Antioxidants Are No Accident

Recently we learned about a paper published by a team in Poland describing their work on the analysis of anti-oxidants. We wanted to share this work with the AHPA community.
Barbara Kusznierewicz and her colleagues from Gdansk University of Technology have developed a method to analyze antioxidants in complex mixtures by HPLC with post-column derivatization and UV/Vis detection. The authors studied three well-known reagents routinely used in colorimetric assays to measure antioxidant activity. They determined that Diammonium 2,2′-azinobis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and Folin-Ciocalteu reagent (FCR) were best suited for post-column derivatization of antioxidants after they were separated on reversed-phase HPLC column.
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Researches optimized HPLC conditions as well as post-column parameters such as concentration of post-column reagent, duration of derivatization reaction and reaction temperature. Trolox and 20 other phenolic compounds were investigated and scientists were able to demonstrate good correlation between Trolox equivalent antioxidant capacity (TEAC) determined by HPLC with post-column derivatization and standard colorimetic assay. This method was successfully applied to analysis of extracts from sloe fruits and mirabelle plums and allowed to calculate concentration of individual antioxidants as well as TE antioxidant capacity.


Pickering Laboratories strives to provide new post-column applications, and the instruments and chemistry to support these applications. It is our philosophy to provide a complete solution and customer support. We plan to follow-up this interesting research with some development of our own to see if we can optimize the post-column technique further. 
The full version of the paper can be found in the Wiley online library:
REFERENCE:
Kusznierewicz, B., Piasek, A., Bartoszek, A., Namiesnik, J., “The Optimisation of Analytical Parameters for Routine Profiling of Antioxidants in Complex Mixtures by HPLC Coupled Post-column Derivatization,” Phytochemical Analysis, 22, 392-402 (2011)