A carbon dots-CdTe quantum dots fluorescence resonance energy transfer system for the analysis of ultra-trace chlortoluron in water

• A novel FRET system was constructed base on high quantum yielding water-soluble CDs as donor, and CdTe QDs as acceptor.
• FRET system was used for the analysis of chlortoluron for the first time.
• The effect of critical parameters for the detection were studied in detail.
• The FRET platform was developed with high sensitive and selective.

In this paper, a fluorescence resonance energy transfer (FRET) system between fluorescence carbon dots (CDs, donor) and CdTe quantum dots (CdTe, acceptor) was constructed, and a novel platform for sensitive and selective determination of chlortoluron was accordingly proposed. It was found that in Tris–HCl buffer solution at pH = 8.7, energy transfer from CDs to CdTe occurred, which resulted in a great enhancement of the fluorescence intensity of CdTe. Upon the addition of chlortoluron, in terms of strong interaction between chlortoluron and CdTe QDs through the formation of chlortoluron–CdTe ground state complex, resulted in CdTe fluorescence quenching. Under optimal conditions, in range of 2.4 × 10−10 mol L−1–8.5 × 10−8 mol L−1, the change of CdTe fluorescence intensity was in good linear relationship with the chlortoluron concentration, and the detection limit was 7.8 × 10−11 mol L−1 (S/N = 3). Most of common relevant substance, cations and anions did not interfere with the detection of chlortoluron. The proposed method was applied to determine chlortoluron in water samples with satisfactory results.

Schematic illustration for the fluorescence quenching of CdTe–CDs system by chlortoluronFigure optionsDownload as PowerPoint slide