Low temperature oligosaccharide analytical system and method

Patent metadata

Field	Value
Publication number	US-12405254-B2
Application number	US-202217675284-A
Country	US
Kind code	B2
Filing date	Feb 18, 2022
Priority date	Feb 18, 2022
Publication date	Sep 2, 2025
Grant date	Sep 2, 2025

Abstract

A novel analytical system and method to analyze complex carbohydrates such as human milk oligosaccharides by low-temperature High-Performance Anion Exchange Chromatography with Pulsed Amperometric Detection and High-resolution Mass Spectrometry (HPAE-PAD-MS). The analytical system controls the temperature of the column, electrochemical detector, and ion removal device at or below 15° C. The HPAE-PAD workflow with high-resolution mass spectrometry provides useful molecular structure information. It facilitates the detection of milk oligosaccharides, particularly unknown structures, without the use of analytical standards.

First claim

What is claimed is:

1. A method of analyzing an oligosaccharide sample, the method comprising:
injecting the oligosaccharide sample into a chromatography column of the chromatography system;
flowing a mobile phase into the chromatography column to separate the oligosaccharide sample into one or more analytes that elute off the chromatography column at different times;
flowing the mobile phase from the chromatography column into an electrochemical detector to detect one or more analytes;
flowing the mobile phase from the electrochemical detector into an ion removal device;
removing at least ions of one charge from the mobile phase in the ion removal device; and
flowing the mobile phase to a mass spectrometer;
wherein the chromatography column, electrochemical detector, and the ion removal device are all at a temperature of 15° C. or less;
wherein less than 5% of the oligosaccharide sample is epimerized.

2. The method of claim 1 , wherein the electrochemical detector is a pulsed amperometric detector.

3. The method of claim 2 , wherein the pulsed amperometric detector comprises a gold electrode.

4. The method of claim 1 , wherein the chromatography column, electrochemical detector, and the ion removal device are all at a temperature of 10° C. or less.

5. The method of claim 1 , wherein the mobile phase comprises NaOH and NaOAc.

6. The method of claim 1 , wherein the sample comprises oligosaccharides.

7. The method of claim 1 , wherein the ion removal device is a suppressor.

8. The method of claim 1 , wherein the mass spectrometer comprises an electrospray ionization source to vaporize the analytes into ions in a gas phase.

9. The method of claim 1 , wherein the one or more analytes are detected by the mass spectrometer.

Assignees

• Dionex Corp

Inventors

• Tian Tian
• Liu Yan

Classifications

• G01N2030/326

  pumps · CPC title

• G01N2030/027

  Liquid chromatography · CPC title

• G01N30/64

  Electrical detectors · CPC title

• G01N30/32

  of pressure or speed (G01N30/36 takes precedence) · CPC title

• G01N30/30

  of temperature · CPC title