Development of a double‐antibody sandwich ELISA for rapid detection to C‐peptide in human urine

Abstract

&NA; C‐peptide level is recognized as an important indicator of diabetes diagnosis. A sensitive and specific double‐antibody sandwich enzyme‐linked immunosorbent assay for the detection of C‐peptide based on double antibody sandwich method was studied in this paper. The rabbit and hen were innunized with PLL‐C‐peptide and BSA‐C‐peptide respectively to obtain specific Yolk antibody (IgY) and polyclonal antibody used to construct the sandwich ELISA for the measurement of C‐peptide. The limit of detection was 0.51 &mgr;g/mL and the half maximal inhibitory concentration (IC50) was 3.26 &mgr;g/mL. The method developed in the study showed no evident cross‐reactivity with other similar analogs. The detection standard curve of C‐peptide exhibited a good linearity (R2 = 0.9896, n = 15). 17 types of the urine of diabetes patients on c‐peptide levels compared with the hospital type of diabetes information, with a conclusion of a high consistent rate. Therefore, the methods could be selectively used for rapid screening of C‐peptide in human urine, and the type of diabetes has some referential significance. Graphical abstract Figure. No caption available.