Isotachophoresis: the concepts of resolution, load capacity and separation efficiency. II: Experimental evaluation

Resolution, load capacity and separation efficiency in isotachaphoresis are experimentally evaluated and the results are compared with the theoretically expected values. The theoretical and experimental results show good agreement and confirm the reliability of the transient-state model. The importance of the dimensionless separation number and load capacity for the determination and standardization of experimental performance conforms with theory. It is shown that, in view of these two parameters, the pH of the leading electrolyte is the best rationale for optimization, whereas the pH of the sample has only restricted possibilities. Steady-state configurations in which constituents are not migrating in order of decreasing effective mobilities are shown and discussed

Determination of uric acid in serum using isotachophoresis

An operational system is described for the isotachophoretic determination of uric acid in serum, making use of column coupling. The method has been compared with a standard enzymatic procedure. With the present technique small amounts of serum (ca. 3 μl) can be applied without any pretreatment. Urate recovery was 99.0–100.5%. Under the non-physiological measuring conditions used, 12–28% of control serum uric acid was bound to macromolecules of molecular weight exceeding 25,000. The day-to-day variations of the isotachophoretic procedure were smaller than those of the enzymatic method, whereas standard deviations were comparable. The isotachophoretic procedure is less influenced by certain metabolites

Profiling of uremic serum by high-resolution gas chromatography—electron-impact, chemical ionization mass spectrometry

A fast and reliable procedure for gas chromatographic profiling of components in ultrafiltrated uremic serum has been developed, using glass capillary columns. Sample pretreatment consists of ultrafiltration, evaporation and silylation. Some twenty components are identified by electron-impact and chemical ionization mass spectrometry. A comparison is made between profiles of sera from a series of uremic patients, before and after hemodialysis, and from non-uremic sera. Significant differences are found between these profiles. A "dialysis ratio" is introduced as a parameter for the removal of retained components by hemodialysis treatment

Uremie een chemisch-analytische benadering

Veal symptomen van het 'uremischsyndroom' zijn terug te voeren op een verstoring van de bloedzuiverende functie van de nier. metabolieten en afbraakproduktenbopen zich dan in het Iicbaam op. Voor de analyse van deze stoffen bestaan thans efficiënte scheidings- en detectivetechnieken