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Reverse flow injection analysis of complexing agents and its application to estimation of complexing capacity
N Teshima1, H Itabashi, T Kawashima
1Laboratory of Analytical Chemistry, Department of Chemistry, University of Tsukuba, Tsukuba 305, Japan.
Talanta
|January 1, 1993
Summary
A new method uses a copper reaction with neocuproine to detect trace complexing agents. This technique enables rapid measurement of complexing capacity for various metal ions.
Area of Science:
- Analytical Chemistry
- Environmental Chemistry
Background:
- The redox reaction between copper(II) and iron(II) is slow without catalysts.
- Neocuproine facilitates this reaction, forming a copper(I)-neocuproine complex.
- Complexing agents significantly accelerate this reaction.
Purpose of the Study:
- To develop a rapid analytical method for determining trace complexing agents.
- To establish a new procedure for measuring the complexing capacity of metal ions.
Main Methods:
- Utilizing a copper(II)-iron(II)-neocuproine redox reaction.
- Employing a reverse flow injection analysis (r-FIA) system.
- Monitoring the increase in absorbance at 454 nm.
Main Results:
- Trace complexing agents at the 10(-6)M level were determined with high throughput (120 samples/hr).
- A novel method for measuring complexing capacity of Al(III), Cu(II), Zn(II), Cd(II), and Pb(II) was established.
- The r-FIA system demonstrated efficient and rapid analysis.
Conclusions:
- The developed r-FIA method is effective for sensitive determination of complexing agents.
- This technique provides a fast and reliable approach for assessing metal ion complexing capacity.
- The method offers a valuable tool for environmental and chemical analysis.
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