COMPETITIVE PROTEIN BINDING ASSAY OF TESTOSTERONE

Competitive protein-binding assay for 25-hydroxycholecalciferol.

1. A competitive protein-binding assay for plasma 25-hydroxycholecalciferol was developed, using Sephadex LH-20 columns for the isolation of the sterol and a partially purified protein from rat serum as the binding protein. 2. The mean plasma 25-hydroxycholecalciferol in eighteen male and female normal volunteers was 38 5 SD 14 pmol/ml (1 5.2 & 5.6 nglml). 3. Levels of 25-hydroxycholecalciferol...

Quantitation of plasma testosterone by improved competitive protein-binding technique.

A method is described for quantitation of testosterone in plasma from females and males. The principal operations of extraction, chromatographic fractionation, and competitive protein-binding assay can be completed for eight duplicate samples in a single day. Experimental data used in the development of the test and the rationale for the specific operations and conditions are presented. The spe...

Rapid, specific assay for plasma cortisol by competitive protein binding.

We describe a modified competitive protein-binding method for assay of plasma cortisol. Plasma samples are deproteinized by dilution with an ethanol/phosphate buffer, followed by heating at 100 degrees C for 2 min. Horse serum is used as the source of transcortin. Free radioactivity is separated from the protein-bound component by partition into liquid scintillation counting within 60 min. The ...

A Competitive-Binding Assay forGlycopeptideAntibioticsof the VancomycinClass

A solid-phase enzyme-receptor assay (sPcR.A) has been developed for glycopeptide antibiotics of the vancomycin class such as teicoplanin, vancomycin, ristocetin, avoparcin, actaplanin,A-47934, A-41 030, and A-3551 2-B. The assay exploitsthe mechanismof most action of these antibiotics, which is based on their interaction with acyl-D-alanyl-Dalanine, a constituentof the walls of mostgrowingbacte...

Enzyme-Linked Immunosorbent Assay Competitive Binding Inhibition