Indirect fluorescence determination of lactate and pyruvate in single erythrocytes by capillary electrophoresis.
A scheme of using fluorescein as the fluorophore for indirect detection of anions was demonstrated. This system is quite stable at a fluorescein concentration of 100 microM even without any other buffer components. Different injection modes affect the limit of detection (LOD). A LOD of about 20 amol was obtained for lactate under optimal conditions. Lactate and pyruvate in the intracellular fluid of erythrocytes were measured in this manner. The average amounts in a single erythrocyte for lactate and pyruvate are 1.3 and 2.1 fmol, respectively, or a ratio of 1.6 for pyruvate to lactate. Variations of the absolute amounts and the ratios are fairly large among a group of 27 cells examined. This is consistent with the difference of cells in size and composition. Although the migration times changed by up to 20% during a series of runs from the influence of concomitants in the cells, the migration time ratio was maintained around 1.072 with 3% relative standard deviation.
Xue
Q
Q
Department of Chemistry, Iowa State University, Ames 50011.
Yeung
E S
ES
D000328:Adult; D004586:Electrophoresis / Q000379:methods*; D004912:Erythrocytes / Q000737:chemistry*; D005069:Evaluation Studies as Topic; D019793:Fluorescein; D005452:Fluoresceins; D006801:Humans; D007773:Lactates / Q000032:analysis*; D019344:Lactic Acid; D008297:Male; D011773:Pyruvates / Q000032:analysis*; D019289:Pyruvic Acid; D013050:Spectrometry, Fluorescence
D005452:Fluoresceins; D007773:Lactates; D011773:Pyruvates; D019344:Lactic Acid; D019289:Pyruvic Acid; D019793:Fluorescein