Fluorescent probe based on hydrogel-immobilized carbon dots complex with temperature-trigger for ferric iron detection.

A novel fluorescent probe based on poly(N-isopropyl acrylamide) (p(NIPAAm-co-AAm)) immobilized carbon dots@SiO2 nanoparticles complex was synthesized for ferric iron detection through the chemical crosslinking methods, in which carbon dots@SiO2 nanoparticles complex was characterized by field emission scanning electron microscope, Fourier transform infrared spectroscopy, Ultraviolet–visible spectrophotometer and fluorescence spectrophotometer, respectively. The fluorescence quenching between p(NIPAAm-co-AAm)-CQDs and ferric iron were able to be controlled at different temperatures based on the swelling and shrinking of p(NIPAAm-co-AAm) through changing the temperature, which the principle of the probe was analyzed. The fluorescent probe could detect the ferric iron with a good linear relationship in the range of concentration from 0 to 50 μM and the limit of detection was 0.48 μM at 25 °C. [ABSTRACT FROM AUTHOR]