ÜBER NEUTRALSTEROIDE IM BLUT

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Abstract
Experiments are presented which were designed to determine the best methods for extraction, purification and hydrolysis of neutral steroids in human blood plasma. A combination of ethyl acetate and benzene appears best for extraction of free steroids of high and low polarity but its use is accompanied by the extraction of a greater amount of unspecific material in comparison to the extraction by chloroform or benzene. For purification of steroid extracts from fats, lipids and unspecific chromogens, a liquid-liquid partition by means of a separatory funnel followed by a short counter-current distribution was found to be satisfactory. When 70% ethanol was used as the lower phase and a mixture of hexane-pentane as the upper phase, loss of C-19 steroids was negligible. These extracts are suitable for direct paper chromatography without further purification. Silicagel chromatography does not lead to a satisfactory separation of C-21 and C-19 steroids. To hydrolyze C-21 steroid glucuronides, the usual incubation with [beta]-glucuronidase is sufficient but in order to obtain best results with C-19 steroid glucuronides, the incubation must last 3-4 days. Continuous ether extraction at pH 1 and hot acid hydrolysis led only to incomplete saponification of androsterone sulfate and dehydroisoandrosterone sulfate.