New method for determination of 21-hydroxy corticosteroids

Abstract

Energy after etchings, MeV Irradiation time, min Chemical separation Oxygen content, Ag/g 11.8 20 Without 0.23 ± 0.02 11.8 20 Elimination of Na on 0.19 ± 0.02 11.5 35 hydrated Sb2Os Steam distillation of 0.23 ± 0.02 11.1 20 H2SiF6 Without 0.20 ± 0.02 10.7 20 Elimination of Na on 0.23 ± 0.02 10.0 20 hydrated Sb205 Without 0.20 ± 0.02 8.2 15 Without 0.21 ± 0.02 8.2 15 Without 0.23 ± 0.02 12.0 20 Zone Refined Aluminum Without <0.04 11.6 15 Without <0.04 11.4 60 Without <0.05Sodium can be separated by its retention on hydrated antimony pentoxide ( 19) after dissolving the sample in hydrochloric acid (6N). Fluorine, partially retained in the absence of aluminum (20), is completely eluted in the presence of this element. We have confirmed, by steam distillation of hydrofluoric acid at 200 °C ( 21), that the period of 110 minutes really corresponds to fluorine-18 (Figure 3). RESULTSThe oxygen content was calculated using the so-called "equivalent thickness" method ( 22) and the activation curve determined by Markowitz. The results obtained are presented in Table II.The only detectible half-life in the case of the purest aluminum samples (zone refined aluminum) is 15 hours correspond-(19) F. Girardi and E.