Rapid and simple dansylation of phenolic steroids using a two-phase system and phase transfer catalysis.
Dansylation of phenolic steroids was carried out in chloroform-water and hexane-water two-phase systems with a tetrabutylammonium salt as phase transfer catalyst. Derivatization was complete within a few minutes on shaking at room temperature. Direct injection of part of the organic phase into a normal-phase liquid chromatography system was possible. The calibration graph of ethinyl estradiol, dansylated in a chloroform-water two-phase system, was linear over three orders of magnitude with a correlation coefficient of 0.993 (n = 8). The detection limit of dansylated ethinyl estradiol was 100 pg (signal-to-noise ratio = 2). The reproducibility of the derivatization at an analyte concentration of 200 ng/ml in chloroform was 4.1% (relative standard deviation; n = 5). A mechanism is proposed for the phase transfer catalysed dansylation of phenolic compounds.
De Ruiter
C
C
Department of Analytical Chemistry, Free University, Amsterdam, The Netherlands.
Otten
R R
RR
Brinkman
U A
UA
Frei
R W
RW
D002384:Catalysis; D003619:Dansyl Compounds / Q000032:analysis*; D004997:Ethinyl Estradiol / Q000652:urine; D006801:Humans; D010636:Phenols / Q000032:analysis; D012997:Solvents; D013256:Steroids / Q000032:analysis* / Q000652:urine
D003619:Dansyl Compounds; D010636:Phenols; D012997:Solvents; D013256:Steroids; D004997:Ethinyl Estradiol