Evaluation of an immunoturbidimetric microalbuminuria assay

We have evaluated an immunoturbidimetric method for the estimation of urinary albumin. The method, besides being easy to perform and cost-effective, was sensitive enough to detect an even slightly increased albumin excretion (detection limit 5 mg/l). Within-run reproducibility was 1.8 and 2.1%, and between-run reproducibility 2.9 and 4.3% in samples containing 16.1-17.8 mg/l and 50.6-54.0 mg/l of albumin, respectively. The recovery of albumin added to the samples was 98.6-106.6%. Results obtained by this method correlated well with the results obtained by radial immunodiffusion (r = 0.980, n = 44) and radioimmunoassay (r = 0.982, n = 41). The immunoturbidimetric method can be easily adapted for several clinical chemistry analysers.