Orange emission N doped carbon dots as a fluorescent and colorimetric dual-mode probe for nitrite detection and cellular imaging
A novel orange emission N doped carbon dots (N-CDs) were prepared for sensing nitrite (NO2-) with fluorescent and colorimetric dual mode. The obtained N-CDs possessed fantastic optical properties and specific response to NO2-. NO2- could induce fluorescence static quenching of N-CDs, and a friendly linear relationship was obtained in the range of 2 to 60 μM with the detection limit of 0.35 μM. More interestingly, the N-CDs exhibited ratiometric absorption signals with a visible color conversion (red-purple), which allowed to develop a simple colorimetric method for NO2- monitor in the linear range of 2-80 μM with a detection limit down to 0.13 μM. Additionally, the N-CDs were capable of monitoring NO2- in the A549 cells, which indicated its great potential in biosensing.