High pressure liquid chromatography antioxidants

For many decades, the standard technique for measuring carotenoids has been high-pressure liquid chromatography (HPLC). This time consuming and expensive chemical method works well for the measurement of carotenoids in serum, but it is difficult to perform in human tissue since it requires biopsies of relatively large tissue volumes. Additionally, serum antioxidant measurements are more indicative of short-term dietary intakes of antioxidants rather than steady-state accumulations in body tissues exposed to external oxidative stress factors such as smoking and UV-light exposure. 

RC Rose, AM Bode. Analysis of water-soluble antioxidants by high-pressure liquid chromatography. Biochem J 306 101-105, 1995. 

High Pressure Liquid Chromatography is expected to separate molecules of unreacted antioxidant from its degradation by products. For example, phosphite yields a phosphate when reducing a hydroperoxide into an alcohol. Phosphite and phosphate are easily separated by HPLC which allows envisaging the stabilization scheme and its kinetics [27]. 

After the extraction step has been completed, the antioxidants and other additives present in the solvent can be readily analyzed. The majority of the analytical methods used for measuring the antioxidant content of polymer extract solutions are based on chromatography, such as high performance or high pressure liquid (HPLC), gas (GC), and gel permeation (GPC) or size exclusion (SEC). As most polymer antioxidants contain a phenyl ring or other chromophoric moiety in their structure, UV detection (usually between 200 and 280 nm) is ideally suited for their measurement. The chromatogram shown in Figure 1 aptly demonstrates the utility of... 

In this review we have summarized the results obtained by different chromatographic techniques and a variety of sample preparation methods for the analysis of antioxidants in polymers and in solutions. Efficient techniques including liquid and gas chromatography, mass spectrometry, traditional low pressure extraction techniques and newer high pressure techniques have been developed. These have made possible the accurate quantification and identification of antioxidants. The newer techniques offer versatile tools for further developments in this area of polymer analysis. 

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