An ultrasensitive sensing platform based on fluorescence carbon dots for chlorogenic acid determination in food samples

In this work, an ultrasensitive and convenient method was established for chlorogenic acid (CGA) determination based on fluorescence quenching of carbon dots (CDs). The CDs were prepared by hydrothermal heating of citric acid and p-phenylenediamine. The proposed CDs-based sensing platform showed high selectivity and sensitivity towards CGA detection. Under optimal working conditions, the fluorescence signals of CDs decreased with increasing of CGA contents and presented linear response to CGA content in two ranges of 0.01–0.1 and 0.1–20.0 μM. The detection limits were as low as 8.87 nM and 0.12 μM. The proposed method was successfully applied to analyze CGA in real food samples. The recoveries were between 98.9 % and 106.7 % and the relative standard deviations (RSDs) were below 3.28 %. This work highlights the construction of a facial, simple, economic and highly sensitive fluorescence sensing system for CGA detection with promising application prospects in food analysis.