A ratiometric fluorescence nanoprobe using CdTe QDs for fast detection of carbaryl insecticide in apple

• Published in: Talanta (Oxford) 2021-01, Vol.221, p.121467-121467, Article 121467
• Main Authors: Shahdost-fard, F., Fahimi-Kashani, N., Hormozi-nezhad, M.R.
• Format: Article
• Language: English
• Subjects: Apple; Cadmium Compounds; Carbaryl; Carbaryl - analysis; CdTe QDs; Fluorescence; Fluorimetric sensor; Insecticide; Insecticides; Iran; Malus; Quantum Dots; Ratiometric probe; Spectrometry, Fluorescence; Tellurium
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2020.121467

In this study, a novel, simple and sensitive ratiometric fluorescence method is presented for the detection of very low quantities of the carbaryl in Iranian apple using cadmium telluride quantum dots (CdTe QDs) nanoprobe. The principle of the proposed strategy relies on the rapid hydrolysis of the carbaryl under an alkaline condition and production of the 1-naphthol with a blue emission at 470 nm. Besides, using the CdTe QDs with a yellow emission at 580 nm, as a reference, improves the visual tracking of carbaryl through changes in color tonality. The herein described methodology is applied for enzyme-free visual detection of carbaryl with satisfactory results in the presence of other common pesticides in Iranian apple sample. Additionally, the calculated limit of detection (LOD) of 0.12 ng mL−1 for carbaryl is much lower than the maximum residue limits of carbaryl warned value reported by the European Union and United States pesticides database, which is so promising for carbaryl sensing in the monitoring of fruits. Furthermore, the ability of the proposed method for the detection of carbaryl residues in Iranian apple was confirmed by the high-performance liquid chromatography (HPLC) method as a standard method through statistical analysis. This fast and highly sensitive naked-eye ratiometric sensor may hold great promise to provide the technical support for the rapid and valid detection of other targets in food safety fields. [Display omitted] •A novel and simple fluorimetric method has been presented for the fast detection of carbaryl insecticide in apple.•Rapid hydrolysis of the carbaryl under alkaline condition produces 1-naphthol with blue emission.•Yellow emissive CdTe QDs, as an internal reference, is used to design a ratiometric fluorescent nanoprobe.•Sensitive label-free detection of carbaryl displays full-spectrum color changes from yellow into green and blue.•Enzyme-free visual detection of carbaryl is readily achieved by the naked-eye with low LOD value.