COMPARATIVE STUDY FOR ENANTIOMERIC RESOLUTION OF RIVASTIGMINE BY EKC

LUCANGIOLI S.,; SCIOSCIA S.,; TRIPODI V.,; MASRIAN E.,; FRANCHI P.,; CARDUCCI C.,; KENNDLER E.

TOLEDO, ESPAÑA

Simposio; X SYMPOSSIUM ON BIOMEDICAL, BIOPHARMACEUTICAL AND INDUSTRIAL APPLICATION OF CAPILLARY ELECTROPHORESIS; 2004

In the pharmaceutical field the enantiomeric impurity for the racemic drug substances has become a stringent requirement to assure security and efficacy in the therapeutic agents. For this reason, it is necessary to have releable analysis to determine enantiomeric forms of a chiral compound. Capillary electrophoresis is a method of choice by its relevants features such as high versatility, resolution and efficacy in short time of analysis. Capillary electrokinetic chromatography (EKC) is one electrophoretic mode most frequently employed with different speudostationary phases based on cyclodextrins (CDs) natives or derivatives with different funtional groups. In the Alzeimer disease an effective acetylcholinesterase inhibitor of the carbamate type is the rivastigmine but the S form of the racemic drug is the only enantiomer of therapeutic use. In the present work the chiral resolution of the rivastigmina was achieved using a triethanolamonium phosphate buffer pH 2.5 containing native-b-cyclodextrine. A preliminary study covering different buffer types, CDs, range of pH values, nature and concentartion of chiral selector was carried out. The proposed method allows to quantify the R-form at level of 0.1% (m/m) respect to the S-form. Therefore, the confiability of the resuls make the method suitable to evaluate the quality of the rivastigmine and its final products. This suty was completed with the determination of the electrophoretic mobilities of the enantiomers and its complex constants with the chiral selector. This study allowed the interpretation of the enantiomeric migration order under influence of the different variable applied in the electrophoretic systems.