| Abstract: | In the past several years, capillary electrophoresis (CE) has generated considerable interest from pharmaceutical companies for control of both the chiral and achiral purity of bulk drugs and drug products. This paper evaluates the use of CE as: (1) a technique complementary to HPLC for the determination of peak homogeneity of a drug, (2) for determination of chiral purity, and (3) for determination of achiral purity. It would be greatly advantageous if CE could be used to determine both the chiral and achiral purity in a single assay. This investigation compares the results obtained for the separation of the enantiomers of duloxetine using several neutral cyclodextrins to those obtained using anionic cyclodextrins (sulfobutyl ether derivatives) as chiral selectors added to the separation buffer. In addition, it reports chiral separations obtained by using neutral cyclodextrins in a sulfonic acid-coated capillary column, which give a negatively charged capillary surface and electro-osmotic flow even in low pH buffers. The possible mechanism of separation is discussed. © 1996 Wiley-Liss, Inc. |
