Tritium isotope effect in high-pressure liquid chromatography of vitamin D metabolites.
A significant chromatographic isotope effect is reported for 1,25-dihydroxyvitamin D3 in a wide variety of HPLC separation systems. The effect is also observed for 24,25-dihydroxyvitamin D3. Retention times differ from less than 1% up to 4% depending on the separation system and the degree and position of tritium substitution. Such an effect must be corrected for whenever both labeled and unlabeled vitamin D metabolites are used in HPLC cochromatography or assay recovery studies.
Worth
G K
GK
Department of Endocrinology and Diabetes, Sir Charles Gairdner Hospital, Nedlands, Western Australia.
Retallack
R W
RW
D015650:24,25-Dihydroxyvitamin D 3; D002117:Calcitriol / Q000032:analysis; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004100:Dihydroxycholecalciferols / Q000032:analysis; D012997:Solvents; D014316:Tritium; D014807:Vitamin D / Q000302:isolation & purification* / Q000378:metabolism
D004100:Dihydroxycholecalciferols; D012997:Solvents; D014316:Tritium; D014807:Vitamin D; D015650:24,25-Dihydroxyvitamin D 3; D002117:Calcitriol