Abstract
A competitive protein binding (CPB) analytic method for the measurement of plasma androstenedione (Δ) has been developed. An ether extract of 5 ml plasma, containing the appropriate tritiated tracer, is initially purified by a single thin layer chromatogram (TLC), as previously described for testosterone (T). The area of the chromatogram containing Δ is successively acetylated, reduced with 17 β-hydroxysteroid dehydrogenase, and rechromatographed once (TLC). CPB analysis of a batch of 12 specimens and T standards is then carried out. The method possesses high accuracy and sensitivity: 5.0 ng of Δ is recovered as 5.05 ± 0.53 ng (S.D.). The overall precision in plasma is 12.3%. The water blank is 0.08 ± 0.05 ng, and the value obtained in a castrated-adrenalectomized subject is negligible (2.2 ng/100 ml). Specificity is further indicated by failure of additional chromatography to lower the determined Δ concentration in normal subjects. The mean plasma concentrations observed in normal adults were: males 114 ± 42, females (follicular phase) 123 ± 17, females (luteal phase) 159 ± 25 ng/100 ml (S.D.). These values correspond with the ranges established by double isotope derivative dilution techniques.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
