title: 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.
authors.affiliation: Institute of Biochemistry, Faculty of Veterinary Medicine, University of Leipzig, Leipzig, Germany.
authors.forename: Philipp
authors.initials: P
authors.lastname: Kaiser
authors.forename: Peter
authors.initials: P
authors.lastname: Surmann
authors.forename: Herbert
authors.initials: H
authors.lastname: Fuhrmann
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000295:instrumentation* / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D015394:Molecular Structure; D011108:Polymers / Q000737:chemistry*; D015203:Reproducibility of Results; D013696:Temperature; D024341:Xanthophylls / Q000302:isolation & purification
chemical_list: D011108:Polymers; D024341:Xanthophylls; C005948:astaxanthine