Dual Detection of Procalcitonin and C-reactive Protein with an Up-converting Nanoparticle Based Lateral Flow Assay.

Procalcitonin (PCT) and C-reactive protein (CRP) are significant complementary inflammatory markers, and their simultaneous detection is of substantial value. In this article, a rapid, simple and cost-effective method for the dual quantitative detection of PCT and CRP in serum is discussed. Two UCNPs of similar size and morphology, but with a different emission spectrum, were prepared for the simultaneous detection of PCT and CRP by lateral flow assay (LFA) technology in a direct method. With the developed dual test strips and signal read system, the assay results present a limit of detection (LOD) of 0.12 ng/mL and 0.24 μg/mL for PCT and CRP, respectively. In addition, both of the coefficients of variation and positive and negative concordance rates for PCT or CRP are well compared with those of the traditional method. The dual detection of PCT and CRP have shown great application potential in medical diagnosis and treatment guidance.