Evaluation of Retention Behavior and Stability of Novel Trifunctional Biphenyl Phase

Description:
Biphenyl columns are currently available from several HPLC column manufacturers. Their biphenyl phases are only mono-functional. In this study, tri-functional biphenyl stationary phase was modified on a core shell silica and double end-capping was done at high reaction temperature. Tri-functional biphenyl stationary phase was compared with mono-functional biphenyl stationary phase not only for measurement of hydrogen bond capacity, hydrophobicity and steric selectivity but also for a peak shape of a metal chelating compound and a basic compound. Furthermore stability of each biphenyl stationary phase was evaluated under both acidic and basic pH conditions. Although phenyl stationary phase shows higher hydrogen bond capacity than alkyl stationary phases, biphenyl stationary phase showed the highest hydrogen bond capacity. Such a high hydrogen bond capacity leaded unique separation selectivity when separating o-, m-, p-methylhippuric acid and vanilin. Proposed trifunctional biphenyl stationary phase showed the most stable under both acidic and basic pH conditions.