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D A Dayton

Publications and source records attributed to D A Dayton.

6 recordsLinked to original sources
PubMed1978

Time--concentration studies by high-performance liquid chromatography of metabolites removed during hemodialysis.

Reversed-phase high-performance liquid chromatography was used to study the efficiency of hemodialysis. The method, previously used to study uremic hemodialysate, was also found useful for analyzing other uremic biofluids, such as serum and urine. Samples of blood (centrifuged to obtain cell-free serum) and hemodialysate were simultaneously collected from selected patients at regular intervals during the entire 6-hour hemodialysis treatment. These samples were filtered through membranes to remove particulates and proteins and were then analyzed by use of a 60-cm muBondapak-C18 column, an aqueous sodium acetate/methanol gradient, and detection at 254 nm. The identification of components in the eluate was based on retention times, ultraviolet absorption spectra, and mass spectra. From the amounts of several metabolites in the various physiological fluid pools during hemodialysis, we concluded that they mostly originate from tissue fluids. We also observed that the concentrations of most components in serum and hemodialysate fluctuated regularly with time.

Chromatography, High Pressure Liquid↗
PubMed1976

Reversed-phase liquid-chromatographic analysis of hemodialysate from uremic patients.

With reversed-phase high-performance liquid chromatography we effected rapid and efficient separation of metabolites present in hemodialysate fluid from uremic patients on the artificial kidney. With an aqueous sodium acetate/methanol gradient as mobile phase, more than 50 ultraviolet-absorbing constituents were resolved in a 70-min chromatogram of a 100-mul sample of dialysate. Many of the metabolites could be detected in concentrations below 0.1 mg/liter. From results of ultraviolet spectrophotometric analysis and the gas- and liquid-chromatographic properties of standards, half the observed chromatographic peaks have been characterized or identified. The method has been shown to be more than 10-fold faster than comparable separations by ion-exchange techniques.

Chromatography, Gas↗