Method to assay coenzyme Q10 in blood plasma or blood serum

• US 20040033553A1
• Filed: 05/23/2003
• Published: 02/19/2004
• Est. Priority Date: 05/23/2002
• Status: Active Grant

• Current Assignee: Daniele Fattorini, Fabrizio Mosca, Gian Paolo Littarru, Stefano Bompadre
• Original Assignee: Daniele Fattorini, Fabrizio Mosca, Gian Paolo Littarru, Stefano Bompadre
• Inventors: Mosca, Fabrizio, Bompadre, Stefano, Fattorini, Daniele, Littarru, Gian Paolo
• Granted Patent: US 7,303,921 B2
• Time in Patent Office: Days
• US Class Current: 435/25
• CPC Class Codes: G01N 33/5735 co-enzymes or co-factors, e.g. NAD, ATP

Abstract

A method is described for determining CoQ₁₀ concentrations in plasma samples. CoQ₁₀ in the plasma sample is oxidized by treating the sample with an oxidizing agent having a redox potential higher than the redox potential of CoQ₁₀, such as, for example, para-benzoquinone. Following oxidation of the CoQ₁₀, the CoQ₁₀ in the plasma sample is extracted with an alcohol, such as, for example, 1-propanol. The alcohol extract is analyzed using direct injection into the HPLC apparatus. This method achieves a rapid, accurate analysis of plasma CoQ₁₀ levels, which can be used for monitoring the bioavailability of orally administered CoQ₁₀ used as a food supplement or as an adjunctive therapy.

Claims

1. A method for determining the concentration of CoQ₁₀ in blood plasma or blood serum, comprising the steps of:

(a) obtaining a sample of blood plasma or blood serum from a human;

(b) treating the sample with an oxidizing agent having a redox potential greater than the redox potential of CoQ₁₀;

(c) extracting the oxidized CoQ₁₀ from the sample using an alcohol; and

(d) analyzing the alcohol to determine the concentration of CoQ₁₀.

2. The method of claim 1, wherein the oxidizing agent having a redox potential greater than the redox potential of CoQ₁₀ is 1,4 benzoquinone.

3. The method of claim 2, wherein the alcohol is selected from the group consisting of n-propanol, butanol and pentanol

4. The method of claim 2, wherein the alcohol is 1-propanol.

5. The method of claim 1, wherein the step of analyzing the alcohol is performed by High Performance Liquid Chromatography.

6. A method for determining the concentration of CoQ₁₀ in blood plasma or blood serum, comprising the steps of:

(a) obtaining a sample of blood plasma or blood serum from a human;

(b) depositing an aliquot of the sample in a container;

(c) adding to the sample in the container a sufficient volume of an oxidizing agent having a redox potential greater than the redox potential of CoQ₁₀ to oxidize CoQ₁₀ in the sample;

(d) vortexing the sample containing the oxidizing agent;

(e) allowing the vortexed sample containing the oxidizing agent to stand for a sufficient period of time for the oxidizing agent to oxidize CoQ₁₀ contained in the sample;

(f) adding an alcohol to the sample containing the oxidizing agent to extract the oxidized CoQ₁₀ from the sample;

(g) vortexing the sample containing the alcohol;

(h) centrifuging the sample containing the alcohol to spin down the protein precipitate;

(i) removing an aliquot of the supernatant from the centrifuged sample and analyzing the aliquot of supernatant to determine the concentration of CoQ₁₀ in the sample.

7. The method of claim 6, wherein the oxidizing agent is 1,4 benzoquinone.

8. The method of claim 7, wherein the alcohol is selected from the group consisting of n-propanol, butanol and pentanol.

9. The method of claim 7, wherein the alcohol is 1-propanol.

10. The method of claim 6, wherein the aliquot of supernatant is analyzed using High Performance Liquid Chromatography.

11. A method for determining the concentration of CoQ₁₀ in blood plasma or blood serum, comprising the steps of:

(a) obtaining a sample of blood plasma or blood serum from a human and depositing 200 μ

l of the sample in a test tube;

(b) adding 50 μ

l of 1,4-benzoquinone solution to the sample contained in the test tube, wherein the 1,4-benzoquinone solution contains 2 mg 1,4-benzoquinone/ml solution, and vortexing the sample and 1,4-benzoquinone for about 10 seconds;

(c) allowing the test tube containing the vortexed sample to stand for about 10 minutes;

(d) adding 1 ml of 1-propanol to the test tube and vortexing the resulting the sample and the alcohol in the test tube for about 10 seconds;

(e) centrifuging the test tube at about 10,000 rpm for about 2 minutes;

(f) removing 200 μ

l of supernatant from the test tube and injecting the supernatant into a High Performance Liquid Chromatography apparatus to determine the the concentration of CoQ₁₀ in the sample.