Copper complexing capacity as an indicator for the evaluation of water quality

开发并发表了测定河水中可溶性铜（II）络合物的不稳定性的方法（Anal.Sci.，8，571（1992））。该方法基于只有通过铜（II）络合物解离形成的铜（II）离子吸附到chelex柱的现象。络合物的不稳定性定义为铜离子的相对吸附速率。本年度利用上述方法对吉柳江的环境特征进行了调查。除不稳定性外，还测定了铜络合容量（CuCC）、pH值、总有机碳、氨基酸等。总之，CuCC可提供形成相对较强的铜（II）络合物的配体的信息，而相对较弱的天然配体的行为可通过不稳定性测定进行分析。此外，我们发现环境中存在的配体大致分为几类：天然来源的配体和源自人类活动的配体（Bull.Chem.Soc.Jpn.，66，2104（1993））。我们的进一步研究导致开发了一种新的天然沃茨中铜（II）形态分析方法，其中Cu（II）-TTA的萃取被认为是主反应，Cu（II）和天然配体之间的副反应系数被确定为Cu（II）被上述配体络合的程度的量度（Anal.Sci.，贡献）。

A method of determining the lability of soluble copper(II)complex in river water was developed and published(Anal.Sci., 8,571(1992)). This method based on a phenomenon that only copper(II)ion formed via dissociation of a copper(II)complex adsorbs to the chelex column. Lability of the complex is defined as the relative rate of adsorption of copper(II)ion.By using the above method, environmental feature of the Kiryu river has been investigated thi year. Items measured other than lability are as follows : copper complexing capacity(CuCC), pH, total organic carbon, amino acids.In conclusion, CuCC was found to give information on a ligand which forms a relatively strong copper(II)-complex, while the behavior of a relatively weak natural ligand could be analyzed through lability measurement. In addition we found that environmentally occurring ligands are roughly derived into categories : ligands of natural origin and the ones derived from human activities(Bull. Chem.Soc.Jpn., 66,2104(1993)).Our further investigation leads to the development of a new method of speciation of copper(II)in natural waters in which the extraction of Cu(II)-TTA is regarded as a main reaction and a side reaction coefficient between Cu(II) and a natural ligand is determined as a measure of the degree of complexation of Cu(II) by the above ligand(Anal.Sci., in contribution).