Development of Indirect Competitive Immuno-Microarray for the Detection of Microalbuminuria

摘要

Despite much advancement of protein microarray in the past years, the commonly adopted format, two-color labeling and sandwich assays are still challenged with additional labeling and requirement of antibody pairs. Competition strategy is an appealing approach for protein quantification in traditional immunoassay. However, protein microarrays employing competitive strategy are rarely discussed. In this study, two methods based on direct competitive (dcAssay) and indirect competitive (icAssay) assays for detecting microalbuminuria (mAlbU) have been established. Compared with dcAssay approach, icAssay showed a much wider detection dynamic range (50-0.08 μg/mL) and a better quantitative ability in terms of linearity (correlation coefficient, 0.9948) and accuracy (20.6% and 7.6% for the inter-assay and intra-assay variability). Moreover, the results obtained from icAssay and the rate nephelometry approach used for measuring mAlbU showed a high correlation of 0.900 (p = 0.001). In conclusion, the results provide us with an encouraging approach for protein microarray quantification with no need of sample labeling and antibody pairs which overcome the challenges with traditional approaches. It is anticipated that the established platform may serve as a promising tool for mAlbU screening in a high-throughput and cost-effective way.