Detection of vitamins A and E by tandem mass spectrometry

Patent metadata

Field	Value
Publication number	US-10215765-B2
Application number	US-201113231866-A
Country	US
Kind code	B2
Filing date	Sep 13, 2011
Priority date	Sep 15, 2010
Publication date	Feb 26, 2019
Grant date	Feb 26, 2019

Abstract

Methods are described for measuring the amount of one or more of vitamin A, α-tocopherol, and the combination of β-tocopherol and γ-tocopherol in a sample. More specifically, mass spectrometric methods are described for detecting and quantifying one or more of vitamin A, α-tocopherol, and the combination of β-tocopherol and γ-tocopherol in a sample.

First claim

That which is claimed is:

1. A method for determining the amount of vitamin A in a sample by tandem mass spectrometry, said method comprising:
a. subjecting vitamin A from a sample to ionization under conditions suitable to produce one or more ions detectable by mass spectrometry; and
b. determining the amount of one or more of said ions by tandem mass spectrometry, wherein tandem mass spectrometry comprises fragmenting a vitamin A precursor ion having a mass to charge ratio of about 269.30±0.80 into one or more fragment ions comprising a fragment ion having a mass to charge ratio of about 105.00±0.80;
wherein the amount of the one or more fragment ions determined in step (b) is related to the amount of vitamin A in the sample.

2. The method of claim 1 wherein the sample is subjected to liquid chromatography (LC) prior to ionization.

3. The method of claim 2 , wherein said LC is reverse phase LC.

4. The method of claim 2 wherein said LC and said ionization are conducted with on-line processing.

5. The method of claim 1 wherein the sample is subjected to high performance liquid chromatography (HPLC) prior to ionization.

6. The method of claim 1 , wherein said ionization comprises ionization with an atmospheric chemical ionization (APCI) source.

7. The method of claim 1 , wherein the sample comprises a biological sample.

8. The method of claim 7 , wherein the biological sample is from a human patient suspected of having a deficiency or an excess of vitamin A.

9. The method of claim 1 , wherein the sample comprises serum or plasma.

10. The method of claim 1 , wherein tandem mass spectrometry is conducted by multiple reaction monitoring, precursor ion scanning, or product ion scanning.

11. The method of claim 1 further comprising determining the amount of one or more additional analytes simultaneously with the determination of the amount of vitamin A.

12. The method of claim 11 , wherein the one or more additional analytes comprises one or both of α-tocopherol and combined β-tocopherol and γ-tocopherol.

13. The method of claim 12 wherein the one or more additional analytes comprises α-tocopherol, and determining the amount of α-tocopherol comprises fragmenting an α-tocopherol precursor ion having a mass to charge ratio of about 430.47±0.80 into one or more fragment ions comprising a fragment ion having a mass to charge ratio of about 165.03±0.80.

14. The method of claim 12 wherein the one or more additional analytes comprises combined β-tocopherol and γ-tocopherol, and determining the amount of combined β-tocopherol and γ-tocopherol comprises fragmenting β-tocopherol and γ-tocopherol precursor ions having a mass to charge ratio of about 416.35±0.80 into one or more fragment ions comprising a fragment ion having a mass to charge ratio of about 151.00±0.80.

15. The method of claim 12 wherein the one or more additional analytes comprises α-tocopherol and combined β-tocopherol and γ-tocopherol.

Assignees

• Chan Sum
• Jiang Qibo
• Quest Diagnostics Invest Inc

Inventors

• Chan Sum
• Jiang Qibo

Classifications

• Y10T436/24

  Nuclear magnetic resonance, electron spin resonance or other spin effects or mass spectrometry · CPC title

• G01N33/82 Primary

  involving vitamins {or their receptors} · CPC title

• H01J49/0045

  characterised by the fragmentation or other specific reaction · CPC title

• G01N2560/00

  Chemical aspects of mass spectrometric analysis of biological material · CPC title

• G01N33/48

  Biological material, e.g. blood, urine (G01N33/02, G01N33/26, G01N33/44, G01N33/46 take precedence); Haemocytometers (counting blood corpuscules distributed over a surface by scanning the surface G06M11/02) · CPC title