，均有較顯著的成長，之後透過螢光染色顯影，可以更清楚觀察到溼式噴塗對於細胞成長的影響。

Hydroxyapatite had been to know a calcium phosphate of formula Ca10(PO4)6(OH)2 which is one of the Bisphosphonates (BPs) to consider as the most active inhibitors for bone degradation [1, 2]. In this study, we reported the fabrication of strontium and magnesium doped with hydroxyapatite by thermal spray technology coating on commercially pure Ti-disc substrates. First, HA powder was doped with 0.5, 1, 5 and 10 mole% of Sr (Sr-HA). Secondly, we co-doped 0.5, 1, 5, 10 mole% Mg (SrMg-HA) by precipitation method, heating to treat at 1000 ℃ for 4 h and then used for thermal spray coating. Samples were confirmed to be phase pure by XRD and functional group of HA was observed by ATR-FTIR and Raman. In vitro cell–materials interactions using human embryonic palatal mesenchymal cells(HEPM) showed better cell attachment and proliferation on 1Sr-HA coatings compared to HA or other Sr-HA coatings. However, presence of 5Sr-HA coatings in the coating was better than others on the expression of alkaline phosphatase (ALP). Finally, the 5Sr5Mg-HA coatings had the best compromise for HEPM promotion and ALP activity. Our study indicated that the fabricated SrMg-HA might be a potential candidate as bioactive bone-regeneration and materials of implant coating