Isotachophoretic analysis of peptides.

Area of Science:

• Analytical Chemistry
• Biochemistry
• Separation Science

Background:

• Capillary-tube isotachophoresis (cITP) is a powerful separation technique.
• Accurate qualitative and quantitative analysis of biomolecules like plasma kinins, angiotensin, and glutathiones is crucial.
• Standardization of cITP methods is needed for reliable inter-laboratory comparisons.

Purpose of the Study:

• To establish optimal operating conditions for cITP analysis of specific biomolecules.
• To introduce a novel qualitative index for cITP measurements.
• To validate the proposed index for its robustness and inter-laboratory comparability.

Main Methods:

• Capillary-tube isotachophoresis (cITP) was employed.
• A potential gradient detector was utilized for analysis.
• Operating conditions were systematically optimized for target analytes.

Main Results:

• Established operating conditions for qualitative and quantitative determination of plasma kinins, human angiotensin, and glutathiones.
• Introduced the potential unit (PU) as a qualitative index for cITP with a potential gradient detector.
• Demonstrated that the PU value is independent of operating conditions, ensuring inter-laboratory data comparability.
• Achieved a coefficient of variation of less than 1.69% for the PU index.

Conclusions:

• The developed cITP method provides reliable qualitative and quantitative analysis of key biomolecules.
• The potential unit (PU) offers a standardized and robust qualitative index for cITP.
• The PU value facilitates consistent and comparable results across different laboratories and operating conditions.