本研究的主要目的是利用白金電極對白金二價錯離子的獨特催化性質，藉由微電極微小化具低侵入性的優點發展抗癌藥物-順鉑的電化學偵測平台。 在過去並未有人探討在人體生理條件下順鉑的電化學行為，實驗第一部分將以一系列循環伏安法探討各種條件下包括酸鹼度、工作電極材質、氯離子濃度、迴轉電壓等，對順鉑的電化學特性的影響，由上述實驗結果推論順鉑在白金電極上的反應途徑為軸向氧化(Axial oxidation pathway)，為增進系統重複偵測的再現性，於量測過程需要經過電位處理活化電極表面。故本實驗採用脈衝電壓以活化電極搭配一直流電壓進行電極的前處理程序。在最佳化處理後，連續偵測順鉑八次的再現性由未處理前的44.3%降低為1.2%，顯示電位處理具有高度的穩定性作用。 經電位處理最佳化後，電化學實驗選擇以微差脈衝伏安法 (Differential Pulse Voltammetry)進行抗癌藥物順鉑的偵測，在溶液環境為0.05 M磷酸緩衝溶液，pH7.4內含0.103 M的氯化鈉條件下，脈衝振幅大小50 mV、脈衝時間75 msec、脈衝周期為200 msec、取樣時間為脈衝結束前16.7 msec的操作條件下，其偵測線性範圍從5 μM 至200 μM (R=0.999)，靈敏度為3.383×10-6A/M，本系統的偵測極限為460 nM (S/N=3)，對於20 μM cisplatin重複操作的相對標準偏差為1.78 % (n=20)。 A novel method for the fast detection of cisplatin by platinum microelectrode has been developed. The typical electrochemical behavior of cisplatin in different parameters including pH, concentration of chloride ion, material of working electrode and its surface condition has been investingated by cyclic voltammetry. Subsequently, cisplatin has measured by differential pulse voltammetry (DPV) using a microelectrode with effective radius of 13.6μm. This method involves a potential pretreated process to renew the activity of electrode surface. In contrast to a series of measurements without the pretreatment process, the relative standard deviation (n = 8) could be reducing from 44.3% to 1.2% compared with original process. After careful optimization, the analytical performance of current microelectrode was evaluation in the buffer solution of 0.05M, phosphate buffer pH7.4 containing 0.103M sodium chloride. The linear range of cisplatin is between 5μM to 200μM (R =0.999) with sensitivity of 3.383×10-6A/M. The estimated detection limit of this scheme is about 460 nM (S/N=3) and the relative standard deviation of twenty respective detection measurement of 20 μM cisplatin is 1.78%.
