Universal method for determining electrolyte temperatures in capillary electrophoresis.

Area of Science:

• Analytical Chemistry
• Separation Science

Background:

• Joule heating in capillary electrophoresis (CE) causes temperature increases, creating
• hot spots
• at capillary ends, limiting analysis accuracy.

Purpose of the Study:

• To develop a universal method (UMET) for accurate electrolyte temperature determination in all CE conditions.
• To create a simplified method (SUMET) for rapid temperature prediction in CE experiments.

Main Methods:

• UMET measures current versus voltage at different voltages, processed by an iterative algorithm.
• SUMET utilizes one current-voltage measurement and two empirical equations for temperature prediction.
• Instrument-specific parameters for SUMET were determined using UMET data across various electrolytes and capillary types.

Main Results:

• UMET accurately determined electrolyte temperatures in both efficiently and inefficiently cooled regions.
• SUMET provided rapid and accurate temperature predictions, validated by measuring a temperature-sensitive protein-DNA complex dissociation rate.
• Empirical parameters for a Beckman MDQ CE instrument were generated for SUMET.

Conclusions:

• UMET and SUMET offer robust solutions for managing Joule heating in CE.
• These methods enhance the reliability and precision of CE analyses by enabling accurate temperature control and prediction.
• SUMET is poised for routine use in CE for efficient temperature management.