隨著科技發展，糖尿病患者日益攀升，因此糖尿病的預防與控制成為一個急需關注的議題。許多研究提出，控制糖化血色素的濃度可以預防或延緩糖尿病併發症產生，其最大的優勢不同於一般血糖值，容易受到藥物、運動、飲食等因素影響，常有相當大的起伏而造成誤判，糖化血色素之濃度為紅血球生命周期內的平均血糖濃度，較為準確可靠。
目前糖化血色素的量測技術受到檢測儀器成本高、操作複雜、不易攜帶等限制，因此研發成本低、設備小、簡單快速、可攜式的感測晶片為重要的研究議題。本篇論文整合指叉式電極及雙螺旋式電極，並利用交流電滲流可驅動奈米粒子的特性，設計新式環型指叉電極來改善糖化血色素在感測電極上的分佈均勻度及固定效率，進而提升感測的靈敏度，並縮短檢測所需的時間。在電極上利用硫吩硼酸修飾表面形成自組性單分子層，由於硫吩硼酸會與糖類反應產生二醇亞硼酸使糖化血色素固定在電極表面，而生物分子吸附在電極表面時會造成阻抗的變化，最後藉由電極加以電訊號直接量測電極間的電容變化，並比較附著前與附著後的阻抗，不同濃度的糖化血色素會產生不同比例的阻抗變化，成功檢測出濃度區間1~100 ng/µL之糖化血色素，便以此畫出糖化血色素之檢量線。

Glycated hemoglobin (HbA1c) is one of the most important diagnostic assays for the long-term mark of glycaemic control in diabetes. This study presents an affinity biosensor for HbA1c detection based on impedance measurement, the detection process of which is label-free requiring no additional reagents, and features low cost and low sample volume. The ring-shaped interdigital electrodes (RSIDEs) are designed to promote the distribution uniformity and immobilization efficiency of HbA1c, and are further employed to characterize the impedance change and identify various concentrations of HbA1c. The self-assembled monolayer (SAM) of thiophene-3-boronic acid (T3BA) is provided to modify the gold electrode surface. Afterwards, the esterification reaction between HbA1c and T3BA produces a relative change of electrical property on the electrode surface. The RSIDEs with SAM of T3BA exhibits a wide range from 100 to 10 ng/µL producing an approximate logarithmic decrease of impedance, a low detection limit of 1 ng/µL, a good selectivity and short-term stability for HbA1c determination. The remarkable advantages, including miniaturization and low-cost, have the potential of point-care diagnostics for portable sensor development.

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