Solid-phase permethylation of glycans for mass spectrometric analysis

Area of Science:

• Analytical Chemistry
• Glycobiology
• Mass Spectrometry

Background:

• Oligosaccharide analysis is crucial for understanding biological processes.
• Traditional permethylation methods are often time-consuming and require extensive cleanup.
• Microscale techniques offer potential for faster and more efficient derivatization.

Purpose of the Study:

• To develop a miniaturized, rapid, and quantitative method for oligosaccharide permethylation.
• To adapt permethylation for microscale reactors compatible with mass spectrometry.
• To improve efficiency and reduce sample handling in glycan analysis.

Main Methods:

• Developed a microscale derivatization approach using sodium hydroxide in microspin columns or fused-silica capillaries.
• Analyzed oligosaccharides by mixing with methyl iodide in dimethyl sulfoxide solution and infusing through microreactors.
• Utilized matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) for analysis.

Main Results:

• Achieved effective derivatization in under a minute at the microscale.
• Successfully permethylated picomole amounts of various glycan types (linear, branched, sialylated, neutral).
• Minimized oxidative degradation and peeling reactions, reducing the need for extensive cleanup.

Conclusions:

• The miniaturized permethylation approach is rapid, efficient, and suitable for microscale glycan analysis.
• This method simplifies sample preparation for mass spectrometry-based glycomic studies.
• The technique is broadly applicable to diverse oligosaccharide structures.