THE DEVELOPMENT AND VALIDATION OF A COMPETITIVE, MICROTITER PLATE ENZYME-IMMUNOASSAY FOR HUMAN ALBUMIN IN URINE

We have described a fast, simple and sensitive microtiter scale, solid phase, competitive enzymeimmunoassay (EIA) for the determination of u rinary albumin. The albumin used in the test system was purified by th e combination of PEG precipitation and DEAE-cellulose column chromatog raphy. in this EIA, microtiter plates were coated with rabbit antihuma n albumin IgG, and incubated with HRP-albumin conjugate with either sa mple or standards. O-phenylenediamine (OPD) and H2O2 solution was used as substrate for HRP. Results obtained correlate well (r=0.994) with those of an in-house RIA in which same antibody and standards were use d as in ELA. The present assay covers the range of 0.5 to 10 mg/L and can be performed in 2 hours. The detection limit was 0.15 mg/L of albu min. Within - assay coefficient of variation was 8.1% and 6.6% and bet ween - assay variation was 10.6% and 8.6% at 1.25 and 2.5 mg/L respect ively.