Chiral separation of loxoprofen sodium by high performance liquid chromatography

A method for chiral separation of four loxoprofen sodium optical isomers was developed by high performance liquid chromatography on the chiral stationary phase of cellulose tris (4-methylbenzoate) (Chiralcel OJ-R). The effects of pH, concentration and type of the buffer, and organic modifier's kind in the mobile phase on the resolution and retention were investigated. The good resolution was obtained with the mobile phases of methanol/0.1 mol/L acetic acid-triethylamine (or 0.5 mol/L HClO4-NaClO4) at pH 3.0 = 80/20. The resolutions with over 1.7 for all continuous peaks were shown at. the mobile phase conditions. The peak sequence was identified as (1'R,2R), (1'S,2R), (1'R,2S.), (1'S,2S). The investigated results facilitate to understand the recognized mechanism of the cellulose-based chiral stationary phase.