Immunochromatographic assay to detect α‐tubulin in urine for the diagnosis of kidney injury

BACKGROUNDS: Shortening of primary cilia in kidney epithelial cells is associated with kidney injury and involved with the induced level of α‐tubulin in urine. Therefore, rapid detection and quantification of α‐tubulin in the urine samples could be used to the preliminary diagnosis of kidney injury. METHODS: Cellulose‐based nanobeads modified with α‐tubulin were used for the detection probe of competitive immunochromatographic (IC) assay. The concentration of α‐tubulin in the urine samples was determined by IC assay and compared with the amount determined by Western blotting analysis. RESULTS: The relationship between α‐tubulin concentration and the colorimetric intensity resulted from IC assay was determined by logistic regression, and the correlation coefficient (R (2)) was 0.9948. When compared to the amount determined by Western blotting analysis, there was a linear relationship between the α‐tubulin concentrations measured by the two methods and the R (2) value was 0.823. CONCLUSIONS: This method is simple, rapid, and adequately sensitive to detect α‐tubulin in patient urine samples, which could be used for the clinical diagnosis of kidney injury.