Mass spectrometric determination of eicosapentaenoic acid and docosahexaenoic acid

Patent metadata

Field	Value
Publication number	US-10534008-B2
Application number	US-201715635509-A
Country	US
Kind code	B2
Filing date	Jun 28, 2017
Priority date	Sep 16, 2010
Publication date	Jan 14, 2020
Grant date	Jan 14, 2020

Abstract

The invention relates to the detection of DHA and EPA. In a particular aspect, the invention relates to methods for detecting DHA and EPA by mass spectrometry and kits for carrying out such methods.

First claim

That which is claimed is:

1. A method for determining an amount of one or more omega-3 fatty acids in a sample by mass spectrometry, the method comprising:
(i) ionizing said one or more omega-3 fatty acids from the sample to generate one or more omega-3 fatty acid ions detectable by mass spectrometry;
(ii) determining an amount of said one or more omega-3 fatty acid ions and docosahexaenoic acid (DHA)- 2 H 5 or eicosapentaenoic acid (EPA)- 2 H 5 internal standard by single mass spectrometry; and
(iii) correlating the amount of said one or more omega-3 fatty acid ions to the amount of one or more omega-3 fatty acids in the sample, wherein said one or more omega-3 fatty acids comprises docosahexaenoic acid (DHA) and/or eicosapentaenoic acid (EPA), wherein a lower limit of detection of the method for DHA is between about 1 μmol/L and 0.25 μmol/L and a lower limit of detection of the method for EPA is between about 1 μmol/L and 0.67 μmol/L.

2. The method of claim 1 , wherein said ionizing comprises atmospheric pressure chemical ionization (APCI).

3. The method of claim 2 , wherein said APCI is in negative ionization mode.

4. The method of claim 1 , wherein said ionizing comprises electrospray ionization (ESI).

5. The method of claim 1 , wherein said one or more ions comprise an ion with a mass to charge ratio (m/z) of 327.2 ±0.5.

6. The method of claim 1 , wherein said one or more ions comprise an ion with a mass to charge ratio (m/z) of 301.2 ±0.5.

7. The method of claim 1 , wherein said sample comprises human serum or plasma.

8. The method of claim 1 , wherein said sample is subjected to a hydrolyzing agent prior to ionization.

9. The method of claim 8 , wherein said hydrolyzing agent is an acid.

10. The method of claim 1 , wherein said one or more omega-3 fatty acids is subjected to liquid/liquid extraction prior to ionization.

11. The method of claim 1 , wherein said one or more omega-3 fatty acids is purified by liquid chromatography prior to ionization.

12. The method of claim 11 , wherein said liquid chromatography comprises high performance liquid chromatography (HPLC).

Assignees

• Quest Diagnostics Invest Inc

Inventors

• Goldman Scott M
• Neidich Julie A

Classifications

• H01J49/168

  field ionisation, e.g. corona discharge (atmospheric pressure corona discharge per se H01T19/00) · CPC title

• Y10T436/24

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

• Y10T436/255

  including use of a solid sorbent, semipermeable membrane, or liquid extraction · CPC title

• H01J49/004

  Combinations of spectrometers, tandem spectrometers, e.g. MS/MS, MSn · CPC title

• H01J49/145

  using chemical ionisation · CPC title