Dual-Emission Fluorescence Probe Based on CdTe Quantum Dots and Rhodamine B for Visual Detection of Mercury and Its Logic Gate Behavior

It is urgent that a convenient and sensitive technique of detecting Hg2+ be developed because of its toxicity. Conventional fluorescence analysis works with a single fluorescence probe, and it often suffers from signal fluctuations which are influenced by external factors. In this research, a novel dual-emission probe assembled through utilizing CdTe quantum dots (QDs) and rhodamine B was designed to detect Hg2+ visually. Only the emission of CdTe QDs was quenched after adding Hg2+ in the dual-emission probe, which caused an intensity ratio change of the two different emission wavelengths and hence facilitated the visual detection of Hg2+. Compared to single emission QDs-based probe, a better linear relationship was shown between the variation of fluorescence intensity and the concentration of Hg2+, and the limit of detection (LOD) was found to be11.4 nM in the range of 0–2.6 μM. Interestingly, the intensity of the probe containing Hg2+ could be recovered in presence of glutathione (GSH) due to the stronger binding affinity of Hg2+ towards GSH than that towards CdTe QDs. Based on this phenomenon, an IMPLICATION logic gate using Hg2+/GSH as inputs and the fluorescence signal of QDs as an output was constructed.

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Sensitive detection of tamsulosin hydrochloride based on dual-emission ratiometric fluorescence probe consisting of amine-carbon quantum dots and rhodamine B

Scientific Reports ◽

10.1038/s41598-021-00363-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Aida Mousavi ◽

Rouholah Zare-Dorabei ◽

Seyed Hossein Mosavi

Keyword(s):

Quantum Dots ◽

Rhodamine B ◽

Fluorescence Probe ◽

Limit Of Detection ◽

Biological Fluids ◽

Specific Interaction ◽

Carbon Quantum Dots ◽

Dual Emission ◽

Selective Determination ◽

The One

AbstractIn this work, amine-carbon quantum dots (CQDs)/rhodamine B (RhB) ratiometric fluorescent (RF) sensor was employed for effective and selective determination of tamsulosin hydrochloride (TMS) based on a dual-emission fluorescence system. Although the function of amine-CQDs is to transfer the specific interaction between TMS and sensor into detectable fluorescence (FL) signals, RhB as a reference unit has been employed to omit internal and external effects. The FL signal was quenched by adding the TMS at 442 nm; nevertheless, it did not change at 569 nm. The material characterization and investigation of the sensing mechanism were done. The optimization of pH, the volumetric ratio of CQDs to RhB, and interaction time parameters were carried out by the one-variable-at-a-time (OVAT) method. The quantitative analysis of the concentration of TMS for this RF sensor in a linear range of 0.446–7.083 μg mL−1 (1.091–17.338 μM) was obtained (R2 = 0.9969, n = 3) under optimum conditions. The limit of detection and quantitation values were estimated to be 0.033 μg mL−1 (0.081 μM) and 0.109 μg mL−1 (0.267 μM), respectively. The repeatability of intra-day and inter-day were less than one percent. This inexpensive RF probe was well applied to determine TMS in biological fluids, and acceptable achievements were obtained.

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Facile Synthesis and Properties of Aqueous CdTe Quantum Dots for High-Sensitive Copper (II) Ion Detection

NANO ◽

10.1142/s179329201750151x ◽

2017 ◽

Vol 12 (12) ◽

pp. 1750151 ◽

Cited By ~ 1

Author(s):

Yue Zheng ◽

Hengshan Tang ◽

Xiaoyu Wang ◽

Ya Di ◽

Kunling Lu ◽

...

Keyword(s):

Quantum Dots ◽

Limit Of Detection ◽

Tap Water ◽

High Sensitivity ◽

Cdte Quantum Dots ◽

Reaction Conditions ◽

One Pot ◽

Sensing System ◽

Cdte Qds ◽

Transmission Electron

The synthesis of aqueous MPA-capped CdTe quantum dots (QDs) via a facile one-pot route was developed. The particle size, optical properties and crystal structure of the as-synthesis QDs were investigated by transmission electron microscopy (TEM), Fourier transform infrared (FTIR), UV-vis absorption and photoluminescence (PL) spectra, respectively. Meanwhile, the effect of reaction conditions, including reaction time, pH and the quantity of sodium citrate (SC) on the growth of CdTe QDs were discussed. Then, the obtained CdTe QDs were successfully used for the detection of trace Cu[Formula: see text] with high sensitivity and excellent selectivity. The fluorescence intensity of CdTe QDs with Cu[Formula: see text] concentration showed a linear relationship in the range from [Formula: see text] mol/L to [Formula: see text][Formula: see text]mol/L. The correlation coefficient (R) is 0.9980 and limit of detection (LOD) is [Formula: see text][Formula: see text]mol/L. Moreover, the concentration of Cu[Formula: see text] in tap water samples was determined based on this sensing system and the recovery test was satisfactory.

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Sensitive Ratiometric Probing of Tamsulosin Hydrochloride Based On Dual-Emission Fluorescent In Biological Fluids Utilizing Amine-Carbon Quantum Dots And Rhodamine B

10.21203/rs.3.rs-557370/v1 ◽

2021 ◽

Author(s):

Aida Mousavi ◽

Rouholah Zare-Dorabei ◽

Seyed Hossein Mosavi

Keyword(s):

Quantum Dots ◽

Rhodamine B ◽

Limit Of Detection ◽

Biological Fluids ◽

Specific Interaction ◽

Carbon Quantum Dots ◽

Dual Emission ◽

Selective Determination ◽

Ft Ir ◽

The One

Abstract In this work, amine-carbon quantum dots (CQDs)/rhodamine B (RhB) ratiometric fluorescent (RF) sensor was employed for effective and selective determination of tamsulosin hydrochloride (TMS) based on a dual-emission fluorescence system. Although the function of amine-CQDs is to transfer the specific interaction between TMS and sensor into detectable fluorescence (FL) signals, RhB as a reference unit has been employed to omit internal and external effects. The FL signal was quenched by adding the TMS at 442nm; nevertheless, it did not change at 569nm. The material characterization and investigation of the sensing mechanism were done by UV-Vis, fluorimetry, EDS, TEM, FT-IR, and zeta potential analyses. The optimization of pH, the volumetric ratio of CQDs to RhB, and interaction time parameters were carried out by the one-variable-at-a-time (OVAT) method. The quantitative analysis of the concentration of TMS for this RF sensor in a linear range of 0.446-7.083 μg mL-1 was obtained (R2=0.9969, n=3) under optimum conditions. The limit of detection and quantitation values were estimated to be 0.033 μg mL-1 and 0.109 μg mL-1, respectively. Repeatability of intra-day and inter-day were less than one percent. This inexpensive RF probe was well applied to determine TMS in biological fluids, and acceptable achievements were obtained.

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Copper ion-induced fluorescence band shift of CdTe quantum dots: a highly specific strategy for visual detection of Cu2+ with a portable UV lamp

The Analyst ◽

10.1039/c5an01963j ◽

2015 ◽

Vol 140 (23) ◽

pp. 7859-7863 ◽

Cited By ~ 8

Author(s):

Xiaohui Lu ◽

Yunjie Zhao ◽

Jinjun Zhang ◽

Xiaozhen Lu ◽

Yucong Wang ◽

...

Keyword(s):

Quantum Dots ◽

Visual Detection ◽

Copper Ion ◽

Cdte Quantum Dots ◽

Fluorescence Band ◽

Intensity Change ◽

Band Shift ◽

Specific Strategy ◽

Cdte Qds ◽

Uv Lamp

Visual detection of Cu2+ is realized based on a copper-induced fluorescence band shift rather than an intensity change of CdTe QDs.

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Novel “turn on–off” paper sensor based on nonionic conjugated polythiophene-coated CdTe QDs for efficient visual detection of cholinesterase activity

The Analyst ◽

10.1039/d0an00924e ◽

2020 ◽

Vol 145 (12) ◽

pp. 4305-4313 ◽

Cited By ~ 1

Author(s):

Qi Ou ◽

Salah M. Tawfik ◽

Xinfeng Zhang ◽

Yong-Ill Lee

Keyword(s):

Quantum Dots ◽

Ache Activity ◽

Cholinesterase Activity ◽

Visual Detection ◽

Color Variation ◽

Cdte Quantum Dots ◽

Turn On ◽

Cdte Qds ◽

Paper Sensor

A novel conjugated polythiophene (CP) compound was successfully combined with CdTe quantum dots to improve their selectivity and sensitivity for the efficient visual detection of AChE activity via the color variation of CdTe/CP.

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Electrostatic repulsion strategy for highly selective and sensitive “switch–on” fluorescence sensor of ascorbic acid based on the cysteamine-coated CdTe quantum dots and cerium (IV)

New Journal of Chemistry ◽

10.1039/d1nj00145k ◽

2021 ◽

Author(s):

Yifei Guo ◽

Jingjing Du ◽

Jianjun Li ◽

Ran Yang ◽

Peter B. de Harrington ◽

...

Keyword(s):

Quantum Dots ◽

Ascorbic Acid ◽

Hydrothermal Method ◽

Cadmium Chloride ◽

Fluorescence Sensor ◽

Cdte Quantum Dots ◽

Electrostatic Repulsion ◽

Functional Monomer ◽

Simple Hydrothermal Method ◽

Cdte Qds

In this work, cysteamine-coated CdTe quantum dots (CA-CdTe QDs) were synthesized by a simple hydrothermal method employing cadmium chloride as the cadmium source and cysteamine hydrochloride as the functional monomer....

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