Correlation between LC-MS/MS and ELISA methods for quantitative analysis of desmosine-containing solutions

Area of Science:

• Biochemistry
• Biomarker Discovery

Background:

• Desmosine and isodesmosine are key crosslinking amino acids in elastin.
• Elastin provides elasticity to tissues like lungs and arteries.
• These amino acids are potential biomarkers for elastin degradation diseases, including COPD.

Purpose of the Study:

• To evaluate a newly developed ELISA for desmosine and isodesmosine quantification.
• To compare the accuracy of ELISA with isotope-dilution LC-MS/MS.

Main Methods:

• Analyzed various samples using both ELISA and LC-MS/MS.
• Determined the molar extinction coefficient of synthetic desmosine.

Main Results:

• ELISA and LC-MS/MS showed a high correlation (0.9941).
• ELISA measurements closely matched theoretical values (avg 0.94), while LC-MS/MS deviated significantly (avg 0.87 after recalculation).
• A revised molar extinction coefficient improved LC-MS/MS accuracy.

Conclusions:

• The developed ELISA provides highly accurate desmosine concentration measurements.
• ELISA is a viable and accurate in vitro diagnostic tool for assessing elastin degradation.