氯離子為人血清細胞外含量最高的陰離子，負責人體機能的維持，若長期處於正常值範圍外，會因細胞滲透壓失衡導致腎功能異常。一般醫院的血液檢測檢測流程相當耗時，因此開發一套可自我檢測的氯離子傳感器，不但能大幅減少檢測耗時及花費，同時也方便隨時追蹤自身身體狀況。
微流體電化學傳感器結合了電化學檢測方法及微流體系統的優點，有著快速、高靈敏度、高準確度的優勢，同時也僅需微量的樣品和反應試劑，是生醫傳感器的開發趨勢。本研究介紹了改性電極的製程，該電極可應用於病人血清氯離子的實際檢測。主要使用一般市售絲網印刷電極，在電極表面以電解沈積的方式使其吸附銀粒子，再透過施加時變電壓，使銀粒子與檢體中的氯離子產生反應，藉由偵測其反應過程的電流大小，回推氯離子濃度。
接著利用參數優化的方式穩定改性電極的製程及降低檢測誤差，結合壓克力晶片進行水溶液及病人血清的檢測，於20例水溶液和40例洗腎病人血清中，與實際濃度值的相關係數分別為0.9989及0.9915，顯示以改性電極晶片的檢測方式，可實際應用於真實檢體的檢測，具有相當高的準確性及穩定度。

Chloride ion is the highest anion content in the extracellular human serum. It mainly maintain proper water distribution, osmotic pressure and electrochemical neutrality of human cells. The rapid detection of chloride ion allows patients to aware of symptoms early and treat or control the disease.
Microfluidic electrochemical biosensor combines the advantages of electrochemical detection methods and microfluidic system. It has the advantages of rapid detection, high sensitivity, high accuracy, low cost, and low sample volume required. In this study, the fabrication of modified electrodes for human chloride ion detection were introduced. By using electrodeposition method, we deposited the silver particles on the surface of commercial screen-printed carbon electrodes (SPCE). The presence of chloride ion in the solution and human serum cause a voltammetry signal which is related to the oxidation of silver to silver chloride. The signal correlates linearly with the concentration of chloride ion from 1 mM to 120 mM in solution, 1 mM to 60 mM in human serum, respectively.
In order to verify the silver particles modified electrode biosensor, we detected 20 solutions of different chloride ion concentration and 40 patients’ serum samples. The results of detection compared with real values and National Cheng Kung University Hospital results. The correlation coefficients are 0.9989 in solution, 0.9915 in patients’ serum which show that the modified electrodes can be applied on solution and serum chloride ion detection.

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