Highly sensitive and selective cartap nanosensor based on luminescence resonance energy transfer between NaYF4:Yb,Ho nanocrystals and gold nanoparticles

• Published in: Talanta (Oxford) 2013-09, Vol.114, p.124-130
• Main Authors: Wang, Zhijiang, Wu, Lina, Shen, Baozhong, Jiang, Zhaohua
• Format: Article
• Language: English
• Subjects: Beverages - analysis; Brassica - chemistry; Cartap; Chemoreceptors; detection; dyes; emissions factor; Energy Transfer; Environmental Monitoring; Excitation; farms; fluorescence; Fluorides - chemistry; Food Contamination - analysis; Fruit - chemistry; Gold; Gold - chemistry; Holmium - chemistry; insecticides; Insecticides - analysis; light intensity; Luminescence; Luminescence resonance energy transfer; Metal Nanoparticles - chemistry; Nanocomposites; Nanocomposites - chemistry; nanocrystals; nanogold; Nanomaterials; Nanosensor; Nanostructure; quantum dots; sensors (equipment); Thiocarbamates - analysis; toxic substances; Ultraviolet radiation; Upconversion nanocrystal; Ytterbium - chemistry; Yttrium - chemistry
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2013.02.069

Fluorescent detection is an attractive method for the detection of toxic chemicals. However, most chemosensors that are currently utilized in fluorescent detection are based on organic dyes or quantum dots, which suffer from instability, high background noise and interference from organic impurities in solution, which can also be excited by UV radiation. In the present research, we developed a novel NaYF4:Yb,Ho/Au nanocomposite-based chemosensor with high sensitivity (10ppb) and selectivity over competing analytes for the detection of the insecticide cartap. This nanosensor is excited with a 970-nm laser instead of UV radiation to give an emission peak at 541nm. In the presence of cartap, the nanocomposites aggregate, resulting in enhanced luminescence resonance energy transfer between the NaYF4:Yb,Ho nanocrystals and the gold nanoparticles, which decreases the emission intensity at 541nm. The relative luminescence intensity at 541nm has a linear relationship with the concentration of cartap in the solution. Based on this behavior, the developed nanosensor successfully detected cartap in farm produce and water samples with satisfactory results. A novel NaYF4:Yb,Ho/Au nanocomposite-based nanosensor was developed. This sensor can be excited with a 970-nm laser and exhibits a high selectivity over competing analytes for the detection of cartap and high sensitivity (10 ppb), far lower than the maximum level (1 ppm) of cartap in farm produce permitted by the environmental protection agencies (EPAs) of the United States and China. [Display omitted] ► A novel NaYF4:Yb,Ho/Au hybrid is fabricated by layer-by-layer assembly. ► Cartap results in luminescence resonance energy transfer between the nanosensors. ► The method exhibits good sensitivity, selectivity and accuracy.