Rapid determination of melamine in milk using water-soluble CdTe quantum dots as fluorescence probes

A simple A green protocol for synthesis of high quality, water-soluble and biocompatible CdS QDs have been developed in aqueous solution with amylum as stabilizing agent. The QDs were characterized by AMF and spectral methods. A fluorescence quenching method was developed for determination of iron (ΙΙΙ) with water soluble CdS quantum dots (QDs) as fluorescence probe. In pH 8.5 boric acid–borax buffer solution, the QDs show a high selective to ferric ion. The common cations, such as Ca2+, Mg2+, Zn2+, Fe2+ et al, have no effect on interference but copper ion. The fluorescence intensity of the QDs decreased linearly with the iron (QDs ) concentration in the range of 200 μM to 60 nM with a detection limit of 20 nM. It has been applied to determinate of iron in Angelica, Astragalus, Shouwu, ligusticum wallichii and radix rehmanniae recen.

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The selective deprotonation of carbon quantum dots for fluorescent detection of phosphate and visualization of latent fingerprints

Nanoscale ◽

10.1039/d1nr02432a ◽

2021 ◽

Author(s):

Li Yang ◽

Qi Zhang ◽

Ying Han ◽

Hongjuan Li ◽

Shiguo Sun ◽

...

Keyword(s):

Quantum Dots ◽

Rapid Determination ◽

Carbon Quantum Dots ◽

Water Soluble ◽

Fluorescent Detection ◽

Latent Fingerprints ◽

Fluorescent Sensing ◽

Turn On ◽

Sensing Platform

We developed a water-soluble, stable and selective “turn-on” fluorescent sensing platform based on carbon quantum dots (CQDs) for rapid determination of the phosphate (Pi) in aqueous solutions and visualization of...

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Determination of particle size distribution of water-soluble CdTe quantum dots by optical spectroscopy

RSC Advances ◽

10.1039/c4ra05979d ◽

2014 ◽

Vol 4 (68) ◽

pp. 36024-36030 ◽

Cited By ~ 14

Author(s):

J. C. L. Sousa ◽

M. G. Vivas ◽

J. L. Ferrari ◽

C. R. Mendonca ◽

M. A. Schiavon

Keyword(s):

Quantum Dots ◽

Particle Size ◽

Optical Properties ◽

Particle Size Distribution ◽

Size Distribution ◽

Water Soluble ◽

Cdte Quantum Dots ◽

One Pot ◽

The One

In the present study, we report the synthesis of glutathione (GSH) capped CdTe quantum dots (QDs) using the one-pot approach as well as their optical properties.

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Rapid determination of malachite green in water and fish using a fluorescent probe based on CdTe quantum dots coated with molecularly imprinted polymer

Sensors and Actuators B Chemical ◽

10.1016/j.snb.2016.07.166 ◽

2017 ◽

Vol 239 ◽

pp. 69-75 ◽

Cited By ~ 49

Author(s):

Le Wu ◽

Zheng-zhong Lin ◽

Hui-ping Zhong ◽

Xiao-mei Chen ◽

Zhi-yong Huang

Keyword(s):

Quantum Dots ◽

Fluorescent Probe ◽

Malachite Green ◽

Molecularly Imprinted Polymer ◽

Rapid Determination ◽

Cdte Quantum Dots ◽

Imprinted Polymer ◽

Molecularly Imprinted

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CdTe Quantum Dots Modified with Cysteamine: A New Efficient Nanosensor for the Determination of Folic Acid

Sensors ◽

10.3390/s19204548 ◽

2019 ◽

Vol 19 (20) ◽

pp. 4548 ◽

Cited By ~ 3

Author(s):

Doris E. Ramírez-Herrera ◽

Ana Patricia Reyes-Cruzaley ◽

Giselle Dominguez ◽

Francisco Paraguay-Delgado ◽

Antonio Tirado-Guízar ◽

...

Keyword(s):

Quantum Dots ◽

Folic Acid ◽

Fluorescence Quenching ◽

Low Cost ◽

Water Soluble ◽

Cdte Quantum Dots ◽

Photoluminescence Intensity ◽

Beverage Samples ◽

Cdte Qds

In this paper, we report the synthesis, characterization, and application of a new fluorescent nanosensor based on water-soluble CdTe quantum dots (QDs) coated with cysteamine (CA) for the determination of folic acid (FA). CdTe/CA QDs were characterized by high-resolution transmission electron microscopy, the zeta potential, and Fourier-transform infrared (FT-IR), UV-visible, and fluorescence spectroscopy. CdTe QDs coated with mercaptopropionic acid (MPA) and glutathione (GSH) were prepared for comparison purposes. The effect of FA on the photoluminescence intensity of the three thiol-capped QDs at pH 8 was studied. Only CdTe/CA QDs showed a notable fluorescence quenching in the presence of FA. Then, a nanosensor based on the fluorescence quenching of the CdTe QDs at pH 8 was explored. Under optimum conditions, the calibration curve showed a linear fluorescence quenching response in a concentration range of FA from 0.16 to 16.4 μM (R2 = 0.9944), with a detection limit of 0.048 μM. A probable mechanism of fluorescence quenching was proposed. The nanosensor showed good selectivity over other possible interferences. This method has been applied for FA quantification in orange beverage samples with excellent results (recoveries from 98.3 to 103.9%). The good selectivity, sensitivity, low cost, and rapidity make CdTe /CA QDs a suitable nanosensor for FA determination.

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