A dual-label time-resolved fluorescence immunoassay for the simultaneous determination of cystatin C and β 2 -microglobulin in urine

• Published in: British journal of biomedical science Vol. 74; no. 4; pp. 193 - 197
• Main Authors: Liu, Y, Liu, Y H, Bei, W J, Wang, K, Cui, T T, Li, H L, Wu, D X, Chen, S Q, Tan, N, Chen, J Y
• Format: Journal Article
• Language: English
• Published: England 02-10-2017
• Subjects: dual-label time-resolved fluorescence immunoassay; cystatin-C; Contrast-induced nephropathy; β2-microglobulin
• ISSN: 0967-4845
• DOI: 10.1080/09674845.2017.1334740

Contrast media is widely used in clinical diagnostic and interventional procedures, but may cause damage to the kidney, that is, contrast-induced nephropathy. This study was to establish a dual-label time-resolved fluorescence immunoassay (TRFIA) for the simultaneous determination of renal function markers cystatin-C (Cys-C) and β
-microglobulin (β
-MG) for the early diagnosis and follow-up surveillance of contrast-induced nephropathy.
A sandwich immunoassay was used to detect the concentration of Cys-C, and the competitive immunoassay was used to detect the concentration of β
-MG in 50 samples of urine. The performance of this dual-label TRFIA was evaluated and compared with commercial assays.
The sensitivity for Cys-C detection was 1.26 ng/ml, the average recovery was 99.36%; The sensitivity for β
-MG detection was 2.13 ng/ml, the average recovery was 100.18%. Bland-Altman analysis showed that the dual-label TRFIA method and the commercial kits had a good agreement, suggesting they can be used interchangeably in clinical urine analysis.
The present dual-label TRFIA has high sensitivity, specificity and accuracy in clinical sample analysis. This method can be used for the early diagnosis and follow-up surveillance of the contrast-induced nephropathy.