Reevaluation of Direct Radioimmunoassay for Plasma cAMP Concentration

Direct radioimmunoassay for melatonin in plasma.

Measurement of plasma digoxin concentration by radioimmunoassay.

A rapid, sensitive, and precise method for measuring the plasma digoxin concentration has been developed with the radioimmunoassay technique. Seventy patients receiving digoxin were shown to have plasma digoxin concentrations between 0.4 and 5 ng./ml. Preliminary studies show that though there is a positive correlation between total daily dose and the plasma digoxin concentration, the relations...

A direct radioimmunoassay for aldosterone in unextracted serum and plasma.

We describe a novel radioimmunoassay procedure for the direct estimation of aldosterone in unextracted plasma and serum samples, in which interfering binding proteins are digested by Proteinase K (Tritirachium alkaline proteinase, EC 3.4.21.14), a powerful proteolytic enzyme. Heating at 75 degrees C for 15 min inactivates the enzyme before radioimmunoassay. Alternatively, EDTA may be used to in...

Radioimmunoassay for dexamethasone in plasma.

Until recently there has been no adequate clinical method for precisely measuring dexamethasone in blood. Studies of therapeutic dexamethasone concentrations and of its metabolism in plasma have relied on the use of radioactive dexamethasone (1-3). We report here an immunoassay in which antisera obtained from rabbits immunized with a conjugate of dexamethasone and bovine serum albumin (BSA) are...

Radioimmunoassay for flupenthixol in plasma.

We describe a radioimmunoassay for the neuroleptic drug flupenthixol, suitable for routine monitoring of its concentration in blood. Antibodies for the assay were raised in a sheep against a 7-carboxyflupenthixol/ovalbumin conjugate. The resulting assay, with [3H] flupenthixol as the label, is capable of detecting 2.0 microgram of flupenthixol per liter, in a 100-microliter plasma sample. The a...