HPLC separation of ibuprofen and mefenamic acid using molecularly imprinted polymer as stationary phase

Abstract

A simple high-performance liquid chromatographic method for the assay of ibuprofen and mefenamic acid in tablets is described. This method was developed by using self-prepared molecularly imprinted polymers (MIPs) as the stationary phase. MIPs are synthesized using non-covalent method by the free radical polymerization of template, functional monomer and an excess of crosslink monomers resulting in organic materials. The resulting bulk material was then ground into 25-44μm particles and packed into analytical columns. The effect of functional monomers/crosslinking ratio and the concentration of acetonitrile in the mobile phase were studied. Ibuprofen and mefenamic acid were efficiently resolved on the polymer. The retention time of ibuprofen and mefenamic acid were approximately 19.69±0.36min and 46.27±1.23min, respectively. Linearity was observed from 3.13-8.33g/l for ibuprofen and 0.3-0.9g/l for mefenamic acid, with the coefficients of determination (r2) of 0.9977 and 0.9958. The limits of detection (LOD) of ibuprofen and mefenamic acid were found to be respectively 0.42g/l and 0.06g/l, while the limits of quantitation (LOQ) were 1.41g/l and 0.20g/l, respectively. The self-prepared MIP was successfully applied to the commercial tablet analysis and the result showed a good accuracy with -1.33 ∼ -1.8% and -0.8 ∼ +1.33% for ibuprofen and mefenamic acid.