- 學位論文
植入式葡萄糖感測電極於細胞間質替代液之特性探討
Performance studies of implantable glucose electrode in ISF surrogate
摘要
本研究課題針對吾人所研製之微型葡萄糖感測電極作探討，除了研究中所設計之微型電極外，尚使用市售的白金電極(CPE)、市售電化學分析儀(CECA)以及自製之射頻(RF)無線傳輸感測系統。首先運用交聯反應將葡萄糖氧化酶固定於CPE表面，最外層覆蓋生物相容性之保護薄膜，藉由CECA探討葡萄糖感測電極之最佳操作電位與校正曲線，並觀察葡萄糖感測電極於細胞間質替代液(血清)環境下之穩定性。最後將葡萄糖感測電極製程，轉移至微型三極式電極並驗證感測葡萄糖之能力，整合微型葡萄糖感測電極與無線感測系統，以探討整合系統之精確度。由實驗結果得知，葡萄糖氧化酶與戊二醛之交聯方式於CPE表面，具有較佳之穩定性。在保護薄膜方面，熱塑性聚氨酯覆蓋於葡萄糖感測電極表面，於血清模擬體內環境中具有分辨葡萄糖濃度變異之能力，在操作電位為+ 0.5 V時，具有最佳反應電流與排除干擾物質之能力。於磷酸鹽緩衝溶液環境下，具有寬廣之量測範圍，葡萄糖濃度0~30 mM之校正曲線具有高線性度(R2 = 0.996)；於血清環境中，葡萄糖濃度為0~22 mM之校正曲線也具有高線性度(R2 = 0.984)。於模擬體溫37 oC之血清環境之下，長達3週實驗中葡萄糖感測電極之穩定性仍保持100 %。微型葡萄糖電極在CECA量測結果中，證實具有良好線性度(R2 > 0.997)。將微型葡萄糖感測電極搭配射頻(RF)無線傳輸感測裝置，量測不同濃度之葡萄糖溶液與CECA量測結果誤差小於1 %。由實驗結果證實，吾人研製之微型葡萄糖感測電極，將有潛力應用於植入式感測之範疇。
並列摘要
This course evaluated an in-house developed miniature glucose sensing electrode. In addition to the mini-electrode, the evaluation studies include a commercial platinum electrode (CPE), a commercial electrochemical analyzer (CECA), and an in-house built radio-frequency (RF) based wireless sensing system. The experiment of glucose oxidase immobilized on the CPE with the cross-linking technique was performed by the CECA first. Next, the outermost layer of the electrode was covered by membranes with biocompatibility. This enzyme modified CPE was studied to search the optimal operating potential and the linear range of glucose concentration. In addition, the stability of the modified CPE in surrogate fluid (serum) was studies. The study results indicate that the CPE using glutaraldehyde to crosslink glucose oxidase demonstrates the superior stability. The thermoplastic polyurethane serving as the semi-permeable membrane of the electrode is most capable of differentiating glucose level fluctuation in serum. The operating potential of 0.5-volt performs optimal signal response and suppresses interfering substances most. The linear response range of glucose concentration 0~30 mM in PBS is R2 = 0.996. In the serum, the linearity of glucose concentration 0~22 mM is R2 = 0.984. When the CPE stored in the serum controlled at the temperature of 37 oC, the stability remained 100% for 3 weeks. The same preparation was applied to the developed mini-electrode, whose performance by the CECA showed good linearity (R2 > 0.997) in the glucose concentration of 0~24 mM. The glucose oxidase modified mini-electrode was evaluated by the developed RF based sensing system and the CECA. The glucose detection performance in the range of 0~21 mM (R2 = 0.999) between the two sensing systems was less than 1%. In conclusion, the developed mini-glucose sensor has potential to be used in implantable applications.