Background: An HPLC method employing a post-column derivatization strategy using the cupric reducing antioxidant capacity reagent (CUPRAC reagent) for the determining antioxidants in plant-based materials leverages the separation capability of regular HPLC approaches while allowing for detection specificity for antioxidants.
Methods: Three different column types, namely core-shell and porous silica including two chemically different core-shell materials (namely phenyl-hexyl and C18), were evaluated to assess potential improvements that could be attained by changing from a porous silica matrix to a core-shell matrix. Tea extracts were used as sample matrices for the evaluation specifically looking at catechin and epigallocatechin gallate (EGCG).
Results: Both the C18 and phenyl-hexyl core-shell columns showed better performance compared to the C18 porous silica one in terms of separation, peak shape, and retention time. Among the two core-shell materials, the phenyl-hexyl column showed better resolving power compared to the C18 column.
Conclusions: The CUPRAC post-column derivatization method can be improved using core-shell columns and suitable for quantifying antioxidants, exemplified by catechin and EGCG, in tea samples.
Digital Object Identifier (DOI)
This study was made possible, in part, through funds from the Food and Drug Administration through grant RFA-FD-14-001.
Haque, Syed A. and Cañete, Socrates Jose P., "HPLC-CUPRAC Post-Column Derivatization Method for the Determination of Antioxidants: A Performance Comparison Between Porous Silica and Core-Shell Column Packing" (2018). Kentucky Tobacco Research and Development Center Faculty Publications. 21.