Rapid screening of DOM's metal-binding ability using a fluorescence-based microplate assay.

Area of Science:

• Environmental Chemistry
• Analytical Chemistry
• Spectroscopy

Background:

• Dissolved organic matter (DOM) plays a crucial role in metal transport and bioavailability in ecosystems.
• Accurate quantification of metal-DOM interactions is essential for understanding environmental processes.
• Existing methods for assessing metal-binding properties can be time-consuming and require larger sample volumes.

Purpose of the Study:

• To develop a rapid, low-volume method for quantifying the metal-binding ability of DOM samples.
• To utilize fluorescence properties for high-throughput screening of metal-DOM interactions.
• To assess the binding affinity of specific metals to a surface soil DOM sample.

Main Methods:

• Development of a fluorescence-based assay using 96-well microplates.
• Monitoring fluorescence quenching upon addition of increasing metal concentrations (Cu2+, Fe2+, Ni2+) to DOM samples.
• Performing measurements at different pH conditions (pH 5 and 9) to evaluate binding behavior.

Main Results:

• The developed method successfully quantifies metal-binding affinity using fluorescence quenching.
• The assay requires only 1.6 mL of DOM sample for analysis.
• Results for metal binding to a surface soil DOM sample at pH 5 and 9 are presented.

Conclusions:

• This fluorescence-based method offers a rapid and efficient approach for assessing metal-binding properties of DOM.
• The technique's low sample volume requirement makes it suitable for analyzing precious or limited environmental samples.
• The method provides valuable data for environmental monitoring and biogeochemical studies.