Fluorescent sensing of pyrophosphate anion in synovial fluid based on DNA-attached magnetic nanoparticles.

In this work, a new fluorescent method for sensitive detection of pyrophosphate anion (P2O7(4-), PPi) in the synovial fluid was developed using fluorophore labeled single-stranded DNA-attached Fe3O4 NPs. The sensing approach is based on the strong affinity of PPi to Fe3O4 NPs and highly efficient fluorescent quenching ability of Fe3O4 NPs for fluorophore labeled single-stranded DNA. In the presence of PPi, the fluorescence would enhance dramatically due to desorption of fluorophore labeled single-stranded DNA from the surface of Fe3O4 NPs, which allowed the analysis of PPi in a very simple manner.