Development of a lateral flow immunoassay of C-reactive protein detection based on red fluorescent nanoparticles

We have developed a reliable and rapid immunoassay based on a facile synthesis of fluorescent nanoparticles integrated in immunochromatography technique to quantitatively detect C-reactive protein (CRP). The method is based on a sandwich immunoassay using the Nile-red doped nanoparticles/CRP monoclonal antibody conjugate. The method is simple and fast, with a detection limit of 0.091 mg/L. It provides quantitative analysis in the range of 0.1-160 mg/L, which is adequate for detecting CRP of acute inflammatory or cardiovascular disease. This strategy displayed a good reproducibility and stability to straightforwardly analyze the plasma samples without complicated washing steps, thereby reducing the operating procedures for non-professionals and promoting the detection efficiency and the whole detection process can be completed in 3 min. This approach for carrying out immunoassays can be applied to the detection of CRP in the point-of-care tests.