Method for structural analysis of organic compound

Patent metadata

Field	Value
Publication number	US-11545350-B2
Application number	US-202117237273-A
Country	US
Kind code	B2
Filing date	Jun 28, 2021
Priority date	Apr 27, 2020
Publication date	Jan 3, 2023
Grant date	Jan 3, 2023

Abstract

One mode is a method for the structural analysis of an organic compound by MALDI mass spectrometry, including: a sample preparation process (S1) which includes preparing a sample by mixing a specimen containing an organic compound to be analyzed with a predetermined matrix at a mixture ratio within a range from 1:5 to 1:5000 in molar ratio; a mass spectrometry process (S3) which includes irradiating the prepared sample with a laser beam having a spot size equal to or smaller than 15 μm to generate ions originating from a component of the specimen in the sample, and performing a mass spectrometric analysis of the generated ions; and an analyzing process (S4) which includes detecting, from a mass spectrum acquired in the mass spectrometry process, ions including product ions resulting from in-source decay, and estimating the structure of the organic compound to be analyzed based on information concerning the ions.

First claim

The invention claimed is:

1. A method for a structural analysis of an organic compound by matrix assisted laser desorption/ionization mass spectrometry, the method comprising:
a sample preparation process which includes preparing a sample by mixing a specimen containing an organic compound to be analyzed with a predetermined matrix at a mixture ratio within a range from 1:5 to 1:5000 in molar ratio;
a mass spectrometry process which includes irradiating the prepared sample with a laser beam having a spot size equal to or smaller than 15 μm to generate ions originating from a component of the specimen the sample, and performing a mass spectrometric analysis of the generated ions; and
an analyzing process which includes detecting, from a mass spectrum acquired in the mass spectrometry process, ions including product ions resulting from in-source decay, and estimating a structure of the organic compound to be analyzed based on information concerning the ions.

2. The method for a structural analysis of an organic compound according to claim 1 , wherein the organic compound is a peptide, protein or glycan.

3. The method for a structural analysis of an organic compound according to claim 2 , wherein the organic compound is a peptide, and the product ions include both an ion resulting from cleavage of a main chain of the peptide and an ion resulting from cleavage of a side chain of the peptide.

4. The method for a structural analysis of an organic compound according to claim 1 , wherein the matrix has a partial structure for absorbing ultraviolet laser light, a partial structure for donating a proton or cation, and a partial structure for making the matrix soluble in a solvent.

5. The method for a structural analysis of an organic compound according to claim 4 , wherein the partial structure for absorbing ultraviolet laser light is an aromatic ring, the partial structure for donating a proton or cation is a carboxyl group, and the partial structure for making the matrix soluble in a solvent is a hydroxyl group.

6. The method for a structural analysis of an organic compound according to claim 4 , wherein the matrix is α-cyano-4-hydroxycinnamic acid or 2,5-dihydroxybenzoic acid.

7. The method for a structural analysis of an organic compound according to claim 1 , wherein a dried-droplet method or thin-layer method is used for preparing the sample in the sample preparation process.

8. The method for a structural analysis of an organic compound according to claim 1 , wherein the sample is prepared on a sample plate which is made of glass and has a smooth, clean surface in the sample preparation process.

Assignees

• Shimadzu Corp
• Univ Hiroshima

Inventors

• Tanaka Koichi
• Yamamoto Takushi
• Yamaguchi Manaho
• Izumi Shunsuke

Classifications

• G01N33/0047

  Organic compounds · CPC title

• G01N33/6851

  Methods of protein analysis involving laser desorption ionisation mass spectrometry · CPC title

• H01J49/164 Primary

  Laser desorption/ionisation, e.g. matrix-assisted laser desorption/ionisation [MALDI] (sample holders H01J49/0418) · CPC title

• G01N27/62 Primary

  by investigating the ionisation of gases, e.g. aerosols; by investigating electric discharges, e.g. emission of cathode · CPC title

• G01N27/628

  and a beam of energy, e.g. laser enhanced ionisation · CPC title