第二型糖尿病，又稱為成人型糖尿病、肥胖型糖尿病或非胰島素型糖尿病，是一種慢性疾病，影響全球超過三億的人口。雖然糖尿病無法治癒，但維持血糖濃度在正常範圍之內以避免併發症的發生則是可以做到的。葡萄糖與糖化血紅素是目前診斷糖尿病之重要指標。糖化血紅素代表過去2-3個月之平均血糖濃度。因此，糖化血紅素相較於快速波動的葡萄糖是更能作為診斷糖尿病的長期生物指標。現今，葡萄糖感測器已廣泛使用在糖尿病的診斷上，但居家型糖化血紅素感測器仍未商品化。
本研究之目的在開發一電極材料，應用在糖化血紅素之目標分子糖化纈胺酸之感測上，期待所設計之感測器能夠符合糖尿病病患之臨床診斷標準。以自製的玻璃碳膠電極(GCPE)作為工作電極，應用在電化學式糖化纈胺酸之感測上，於pH 7.4的磷酸鹽緩衝溶液中進行電化學測試。實驗結果顯示，糖化纈胺酸濃度與感測電流呈一線性關係，其線性偵測範圍在0至1 mM (0-0.358μg/dL)，其相關系數的平方為0.999，而靈敏度為167.5 μA/mM cm2，最小偵測極限為0.05 mM (0.018μg/dL)。
在新型電流式感測系統中，可以額外添加二茂鐵硼酸作為媒介分子在0.1V電位下進行糖化纈胺酸感測，因為由於二茂鐵硼酸能與雙醇分子形成錯合物並具有極佳的氧化還原電化學性質，所以，二茂鐵硼酸分子可以作為傳遞的媒介，藉由亞鐵/鐵離子的氧化還原，促使硼酸基團與糖化纈胺酸形成錯合物。在糖化纈胺酸生物感測器中，利用GCPE作為工作電極在3 mM的二茂鐵硼酸溶液中針對目標分子進行感測，結果顯示偵測範圍為0.5-4 mM (0.19-1.43μg/dL)，最小偵測極限為0.5 mM，應答時間為10秒。

Type-2 diabetes, also known as adult-onset diabetes, obesity-related diabetes or noninsulin-dependent diabetes mellitus, is a common chronic disease affecting more than 300 million people globally. Although incurable, the condition can be managed by maintaining blood glucose at a normal level. This is important to avoid serious complications. Glucose and glycosylated hemoglobin (HbA1c) are presently the important diagnostic targets. The relative amount of HbA1c reflects the average blood glucose concentration during the past 2-3 months; it is therefore able to serve as a long-term diagnostic marker, rather than the rapidly fluctuating glucose level. Currently, glucose sensors are routinely used for the diagnosis of the condition; however, an electrochemical HbA1c sensing system has not yet been commercialized in homecare.
An electrode material for sensing fructosyl valine (Fru-Val), a component of HbA1c, has been developed as a potential route towards the determination of physiological HbA1c levels in diabetic patients. A bare glassy carbon paste electrode (GCPE) was fabricated as the working electrode for sensing Fru-Val electrochemically in phosphate buffer (pH 7.4). A linear relationship between Fru-Val concentration and the sensing current was shown. The square correlation coefficient (R2) and the sensitivity of this biosensor were 0.999 and 167.5 μA/mM cm2, respectively. The minimum detection limit of the GCPE for Fru-Val was less than 0.05 mM.
A new diagnostic system, incorporating an amperometric method, for detecting Fru-Val (at +0.1 V vs. Ag/AgCl), using ferrocene boronic acid (FcBA) as a mediator is presented here. FcBA can form complex with diols, and has easily detectable redox properties. The boronic acid group in FcBA mediates complexation, while the FeⅡ/FeⅢ couple serves as a transducer. The Fru-Val biosensor using the GCPE as the working electrode in 3 mM FcBA solution could measure the target analyte (Fru-Val) in the 0.5 to 4 mM concentration range. The minimum detection limit was less than 0.5 mM for Fru-Val. The response time was 10 s.

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