Sh. Hansen et al., SEPARATION OF BASIC DRUG SUBSTANCES OF VERY SIMILAR STRUCTURE USING MICELLAR ELECTROKINETIC CHROMATOGRAPHY, Journal of pharmaceutical and biomedical analysis, 13(4-5), 1995, pp. 489-495
Small molecules having very similar molecular structure - some even wi
th the same mass over charge - are not trivial to separate by capillar
y electrophoresis in free solution. However, addition of surfactants t
o the electrophoretic buffer and thus using the principle of micellar
electrokinetic chromatography may provide separation with high resolut
ion. The use of zwitterionic and nonionic surfactants is demonstrated
and an example of how a developed system may be used for drug purity t
esting is given.