A Conjugated Polymer Fluorescent Sensor for Continuous Identification of Copper(II) and Pyrophosphate in Blood Serum and Synovial Fluid.

A novel "on-off-on" super-sensitive conjugated polymer fluorescence sensor (PPE-DPA) was developed and it was applied to realize the continuous recognition of Cu2+ and pyrophosphate (PPi). The fluorescence intensity decreased linearly with the change of Cu2+ from 0.05 to 5.0 μmol L-1 and the limit of detection was 24 nmol L-1. The fluorescence intensity was linearly enhanced with the increase of PPi from 0.5 to 12.0 μmol L-1 and the limit of detection was 230 nmol L-1. In addition, this method was applied to detect PPi in the blood serum and synovial fluid of patients with arthritis and satisfactory results were obtained. Thus, the PPE-DPA is not only an effective tool for detecting Cu2+ and PPi in samples, but also presents a potential way to diagnose arthritis.