Development of a Novel and Bi-Functional Quantum Dots as FRET Energy Donor

A novel CdTe/Ni QDs which combined both magnetism and fluorescence was successfully synthesized and its optical properties were investigated. Ni magnetic nanoparticles (MNPs) were synthesized and used as magnetic core, CdTe quantum dots (QDs) were applied as fluorescent shell material, the qualified magnetic CdTe/Ni quantum dots (mQDs) were achieved via layer-by-layer process using 1,6-hexylenediamime as linker, surface charge types of MNPs and mQDs were confirmed with a delsa nano beckman coulter. Morphology of the prepared Ni MNPs and CdTe/Ni mQDs was characterized by transmission electron microscopy (TEM), and optical properties were investigated with fluorescence spectrum (FS). Qualified CdTe/Ni mQDs with high fluorescence and narrow maximum emission peak width were obtained under the optimum conditions. Surface zeta-potential of CdTe QDs and Ni MNPs were estimated to be -36.2 and 27.97mV, respectively. TEM data indicated that ca 20nm of Ni MNPs and ca 25nm of CdTe/Ni mQDs were prepared, respectively; the size-increasing indicated the formation of CdTe shell on the Ni MNPs core. Narrow half peak width of emission peak was detected and calculated to be about 50nm via FS. High fluorescence intensity of CdTe/Ni mQDs was determined and brilliant yellow solution was observed when excited under UV360nm. The synthesized CdTe/Ni mQDs showed excellent magnetic property, and can be magnetically concentrated with a common magnet. The obtained data indicated that the prepared bi-functional CdTe/Ni mQDs possess excellent magnetic and fluorescent properties, and it can be used as a energy donor in DNA sensing based on fluorescence resonance energy transfer (FRET).

Download Full-text

DNA Detection ofToxoplasma gondiiwith a Magnetic Molecular Beacon Probe via CdTe@Ni Quantum Dots as Energy Donor

Journal of Nanomaterials ◽

10.1155/2013/473703 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6 ◽

Cited By ~ 2

Author(s):

Shichao Xu ◽

Chen Zhang ◽

Lei He ◽

Tongyao Wang ◽

Liusong Ni ◽

...

Keyword(s):

Quantum Dots ◽

Toxoplasma Gondii ◽

Molecular Beacon ◽

Resonance Energy Transfer ◽

Resonance Energy ◽

Xrd Analysis ◽

Stem Loop ◽

Current Sensing ◽

Energy Donor ◽

Base Pair Mismatch

A new method for detection ofToxoplasma gondiivia DNA sensing technology was developed in this study. It was based on the mechanism of fluorescence resonance energy transfer (FRET) in which multifunctional and magnetic-fluorescent CdTe@Ni quantum dots (mQDs) were utilized as energy donor and a commercial BHQ2as acceptor. The sensing probe was fabricated by labeling a stem-loopToxoplasma gondiiDNA oligonucleotide with CdTe@Ni mQDs at the 5′ end and BHQ2at 3′ end, respectively. The surface assembly of CdTe on Ni core and the formation of CdTe@Ni were confirmed by XRD analysis. The sizes of CdTe, Ni nanoparticles, and CdTe@Ni were measured via TEM and XRD methods and estimated to be~3 nm,~15 nm, and~20 nm, respectively. The sensing ability was investigated by the fluorescence spectrum (FS). An obvious fluorescence recovery was observed when the complete complimentary targetToxoplasma gondiiDNA was introduced, which did not happen in the case of the target DNA with one-base pair mismatch. Our research indicates that the current sensing probe is sensitive and specific in detection ofToxoplasma gondiiDNA and has great potential in Toxoplasmosis diagnosis.

Download Full-text

Optical Properties andIn VitroBiological Studies of Oligonucleotide-Modified Quantum Dots

Journal of Nanomaterials ◽

10.1155/2013/463951 ◽

2013 ◽

Vol 2013 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Valérie A. Gérard ◽

Mark Freeley ◽

Eric Defrancq ◽

Anatoly V. Fedorov ◽

Yurii K. Gun’ko

Keyword(s):

Quantum Dots ◽

Optical Properties ◽

Resonance Energy Transfer ◽

Resonance Energy ◽

Biological Imaging ◽

Water Soluble ◽

Biological Applications ◽

Potential Applications ◽

Biochemical Mechanisms

Water-soluble semiconducting nanocrystals or quantum dots (QDs) have attracted much interest in recent years due to their tuneable emission and potential applications in photonics and biological imaging. Fluorescence resonance energy transfer (FRET) processes are very important for elucidating biochemical mechanismsin vitro, and QDs constitute an excellent substrate for this purpose. In this work, new oligonucleotide-functionalised CdTe-based QDs were prepared, characterised and biologically tested. These QDs demonstrated interesting optical properties as well as remarkablein vitrobehaviour and potential for a range of biological applications.

Download Full-text

Synthesis and Characterization of the Core-Shell CdTe/ZnS Quantum Dots

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.60-61.165 ◽

2009 ◽

Vol 60-61 ◽

pp. 165-169 ◽

Cited By ~ 2

Author(s):

Shi Chao Xu ◽

Cui Cui Yao ◽

Ji Mei Zhang ◽

Zhao Dai ◽

Guo Zheng ◽

...

Keyword(s):

Quantum Dots ◽

Optical Properties ◽

Colloidal Particles ◽

Resonance Energy ◽

Quantum Yields ◽

Diagnostic Process ◽

Core Shell ◽

The Core ◽

Average Size ◽

Cdte Core

Core-shell quantum dots are colloidal particles consisting of a semiconductor core and a shell material as an outer coating layer. It can be utilized to develop sensitive methods for the detection of specific biological entities, such as microbial species, their transcription products, and single genes etc. The goal of current research is to synthesize CdTe and core-shell CdTe/ZnS quantum dots (QDs) with an improved process, and to investigate their properties. Well-dispersed CdTe core was prepared in aqueous phase with using 3-mercaptopropionic acid (MPA) as stabilizer under conditions of pH 9.1, temperature of 100 °C, refluxing for 6h, and mol ratio of Cd2+/Te2-/MPA is 1:0.5:2.4. Average size of 8 nm CdTe core was conformed via transmission electron microscopy (TEM). Core-shell CdTe/ZnS QDs were then synthesized to improve the optical properties and biocompatibility of CdTe core. Various conditions were researched to obtain the core-shell QDs with the best optical properties, such as quantum yields, fluorescence intensity etc. The results indicated that the core-shell qualified CdTe/ZnS was prepared under conditions of pH 9.0, temperature of 45 °C, refluxing for 1h, and mol ratio of CdTe/S2-/Zn2+ is 4/1/1. CdTe/ZnS with average size of 10 nm were achieved and conformed via TEM. Moreover, red shift of a maximum emission wavelength from 547 nm of CdTe to 587 of CdTe/ZnS was observed via fluorescence spectrum (FS), which inferred the growth of QDs and formation of ZnS shells. The achieved ZnS shell make CdTe core less toxic and more biocompatible, it will be useful in biological labeling, diagnostic process and biosensing system based on fluorescence resonance energy transition (FRET).

Download Full-text

Electrochemiluminescence resonance energy transfer (ERET) towards trinitrotoluene sensor based on layer-by-layer assembly of luminol-layered double hydroxides and CdTe quantum dots

Journal of Materials Chemistry C ◽

10.1039/c7tc00100b ◽

2017 ◽

Vol 5 (14) ◽

pp. 3473-3479 ◽

Cited By ~ 29

Author(s):

Zhixiong Li ◽

Yuqiong Zhou ◽

Dongpeng Yan ◽

Min Wei

Keyword(s):

Quantum Dots ◽

Energy Transfer ◽

Layered Double Hydroxides ◽

Resonance Energy Transfer ◽

Resonance Energy ◽

Cdte Quantum Dots ◽

Layer By Layer ◽

High Level ◽

Double Hydroxides ◽

Layer Assembly

Electrochemiluminescence (ECL) resonance energy transfer (ERET) systems have shown excellent potential in analysis and detection fields because of the supersensitivity, high level of controllability, and amplified signal.

Download Full-text

High-performance Förster resonance energy transfer-based dye-sensitized photocatalytic H2 evolution with graphene quantum dots as the homogeneous energy donor

Photochemical & Photobiological Sciences ◽

10.1039/c8pp00227d ◽

2018 ◽

Vol 17 (9) ◽

pp. 1147-1152 ◽

Cited By ~ 4

Author(s):

Yonggang Lei ◽

Yuan Xue ◽

Yanan Li ◽

Xiangyu Liu ◽

Fang Wang ◽

...

Keyword(s):

Quantum Dots ◽

Energy Transfer ◽

High Performance ◽

Graphene Quantum Dots ◽

Resonance Energy Transfer ◽

Resonance Energy ◽

Evolution System ◽

H2 Evolution ◽

Dye Sensitized ◽

Energy Donor

A highly efficient dye sensitized photocatalytic H2 evolution system based on Förster resonant energy transfer has been developed by employing N,S codoped graphene quantum dots as energy donor.

Download Full-text

TUNING OF EMISSION WAVELENGTH OF InAs/GaAs QUANTUM DOTS SANDWICHED BY COMBINATION LAYERS

International Journal of Nanoscience ◽

10.1142/s0219581x0600525x ◽

2006 ◽

Vol 05 (06) ◽

pp. 847-852

Author(s):

ZHIDAN FANG ◽

ZHENG GONG ◽

ZHENHUA MIAO ◽

ZHICHUAN NIU

Keyword(s):

Quantum Dots ◽

Optical Properties ◽

Buffer Layer ◽

Peak Position ◽

Emission Peak ◽

Emission Wavelength ◽

Light Sources ◽

Self Assembled

We investigate about controlling of photoluminescence (PL) wavelengths of InAs/GaAs self-assembled quantum dots (QDs) sandwiched with combination strained-buffer layer (CSBL) and combination strained-reducing layer (CSRL). The emission peak position of QDs is red-shifted to 1.37 μm. The density of the QDs is increased to 1.17 × 1010 cm -2. It is indicated that optical properties of QDs could be improved by optimizing of the buffer and covering layers for the QDs. These results may provide a new way to further developing GaAs -based 1.3 μm light sources.

Download Full-text