A ratiometric and far-red fluorescence “off-on” sensor for sequential determination of copper(II) and L-histidine based on FRET system between N-acetyl-L-cysteine-capped AuNCs and N,S,P co-doped carbon dots
An “on–off–on” fluorescent phosphorus/nitrogen co-doped carbon dot (PNCD) probe was explored for the determination of Cr(vi) and dopamine resulting from the inner filter effect (IFE).