摘要
本研究以循環伏安法探討水相中銅-胺基酸錯合物的電化學性質，我們發現銅-胺基酸錯合物呈現一個電子轉移且為半可逆氧化還原反應。整個電極反應如下：

第一式代表雙配位銅錯合物的還原與其逆反應(亦即氧化反應)，第二、六式代表銅與其配位基的脫離與結合的反應，第三式代表一價銅離子的自身氧化還原反應。第四、五式代表一價銅與零價銅的氧化反應。由改變pH值、銅濃度與胺基酸濃度來觀察以雙配位與單配位物種為多數時的電化學反應，佐以理論的推算，確認銅-胺基酸錯合物為雙配位時，在還原前後的配位基個數相同。
銅-胺基酸錯合物的半波電位值與所鍵結配位基的種類相關。非均相電子傳遞速率常數為一個固定常數並不會隨著掃描速率的快慢而變化，在9種銅-胺基酸錯合物中，其非均相電子傳遞速率常數的範圍約在3.5×10-3 ~ 4×10-4 cm s-1 之間，最大與最小值的差值約10倍左右，差異並不大。由於一價銅量子產率為雙配位錯合物經過光分解為一價銅離子過程的反應速率，而k0值為雙配位錯合物經過還原反應變為一價銅錯合物的反應速率。因此兩者之間還存在著一價銅錯合物繼續分解速率的影響，所以會造成兩者之間有不簡單的排序關係。

Abstract
A detailed investigation on the electrochemical reduction of copper/amino acid complexes has been carried out using cyclic voltammetry with platinum microdisk electrode in aqueous solution containing 0.1M KCl as the supporting electrolyte. The stage of the first electron attachment is quasi-reversible reaction. The mechanism of the electrode process is following:

We investigated the effects of nine different amino acids, that is α-alanine, asparagine, glutamine, glycine, isoleucine, proline, serine, threonine, valine on the rate constant of heterogeneous electron transfer, k0, of the quasi-reversible reaction of Cu(II)L2 calculated by the theory developed by Nicholson.The mean values of k0 with nine different amino acids were between 3.5×10-3 ~ 4×10-4 cm s-1 with a standard deviation of 45%.The order of k0 dose not have simple correlation with that of Cu(I) quantum yield at 313nm.

Key words:
Copper/amino acid complexes; quasi-reversible reaction; rate constant; heterogeneous electron transfer; quantum yield.

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