Evaluation of chromatographic performance of three C18 columns for avenanthramides separation

Phenolic amides contained in oats (Avenanthramides; AVNs) are biologically active substances with strong antioxidant activity. In this paper, we evaluated efficiency of three C18 chromatographic columns (Symmetry, XBridge, Cortecs) with different particle technology and particle sizes for the separation of three major avenanthramides (AVN A, AVN B, AVN C). We compared columns in terms of retention times, retention factors of AVNs and in terms of other parameters such as number of theoretical plates, height equivalent to a theoretical plate, reduced plate height, resolution and in terms of peak symmetry, respectively. Limits of detection and limits of quantification of AVNs on all columns were calculated. Retention results of AVNs on individual columns showed a significant reduction in retention times of AVNs on solid core column with a particle size 2.7 μm compared to columns with particle size 3.5 μm. Within columns with 3.5 μm particles, separation on Symmetry C18 column appeared to be more efficient than on the XBridge C18 column. In general, results achieved on Cortecs C18 column can be considered as the best in terms of both separation efficiency and retention times.