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Updated: Jun 28, 2026
07:49
Characterizing Lewis Pairs Using Titration Coupled with In Situ Infrared Spectroscopy
Published on: February 20, 2020
Ion-exchanger phase spectrophotometry for trace cobalt.
T Nakashima1, K Yoshimura, H Waki
1Department of Chemistry, Faculty of Science, Fukuoka University, Nanakuma, Jonan-ku, Fukuoka 814-01, Japan.
Talanta
|July 1, 1990
Summary
A new ion-exchanger phase spectrophotometric method using Nitroso-R salt allows for sensitive cobalt(II) determination in seawater. This technique significantly enhances detection limits for trace metal analysis.
Area of Science:
- Analytical Chemistry
- Environmental Chemistry
Background:
- Accurate determination of trace metals like cobalt is crucial for understanding marine ecosystems.
- Conventional spectrophotometric methods often lack the sensitivity required for detecting cobalt at environmentally relevant levels in seawater.
Purpose of the Study:
- To develop a highly sensitive method for determining cobalt(II) in seawater.
- To improve upon existing analytical techniques for trace metal analysis in marine samples.
Main Methods:
- Development of an ion-exchanger phase spectrophotometric method.
- Utilizing disodium 1-nitroso-2-naphthol-3,6-disulphonate (Nitroso-R salt) as a chelating agent.
- Application of the method for cobalt(II) determination at trace levels.
Main Results:
- The developed method enables the determination of cobalt(II) at concentrations as low as 0.1 µg/L.
- The sensitivity of this new method is approximately 1000 times greater than conventional spectrophotometry.
- Successful application in analyzing cobalt levels in seawater samples.
Conclusions:
- The ion-exchanger phase spectrophotometric method with Nitroso-R salt offers a significant advancement in the sensitive detection of cobalt(II) in seawater.
- This method provides a valuable tool for environmental monitoring and research requiring precise trace metal quantification.
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