One-dimensional simulation of lanthanide isotachophoresis using COMSOL
Derek R Dixon1, Sue B Clark, Cornelius F Ivory
1The Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Washington State University, Pullman, WA 99164-2710, USA.
Electrophoresis
|April 24, 2012
Summary
This study simulates rare earth element separation using isotachophoresis. Adding acetate complexes to the buffer prevents lanthanide peak splitting, improving forensic signature analysis.
Area of Science:
- Analytical Chemistry
- Separation Science
Background:
- Electrokinetic separations offer rapid methods for rare earth element analysis.
- Isotachophoresis (ITP) is a technique used for separating charged species.
- Forensic analysis requires precise identification of elemental signatures.
Purpose of the Study:
- To simulate the concentration and separation of trivalent lanthanide cations using isotachophoresis.
- To investigate the effect of complexation ligands on lanthanide separation.
- To optimize buffer conditions for improved separation and peak resolution.
Main Methods:
- A one-dimensional finite element simulation was developed using COMSOL v4.0a.
- Simulated the isotachophoretic separation of lanthanum, terbium, and lutetium.
- Investigated the role of α-hydroxyisobutyric acid (HIBA) and acetate complexation.
Main Results:
- Lanthanide:HIBA complexes alone in a 10 mM HIBA buffer caused peak splitting for lutetium.
- The addition of lanthanide:acetate complexes eliminated peak splitting.
- Reducing HIBA concentration to 7 mM increased analyte stack migration speed.
Conclusions:
- Acetate complexation is crucial for resolving peak splitting in lanthanide isotachophoresis.
- Buffer composition significantly impacts the efficiency and speed of electrokinetic separations.
- Simulation provides a valuable tool for optimizing separation conditions for rare earth elements.
