Retention Behavior of Aromatic Amines with Some Ionic Liquids Mobile Phase in Semi-micro HPLC

Abstract

This research was aimed at investigating the retention behavior of aromatic amines with some ionic liquid mobile phases in semi-micro HPLC to explain the unclear separation mechanism. Aromatic amines (m-aminophenol, benzylamine, N,N-dimethylaniline, p-aminobenzoic acid, p-aminophenol, aniline, p-toluidine and N-methylaniline) were examined. The retention behavior of aromatic amines is greatly affected by the column equilibration time, ionic liquid concentration, mobile phase pH and alkyl chain length on the imidazolium cation of the ionic liquid. Semi-micro HPLC was used to increase separation power and sensitivity, and in addition to save on the mobile phase of the expensive ionic liquid. The separation mechanism involves ionic and hydrophobic interactions.