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Application of rapid cloud point extraction method for trace cobalt analysis coupled with spectrophotometric
Xiaodong Wen1, Lei He, Chunsheng Shi
1College of Pharmacy and Chemistry, Dali University, Dali, Yunnan 671000, China. wenxdong129@163.com
Summary
This study enhances spectrophotometer performance for detecting ultra-trace cobalt using rapidly synergistic cloud point extraction (RS-CPE). The improved method offers a low detection limit and high accuracy for cobalt analysis.
Area of Science:
- Analytical Chemistry
- Environmental Science
Background:
- Conventional spectrophotometry often lacks sensitivity for ultra-trace element analysis.
- Preconcentration techniques are crucial for improving detection limits in trace analysis.
Purpose of the Study:
- To enhance the analytical performance of spectrophotometry for ultra-trace cobalt determination.
- To couple a preconcentration method with spectrophotometric analysis for improved sensitivity.
Main Methods:
- Developed and optimized a rapidly synergistic cloud point extraction (RS-CPE) method for cobalt preconcentration.
- Coupled RS-CPE with spectrophotometric determination for cobalt analysis.
- Optimized factors influencing both RS-CPE and spectrophotometric measurements.
Main Results:
- Achieved a low limit of detection (LOD) of 0.6 μg/L for cobalt.
- Obtained a sensitivity enhancement factor of 23.
- Demonstrated high precision with a relative standard deviation (RSD) of 4.3% for 50 μg/L cobalt.
- Reported acceptable recoveries (93.8-105%) for spiked samples.
Conclusions:
- The developed RS-CPE coupled with spectrophotometry is a simple, rapid, and efficient method for ultra-trace cobalt determination.
- This approach significantly improves the analytical performance of conventional spectrophotometers.
- The method is suitable for accurate and sensitive analysis of cobalt in samples.
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