Quantitation of Omega Fatty Acids by HPLC and Charged Aerosol Detection - - Chromatography Online
Quantitation of Omega Fatty Acids by HPLC and Charged Aerosol Detection


The Application Notebook

Omega-3 and -6 fatty acids are essential compounds required for normal growth. Omega-3 consumption is purported to have a number of health benefits, e.g., cancer prevention, cardiovascular disease prevention, and improved immune function. Although both omega-3 and -6 fatty acids can give rise to eicosanoid-signaling molecules (prostaglandins, prostacyclins, thromboxanes, and leukotrienes), the omega-6 eicosanoids are generally proinflammatory. A person's diet requires a balance of omega fatty acids at suitable levels.

Omega lipids found in foods are commonly determined after extraction, hydrolysis, and derivatization for measurement by gas chromatography (GC). Analyte derivatization can adversely affect temperature-sensitive functional groups on specialized lipids. High-performance liquid chromatography (HPLC) with ultraviolet detection at low wavelengths limits solvent selection and increases the likelihood of matrix interference.


Figure 1
Here is a direct inverse-gradient HPLC method with charged aerosol detection. Fourteen underivatized standard omega acids were identified — along with a number of other analytes — with near-baseline resolution. This method was used to measure omega-3, -6, and -9 fatty acids in traditional and commercially produced meat, fish, oils, and over-the-counter supplements. Charged aerosol detection is mass sensitive and provides the most consistent response for nonvolatile and some semivolatile analytes of all HPLC detection techniques. It works by measuring the charge induced on analyte particles and is not dependent on light scattering, which has large variability and generally lower sensitivity.

Charged aerosol detection has been successfully used to characterize lipids of all classification, including phospholipids (reversed and normal phase), acylglycerides, phytosterols, and free fatty alcohols. This method complements the free-fatty acids method using higher specificity for these analytes on a newly developed Thermo Scientific Acclaim C30 reversed-phase column.

Conditions and Sample Preparation

The experimental setup and sample preparation procedures are described in Poster Note LPN 2931-02, Thermo Fisher Scientific, Inc. (formerly Dionex Corp.).

Conclusions

After saponification to release the fatty acids, samples were neutralized and directly analyzed for omega-3, -6, and -9 fatty acids using this HPLC method with charged aerosol detection. The method can be used to analyze omega fatty acids from a variety of sources. The mobile phase is compatible with mass spectrometry, allowing the possibility of identifying unknown analytes.

Scan to receive complete application note.

Thermo Fisher Scientific, Inc. (formerly Dionex Corp.)
1228 Titan Way, P.O. Box 3603, Sunnyvale, CA 94088
tel. (408) 737-0700, fax (408) 730-9403
Website: http://www.thermoscientific.com/dionex/

ADVERTISEMENT

blog comments powered by Disqus
LCGC E-mail Newsletters
Global E-newsletters subscribe here:




 

LCGC COLUMNISTS 2014

Sample Prep Perspectives | Ronald E. Majors: Ron Majors, established authority on new column technologies, keeps readers up-to-date with new sample preparation trends in all branches of chromatography and reviews developments.
LATEST: UV Detector Problems


Perspectives in Modern HPLC | Michael W. Dong: Michael W. Dong is a senior scientist in Small Molecule Drug Discovery at Genentech in South San Francisco, California. He is responsible for new technologies, automation, and supporting late-stage research projects in small molecule analytical chemistry and QC of small molecule pharmaceutical sciences. LATEST: Superficially Porous Particles: Perspectives, Practices, and Trends


MS — The Practical Art | Kate Yu: Kate Yu brings her expertise in the field of mass spectrometry and hyphenated techniques to the pages of LCGC. In this column she examines the mass spectrometric side of coupled liquid and gas-phase systems. Troubleshooting-style articles provide readers with invaluable advice for getting the most from their mass spectrometers. LATEST: Radical Mass Spectrometry as a New Frontier for Bioanalysis


LC Troubleshooting | John Dolan: LC Troubleshooting sets about making HPLC methods easier to master. By covering the basics of liquid chromatography separations and instrumentation, John Dolan is able to highlight common problems and provide remedies for them. LATEST: Problems with Large-Molecule Separations


More LCGC Chromatography-Related Columnists>>

LCGC North America Editorial Advisory Board>>

LCGC Europe Editorial Advisory Board>>

LCGC Editorial Team Contacts>>


Source: The Application Notebook,
Click here