METHODS FOR THE DETERMINATION OF FORMALDEHYDOGENIC STEROIDS BY DIFFUSION AND BY DIRECT REACTION*

Abstract

A method is descr. for detn. of formaldehydogenic steroids, using diffusion of the formaldehyde in Conway units in place of distillation. After oxidation with periodic acid in the outer well, the sealed units are left in an oven at 85[degree] for 1 hr. The reaction mixture distills over completely and the color is simultaneously developed. Extracts of some urines were found to contain a substance which binds formaldehyde so that both its diffusion and direct reaction with chromotropic acid are inhibited. An ether-extraction step which was devised to remove this substance results in higher titers for most urine extracts, greatly improved recoveries of added cortisone, and better adherence to Beer''s law. A direct procedure, without diffusion is also descr. It is applicable to uncontaminated corticosteroid material, and permits assay of about 50 samples in 1 day.