Sensitivity Enhancement in Uranium Determination by UV-Visible Spectroscopy Using Ion Imprinted Polymer

Area of Science:

• Analytical Chemistry
• Environmental Science
• Materials Science

Background:

• Accurate determination of uranium at ppb levels in environmental matrices is crucial.
• Flame Atomic Absorption Spectroscopy (FAAS) lacks sensitivity for this task, necessitating alternative methods.
• UV-Visible Spectroscopy is a common technique, but requires preconcentration for low concentrations.

Purpose of the Study:

• To develop and characterize ion-imprinted polymers (IIPs) for selective uranyl ion preconcentration.
• To establish an optimized method for uranium determination in environmental samples.
• To improve the sensitivity and accuracy of uranium analysis in natural waters.

Main Methods:

• Ion-imprinted polymers were synthesized using salicylaldoxime and 4-vinylpyridine complex, with methacrylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA).
• Polymer characterization was performed using Fourier-Transform Infrared Spectroscopy (FT-IR) and Thermogravimetric Analysis (TGA).
• Uranium (VI) was determined using UV-Visible Spectroscopy with Arsenazo III as the complexing agent in 3 M HClO4, after preconcentration at an optimal pH of 3.5–6.5.

Main Results:

• Successfully synthesized and characterized ion-imprinted polymers selective for uranyl ions.
• Established optimal preconcentration conditions (pH 3.5–6.5) for uranium.
• Demonstrated the applicability of the developed method for uranium (VI) determination in natural water samples.

Conclusions:

• Ion-imprinted polymers offer a sensitive and selective approach for uranium preconcentration.
• The developed method provides a viable technique for ppb-level uranium determination in environmental matrices.
• This approach enhances the capability for monitoring uranium contamination in natural water sources.