Rapid, competitive enzymoimmunoassay for albumin in urine

In this solid-phase competitive enzymoimmunoassay for albumin in human urine, antiserum to human serum albumin labeled with horseradish peroxidase (EC 1.11.1.7) is incubated with solid-phase-bound human serum albumin in the presence of sample or standard. Results obtained correlate well (r = 0.96) with those of an established fluoroimmunoassay. The present assay covers the range 0.9 to 200 mg/L and can be performed within 1 h. These characteristics, together with the simplicity of the assay protocol, make it very useful for monitoring low concentrations of albumin in urine. Detection of such minimal albuminuria allows initiation of therapy that may prevent development of clinical proteinuria and associated diabetic nephropathy.