An automatic analytical system for quantitative determination of uremic middle molecules.

Abstract A system for automatic analyses of medium-sized compounds (middle molecules-MM) is described, applying gel filtration combined with gradient ion-exchange chromatography and using an automatic sample injector, motoric selector valves, and a minicomputer, which controls the system. Quantitation is performed by integrating the peak areas obtained. Using the automatic analyzer 7 MM solutes could be separated, detected, and quantified. The method permits a sampling rate of 28 samples per week. The precision of the method was 9.5%. The error in a single determination based on duplicate samples was 10% and in duplicate determinations was 7%. The automatic, analytical system is a prerequisite for performing sereening studies within a reasonable period of time. The present automatic, analytical system has been tested during a period of 3–5 years, and used in more than 4000 determinations.