A SIMPLIFIED PROCEDURE FOR THE ASSAY OF PROGESTERONE

Abstract

ABSTRACT During one year 8000 determinations of plasma progesterone have been made, using a simple petroleum ether extraction of the plasma followed by competitive protein binding analysis. The selection of the petroleum ether is crucial for the specificity, which is acceptable for the determination of progesterone during the luteal phase of the menstrual cycle and during pregnancy. The limit of sensitivity is 0.1 ng. Only 0.25 ml of plasma is needed for the determination during the luteal phase and 0.05 to 0.10 ml during pregnancy. One technician can assay 20 samples in one day with good accuracy and a precision of 7.9 per cent in the most favourable range of measurements. In research projects involving drugs the influence of these drugs on the competitive protein binding system has to be tested. Some of the samples should be further purified by thin layer chromatography as a constant check on the specificity for progesterone.