Mobile phase additives for enhancing the chromatographic performance of astaxanthin on nonendcapped polymeric C₃₀‐bonded stationary phases

Abstract

Astaxanthin shows peak deformation and reduced peak area response when eluted with methanol and methyl tert-butyl ether on nonendcapped polymeric C30-bonded HPLC phases. The present study tested different column manufacturers, column batches, and ten mobile phase additives including acids, bases, buffers, complexing and antioxidant agents for improvement of peak shape and peak area response. Concerning chromatographic benefits and feasibility, ammonium acetate was found to be the best additive followed by triethylamine for all columns tested. Variation of the mobile phase pH equivalent and the column temperature showed no synergistic effects on peak shape and peak area response. Results indicate that peak tailing and variation of peak area response are due to different on-column effects. Possible mechanisms of the observed phenomenon will be discussed.

Characterization of enhanced-fluidity liquid hydrophilic interaction chromatography for the separation of nucleosides and nucleotides

“…Triethylamine (TEA) has been frequently used as a mobile phase modifier to reduce tailing of Lewis basic analytes. 32,33 Two bases that are widely used in organic synthesis and described as superbases due to their strong basicity in both aqueous and organic solvents were also considered and compared to…”