Capillary electrophoretic methods have been developed to separate the enant
iomers of methylphenidate (MPH) and dextromoramide. For MPH separation was
achieved with heptakis (2,6-di-O-methyl)-beta -cyclodextrin (DMCD) as chira
l selector in a 100 mM phosphoric acid buffer adjusted to pH 3.0 with triet
hanolamine. Commercial samples Of D,L-erytho-MPH HCl and D,L-threo-MPH HCl
were analysed using the method. There was no evidence of the presence of D,
L-threo-MPH HCl in D,L-etytho-MPH HCl and vice versa. The ratio of the enan
tiomers was determined for each diasteroisomer. Hydroxypropyl-beta -cyclode
xtrin was the chiral selector of choice for the chiral separation of the en
antiomers of moramide. The separation which gave a resolution of about 3.5
was achieved in 4 min using only a 6 cm of length of capillary. In a sample
of dextro-R-moramide tartrate only a small quantity (4.9% w/w) of levo-S-m
oramide was detected with this method. (C) 2001 Elsevier Science B.V. All r
ights reserved.