Fluorescence enhancement of CdTe/CdS quantum dots by coupling of glyphosate and its application for sensitive detection of copper ion

• Published in: Analytica chimica acta 2012-10, Vol.745, p.78-84
• Main Authors: Liu, Zhengqing, Liu, Shaopu, Yin, Pengfei, He, Youqiu
• Format: Article
• Language: English
• Subjects: Analytical chemistry; Applied sciences; Cadmium Compounds - chemistry; Chemistry; Copper - analysis; Copper ion; Environmental Monitoring - methods; Exact sciences and technology; Fluorescence; Fluorescent Dyes - chemistry; Global environmental pollution; Glycine - analogs & derivatives; Glycine - chemistry; Glyphosate; Ions - analysis; Limit of Detection; Microscopy, Electron, Transmission; Molecular Probe Techniques; Pollution; Probe; Quantum Dots; Sensitivity and Specificity; Spectrometric and optical methods; Sulfides - chemistry; Tellurium - chemistry; Thioglycolates - chemistry; Wastewater - chemistry
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2012.07.033

Glyphosate (Glyp) had been used to modify the surface of CdTe/CdS QDs, resulting in the enhancement of fluorescence intensity. The Glyp-functionalized QDs fluorescent probe offers good sensitivity and selectivity for detecting Cu2+ based on the fluorescence quenching. [Display omitted] ► Water soluble CdTe/CdS quantum dots capped with glyphosate were firstly synthesized. ► The fluorescence of the Glyp-functionalized QDs was quenched by copper ion. ► A new fluorescent sensor for copper ion was developed based on the prepared QDs. ► The sensor exhibited high sensitivity and good selectivity for copper ion. A novel fluorescent probe for Cu2+ determination based on the fluorescence quenching of glyphosate (Glyp)-functionalized quantum dots (QDs) was firstly reported. Glyp had been used to modify the surface of QDs to form Glyp-functionalized QDs following the capping of thioglycolic acid on the core–shell CdTe/CdS QDs. Under the optimal conditions, the response was linearly proportional to the concentration of Cu2+ between 2.4×10−2μgmL−1 and 28μgmL−1, with a detection limit of 1.3×10−3μgmL−1 (3δ). The Glyp-functionalized QDs fluorescent probe offers good sensitivity and selectivity for detecting Cu2+. The fluorescent probe was successfully used for the determination of Cu2+ in environmental samples. The mechanism of reaction was also discussed.