Enhanced protocol for quantitative N-linked glycomics analysis using Individuality Normalization when Labeling with...

Area of Science:

• Glycomics
• Analytical Chemistry
• Biochemistry

Background:

• N-linked glycan analysis via liquid chromatography and mass spectrometry (LC-MS) is challenging due to their hydrophilic nature.
• Derivatization methods are crucial for improving ionization and detection sensitivity in glycan analysis.
• The Individuality Normalization when Labeling with Isotopic Glycan Hydrazide Tags (INLIGHT)™ strategy is a known method for glycan labeling.

Purpose of the Study:

• To maximize the sensitivity and separability of the INLIGHT™ glycan preparation and analysis pipeline.
• To investigate critical steps within the INLIGHT™ workflow for optimization.
• To establish optimal LC conditions for derivatized N-linked glycans.

Main Methods:

• Comparison of recombinant and nonrecombinant PNGase F sources for glycan release.
• Optimization of INLIGHT™ derivatization conditions: temperature, solvent, reaction time, and tag concentration.
• Evaluation of a C18 reverse-phase (RP) column with RPLC mobile phases for optimal LC separation.

Main Results:

• Optimized INLIGHT™ method yielded 20-100 times greater peak areas for detected N-linked glycans in fetuin and horseradish peroxidase compared to the standard method.
• Successful identification of previously undetectable low-abundance glycans, including (Fuc)1(Gal)2(GlcNAc)4(Man)3(NeuAc)1 and (Gal)3(GlcNAc)5(Man)3(NeuAc)3.
• A C18 RP column with standard RPLC mobile phases proved optimal for INLIGHT™ derivatized N-linked glycan analysis.

Conclusions:

• The optimized INLIGHT™ method substantially enhances N-linked glycan detection sensitivity and allows for the analysis of low-abundance species.
• The study provides a refined pipeline for sensitive and comprehensive N-linked glycan profiling.
• The findings support the utility of INLIGHT™ derivatization coupled with RP-LC-MS for advanced glycomics research.