Simple procedure for measuring total protein in urine.

We describe a procedure for measuring total protein in urine. The method is simple, sensitive, and free of interference from drugs that are known to affect other commonly used methods. The CV for a 1.1 g/liter urine control in daily, routine use is 4.6%. The procedure involves adsorbing the protein onto cellulose powder, binding of Ponceau S dye by the protein, washing away excess dye, and eluting the bound dye into dilute NaOH for colorimetry. Comparison of results by this method with those by the biuret and turbidimetric procedures showed good agreement in those cases where the specimens were suitable for assay by the comparison methods.