Thin-Layer Chromatographic Separation of Chiral drugs on Molecularly Imprinted Chiral Stationary Phases

This report describes the TLC separation of two classes of chiral drug, including β-blocking drugs and non-steroidal antiinflammatory drugs (NSAID) on molecularly imprinted chiral stationary phases, in the same way as has been performed by HPLC. Several molecularly imprinted polymers (MIP) were prepared using the enantiomers of either the β-blocking drugs, R- (+)-propranolol, R-(+)- or S-(-)-atenolol, or the NSAID, S-(+)- naproxen and S-(+)-ibuprofen, as print molecules. Three different functional monomers, ITA, MAA, and VPD were employed in the imprinting process. The polymers prepared in the presence of MAA or VPD could be coated as thin layers on glass supports, but not those prepared in the presence of ITA. The MIP of R-(+)- propranolol, with 5% acetic acid in acetonitrile as mobile phase, resolved the racemate of propranolol into two spots, but tailing spots were obtained. The MIP prepared from S-(+)-naproxen, with 1% acetic acid in THF-heptane, 1 + 1, as mobile phase, resolved the racemate of ketoprofen into enantiomers, with a good separation factor (α = 5.2).