Chiral separation of ketoprofen on an achiral NH 2 column by HPLC using vancomycin as chiral mobile phase additive

A high-performance liquid chromatographic method for chiral separation of ketoprofen racemate was developed. (R)- and (S)-ketoprofen enantiomers were separated on a LiChrosorb NH 2 column (250 mm × 4.6 mm, i.d 5 µm) at 20 °C, using 2-propanol/potassium dihydrogen phosphate buffer (pH 6.0, 0.05 M) (50:50 v/v). Containing vancomycin as the mobile phase, at a flow rate of 0.8 ml min −1 and detection wavelength of UV, the detector was set at 310 nm. Under these conditions, ketoprofen enantiomers could be separated with a selectivity factor ( α ) of 2.172 and a resolution (Rs) of 4.78 using extremely low concentrations of the vancomycin chiral additive.