Fluorescent carbon dots for highly sensitive diosmetin sensing

Abstract

In this paper, a single signal fluorescent sensor of nitrogen-doped carbon dots (N-CQDs) was established for the micro-determination of diosmetin. In this determination platform, the as-developed N-CQDs with yellow fluorescence were prepared through a facile hydrothermal method with p-phenylenediamine and ascorbic acid as the precursors containing nitrogen and carbon. The as-developed N-CQDs had a classical surface structure and surprising fluorescence stability. The maximum excitation and emission peaks were located at 372 and 528 nm, respectively. Under the optimal sensing conditions, the as-prepared N-CQDs held preeminent immunity towards possible interfering substances. The determination platform’s fluorescence intensity was quenched because of the static quenching and inner filter effect. The fluorescence weakening changes displayed an attractive linear relationship with diosmetin in range of 0.5–150 μM, and the linear equation was ln(F0/F) = 0.014[Q]–0.055 with the R2 of 0.9975 and the detection limit of 0.049 μM. The determination platform could be applied for the trace detection of diosmetin in river water and bovine serum samples. The corresponding recovery rate was 94.8 %–108.8 %, exhibiting that it was a facile and efficient fluorescence sensing strategy.