Fast minimicroassay of serum retinol (vitamin A) by capillary zone electrophoresis with laser-excited fluorescence detection.
In this paper, we present a fast minimicroassay of serum vitamin A by capillary zone electrophoresis with laser-excited fluorescence detection. A 60 cm x 50 microns I.D. fused-silica capillary was used for the separation, and the polymer coating was burned off 20 cm from the cathodic end to form a detection window. The buffer system consisted of 50 mM sodium phosphate plus 10 mM sodium chloride at pH 7.8. A helium-cadmium laser set at 325 nm was used for excitation, and the fluorescence of the vitamin A-retinol-binding protein complex was monitored at 465 nm using a photodiode. The stray and scattered radiation were removed by two special filters. Using this system, about 8 nl of serum sample were injected for direct analysis without any sample preparation. The analysis time for each sample was less than 6 min, and subfemtomole levels of vitamin A in human or animal blood could be easily detected. Therefore, the method is potentially useful for finger-prick vitamin A analysis, especially for babies and young children.
Division of Science, Northeast Missouri State University, Kirksville 63501.
Y
Y
Ma
Z
Z
Wu
H C
HC
Furr
C
C
Lammi-Keefe
N E
NE
Craft
D002021:Buffers; D004586:Electrophoresis; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D007834:Lasers; D013050:Spectrometry, Fluorescence; D014801:Vitamin A / Q000097:blood*
D002021:Buffers; D007202:Indicators and Reagents; D014801:Vitamin A