Enantiomerization study of atropine and its semipreparative enantioseparation along with (1 RS,2 SR)-(±)-ephedrine on polyacrylamide column using high-performance liquid chromatography

Enantiomerization of atropine was studied at ambient temperature using analytical chiral polyacrylamide column under reversed phase conditions without the use of external stimulants such as heat or catalysts; mobile phase consisting of polar organic solvents (methanol-0.2% acetic acid in water, 60:40, v/v) with detection at 230 nm was successful for resolving enantiomers of atropine and (1RS,2SR)-(±)-ephedrine. Addition of small amount of acetic acid in mobile phase was found to be essential for enantioseparation. The same mobile phase composition was found successful to investigate enatiomerization of atropine during routine runs on chromatographic time scale. The enantiomerization rate of (S)-(-)-hyoscyamine and (R)-(+)-hyoscyamine was found to be different but insignificant to result in the formation of non-racemic mixture. The analytical method developed was easily augmented to the semipreparative separation and recovery of enantiomers of drug in mg scale. The sample obtained was found to be free of enatiomerization product. The analytical method was successful for the determination of enantiomeric composition in pharmaceutical dosage form.