細胞／植體金屬表面電化學性質研究

Electrochemical Behavior of Implant Metals Cultured with Cells

金屬植體（implant）表面的電化學性質與其生物相容性質息息相關。本研究利用電化學技術評估類造骨細胞（osteoblast-like cell）（U-2 OS）在植體金屬（拋光處理的Ti及Ti-6Al-4V合金）表面的成長過程（72小時）。利用電化學交流阻抗頻譜（electrochemical impedance spectroscopy, EIS）量測技術分析細胞成長過程中金屬表面極化電阻（polarization resistance, Rp）的變化，利用掃描式電子顯微鏡觀察不同時期細胞在金屬表面的成長形態。實驗結果顯示，Ti及Ti-6Al-4V合金表面經細胞附著後之Rp值均比未附著細胞的對照組試片高。Ti及Ti-6Al-4V合金表面的Rp值隨著細胞的成長（包括貼附、伸展及增殖階段）而漸增。細胞成長過程中，Ti及Ti-6Al-4V合金的Rp值均高於3.7 Mohm-cm2，而Ti的Rp值較Ti-6Al-4V合金高。本研究顯示，EIS量測技術可成功應用於監測細胞在金屬表面的成長過程。

The biocompatibility of metal implant is related to its surface electrochemical behavior. In this study, the electrochemical technique was used to monitor the growing process of osteoblastlike cells (U-2 OS) on implant metals (polished Ti and Ti-6Al-4V alloy) during 72 h incubation. Polarization resistance (Rp) of metals cultured with U-2 OS cells was measured by using electrochemical impedance spectroscopy (EIS) measurement technique. Surface morphology of cultured cells on metals was observed by using scanning electron microscope after different incubation periods. Results showed that the presence of cells on Ti and Ti-6Al-4V alloy led to an increase in Rp of metals. The Rp of Ti and Ti-6Al-4V alloy cultured with cells increased with the growth of cells, i.e. adhesion, spreading, and proliferation period. Regardless of the incubation period, the Rp values of Ti and Ti-6Al-4V alloy were higher than 3.7 Mohm-cm2, and Ti showed a higher Rp than Ti-6Al-4V alloy. In the present investigation, the EIS measurement technique was successfully applied to monitor the growing process of U-2 OS cells on Ti and Ti-6Al-4V alloy.