A chiral stationary phase for the enantioselective separation of ketoprofen has been prepared by molecular imprinting, in which 4- vinylpyridine (functional monomer) and ethylene glycol dimethacrylate were copolymerised in the presence of (S)-ketoprofen. Racemic ketoprofen was efficiently resolved on the molecular imprinting polymer. Capacity factor (k_s') of (S)-ketoprofen and separation factor (α) were 9.52 and 1.52, respectively. Furthermore, the polymer was able to separate ketoprofen from the structurally related ibuprofen and naproxen. Effects of concentration of acetic acid in the mobile phase, flow rate and temperature were studied. The change of enthalpy and entropy were estimated. It was found that enantioselective separation was enthalpy controlled.

Key words: ketoprofen, THERMODYNAMIC ANALYSIS, HPLC, MATRIX POLYMERIZATION, STATIONARY PHASE