Removal of contaminating substances before gas-liquid-chromatographic determination of aldosterone in urine.

This paper deals with removal of contaminants before gas-chromatographic determination of aldosterone in urine. Urine is incubated with beta-glucuronidase, which hydrolyzes all beta-glucuronides except aldosterone-18-glucuronide. The contaminants (the aglycones released and other methylene chloride-soluble substances) are extracted with methylene chloride. Solvolysis of the aqueous phase liberates aldosterone from aldosterone-18-glucuronide, which then is extracted with methylene chloride and oxidized by use of periodic acid. The resulting lactone can be easily separated by one-dimensional thin-layer chromatography and determined by gas-liquid chromatography.