Nitrogen and sulfur co-doped carbon dot-based ratiometric fluorescent probe for Zn2+ sensing and imaging in living cells.

Abstract

Anear-infrared nitrogen and sulfur co-doped carbon dot (N,S-CD)-based ratiometric fluorescent probe is proposed that issynthesized via hydrothermal approach using glutathione and formamide as precursor for sensing and imaging of Zn2+. Theprepared N,S-CDs facilitate binding with Zn2+ owing to N and S atom doping. The ratio (I650/I680) of fluorescence intensity at 650nm and 680nm increased with the concentrations of Zn2+ when the excitation wavelength was 415nm. The linearity range was 0.01 to 1.0μM Zn2+with a detection limit of 5.0nMZn2+. The proposed probe was applied to label-free monitoring of Zn2+ in real samples and fluorescent imaging of Zn2+ in living cells, which confirmed its promising applications.