A novel ratiometric fluorescent sensing platform for superoxide anion (O₂⁻) detection.

The incorporation of suffocated polystyrene nanoparticles (PS-SO₃H) as a non-interfering internal calibration is benefit for ratiometric fluorescent sensing of O₂⁻.

The ratio of I₅₄₄/I₄₆₃ linearly increases with the increasing of O₂⁻ concentration in the range of 0 nM-6.0 μM with a detection limit as low as 3.4 nM.

We have successfully synthesized core-shell PS-SO₃H@Tb/G NCPs.