Thin layer chromatographic resolution of some 2‐arylpropionic acid enantiomers using L‐(−)‐serine, L‐(−)‐threonine and a mixture of L‐(−)‐serine and L‐(−)‐threonine‐impregnated silica gel as stationary phases

Abstract

Impregnated silica TLC plates with L-(-)-serine and L-(-)-threonine and a mixture of L-(-)-serine and L-(-)-threonine (1:1) as chiral selectors were prepared to use as chiral stationary phases (CSPs) in thin layer chromatography. The resolution of the enantiomers of 2-arylpropionic drugs, including ibuprofen, ibuproxam, ketoprofen, pranoprofen, benoxaprofen, flurbiprofen and tiaprofenic acid was investigated on these CSPs. A mobile phase system of acetonitrile-methanol-water (16:4:0.5, v/v/v) was used. The spots were detected with iodine vapours and the detection limits were found to range between 0.25 and 0.5 micro g/mL for all racemic compounds investigated. The effect of temperature, pH and concentration of the impregnating chiral selectors on resolution has been studied.

Direct resolution and quantitative analysis of flurbiprofen enantiomers using microcrystalline cellulose triacetate plates: applications to the enantiomeric purity control and optical isomer determination in widely consumed drugs

“…Conversely, only a partial resolution was achieved by Aboul‐Enein et al . (), using l ‐(−)‐serine, l ‐(−)‐threonine or their mixtures as impregnating agents of silica gel plates and eluting with acetonitrile–methanol–water mixtures.…”

“…More recently, racemic flurbiprofen has been resolved into its enantiomers using the chiral coated stationary phase (CCSP) technique, by impregnating commercially available achiral silica gel plates with (−)‐brucine (Bhushan and Thiongo, ). l ‐(−)‐Serine, l ‐(−)‐threonine and their mixtures were also investigated as impregnating agents in the CCSP technique for flurbiprofen enantioresolution (Aboul‐Enein et al ., ), and acetonitrile–methanol–water mixtures as eluents. The resolution of the optical antipodes of flurbiprofen was also achieved via the impregnation of achiral silica gel plates with l ‐arginine and the two‐dimensional elution with ethanol containing a few drops of acetic acid (Sajewicz et al ., ).…”

Amino acids as chiral selectors in enantioresolution by liquid chromatography

“…Impregnation was carried out by mixing l ‐Arg with the silica gel slurry (Bhushan and Parshad, ) or by immersion of plates in the solution of l ‐Arg (Sajewicz et al ., ). l ‐(−)‐Serine and l ‐(−)‐threonine have been used as chiral impregnating reagents for TLC resolution of some 2‐arylpropionic acids (Aboul‐Enien et al ., , ). Some of these results are summarized in Tables .…”

“…l ‐(−)‐Serine and l ‐(−)‐threonine and a mixture of the two optically pure amino acids were used for impregnation by dipping the precoated TLC plates of silica gel (without a fluorescent indicator) in their solutions for resolution of enantiomers of flurbiprofen and a few other nonsteroidal anti‐inflammatories (NSAIDs; Aboul‐Enien et al ., ). (±)‐Flurbiprofen resolved into its enantiomers only on the plates impregnated with the mixture of l ‐serine and l ‐threonine (0.05 g each) using acetonitrile–methanol–water (16:4:0.5, v/v); there was no resolution on the plates impregnated with either l ‐serine or with l ‐threonine.…”

Resolution of (±)‐ibuprofen using (−)‐brucine as a chiral selector by thin layer chromatography

“…Enantioseparation of (±)-ibuprofen using thin-layer chromatographic plates impregnated with L-arginine (Bhushan and Prashad, 1996), (−)-brucine (Bhushan and Thiong'o, 1999) and L-(−) serine (Aboul Enein et al, 2003) as a chiral selector and using molecular imprinting polymer technique (Suedee et al, 2001) has been reported.…”