Capillary electrochromatography with novel stationary phases IV. Retentionbehavior of glycosphingolipids on porous and non-porous octadecyl sulfonated silica

In this investigation, capillary electrochromatography (CEC) with a novel s tationary phase proved useful for the separation of neutral and acidic glyc osphingolipids (GSLs). Four different gangliosides, namely G(M1a), G(D1a), G(D1b) and G(T1b), served as the acidic GSLs model solutes. The following f our GSLs: galactosylceramide (GalCer), lactosylceramide (LacCer), globotria osylceramide (Gb(3)Cer) and globotetraosylceramide (Gb(4)Cer) served as the typical neutral GSLs. The stationary phase, octadecyl sulfonated silica (O DSS), consisted of octadecyl functions bonded to a negatively charged layer containing sulfonic acid groups. Porous and non-porous ODSS stationary pha ses were examined. The retention behavior of the acidic and neutral GSLs wa s examined over a wide range of elution conditions, including the nature of the electrolyte and organic modifier and the pH of the mobile phase. The p orous ODSS stationary phase yielded the separation of the four different ga ngliosides using a hydro-organic eluent of moderate eluent strength whereas the non-porous ODSS stationary phase permitted the separation of the four neutral GSLs with a mobile phase of relatively high eluent strength. (C) 20 00 Elsevier Science B.V. All rights reserved.