Development of A Redox Speciation Method of Copper(I/II) in Environmental Water Samples by Solid Phase Extraction / Inductively Coupled Plasma Mass Spectrometry
We developed to a Cu(I)/Cu(II) speciation method of Cu(I)/Cu(II) using solid phase extraction (SPE) followed by inductively coupled plasma mass spectrometry (ICP-MS). In order to separate Cu(I) from Cu(II), Cu(I) and Cu(II) were complexed with bathocuproinedisulfonic acid (BCS) and ethylenediaminetetraacetate (EDTA), respectively. The Cu(I)-BCS showed a high affinity to hydrophobic solid phases such as C18, C8, tC2. On the other hand, Cu(II)-EDTA was not adsorbed on these hydrophobic solid phases. The Cu(I)-BCS adsorbed in these SPEs could be quantitatively separated by a methanol aqueous solution. When we applied this speciation method to a rain water sample, the recoveries of Cu(I) and Cu(II) were higher than 90%.