Separation of cationic aracyl derivatives of betaines and related compounds.
Cationic aracyl esters of betaines can be formed by alkylation with aracyl halides or trifluoromethanesulfonates. HPLC on a non-endcapped strong cation exchange (SCX) column gave high retention of these derivatives. Cation exchange HPLC may be carried out on a normal-phase (silica or alumina) column using a polar organic solvent (acetonitrile, propan-2-ol) containing an aqueous buffer with an organic cation and a hydrophilic anion. Selectivity is affected by the choice of organic solvent and buffer, e.g. alcohols decrease the retention times of hydroxybetaines such as carnitine. Retention is reduced by increasing the water content and the buffer concentration. Capillary electrophoresis migration times are affected by the choice of buffer anion, with low pH citrate buffers favoured.
Storer
Malina K
MK
Biochemistry Unit, Canterbury Health Laboratories, P.O. Box 151, Christchurch, New Zealand.
McEntyre
Christopher J
CJ
Lever
Michael
M
D001622:Betaine / Q000737:chemistry / Q000302:isolation & purification*; D002411:Cation Exchange Resins; D002412:Cations; D002851:Chromatography, High Pressure Liquid; D019075:Electrophoresis, Capillary; D012015:Reference Standards; D012997:Solvents
D002411:Cation Exchange Resins; D002412:Cations; D012997:Solvents; D001622:Betaine