High-performance liquid chromatographic enantioseparation of (RS)-bupropion using isothiocyanate-based chiral derivatizing reagents.

A high-performance liquid chromatographic (HPLC) method for enantioseparation of bupropion was developed using two isothiocyanate-based chiral derivatizing reagents, (S)-1-(1-naphthyl) ethyl isothiocyanate, (S)-NEIT, and (R)-α-methyl benzyl isothiocyanate, (R)-MBIT. The diastereomers synthesized with (S)-NEIT were enantioseparated by reversed-phase HPLC using gradient elution with mobile phase containing water and acetonitrile, whereas diastereomers synthesized with (R)-MBIT were enantioseparated using triethyl amine phosphate buffer and methanol. Derivatization conditions were optimized and the method was validated for accuracy, precision and limit of detection. The limit of detection was found to be 0.040-0.043 µg/mL for each of the diastereomers prepared with (S)-NEIT.