In-Situ Preparation of CdTe Quantum Dots Capped with a β-Cyclodextrin-Epichlorohydrin Polymer: Polymer Influence on the Nanocrystal’s Optical Properties

β-Cyclodextrin (βCD), the less water soluble of the cyclodextrins, has been used as a capping agent in the preparation of semiconductor nanocrystals or quantum dots (QDs). Nevertheless, no reports have been found in the use of the highly water-soluble polymer of this, prepared by the crosslinking of the βCD units with epichlorohydrin in basic medium (βCDP). This polymer, besides to overcome the low solubility of the βCD, increases the inclusion constant of the guest; two parameters that deserve its use as capping agent, instead of the native cyclodextrin. In the present manuscript, we afforded the in-situ aqueous preparation of cadmium telluride (CdTe) QDs capped with βCDP. The polymer influence on the photoluminescent properties of the nanocrystals was analyzed. The βCDP controls the nanocrystals growth during the Oswald ripening stage. Consequently, the CdTe capped βCDP QDs showed lower Stokes-shift values, higher photoluminescent efficiency, and narrower size distribution than for nanocrystals obtained in the absence of polymer. Transmission electron microscopy (TEM) micrographs and energy dispersive X-ray spectroscopy (EDS) analysis revealed the composition and crystallinity of the CdTe QDs. This βCDP capped CdTe QDs is a potential scaffold for the supramolecular modification of QDs surface.

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UV-light-actuated in-situ preparation of paper@ZnCd quantum dots for paper-based enzymatic nanoreactors

Chemical Engineering Journal ◽

10.1016/j.cej.2021.132508 ◽

2021 ◽

pp. 132508

Author(s):

Nichakan Khunkitchai ◽

Nantana Nuchtavorn ◽

Tomas Rypar ◽

Marcela Vlcnovska ◽

Lukas Nejdl ◽

...

Keyword(s):

Quantum Dots ◽

Uv Light ◽

In Situ Preparation

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In situ preparation of fluorescent CdTe quantum dots with small thiols and hyperbranched polymers as co-stabilizers

Nanoscale Research Letters ◽

10.1186/1556-276x-9-121 ◽

2014 ◽

Vol 9 (1) ◽

Cited By ~ 4

Author(s):

Yunfeng Shi ◽

Zhimin Ma ◽

Ningning Cui ◽

Yanli Liu ◽

Xiaoyu Hou ◽

...

Keyword(s):

Quantum Dots ◽

Hyperbranched Polymers ◽

Cdte Quantum Dots ◽

In Situ Preparation

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DNA-Based Assembly of Quantum Dots into Dimers and Helices

Nanomaterials ◽

10.3390/nano9030339 ◽

2019 ◽

Vol 9 (3) ◽

pp. 339 ◽

Cited By ~ 4

Author(s):

Tao Zhang ◽

Tim Liedl

Keyword(s):

Quantum Dots ◽

Colloidal Stability ◽

Water Soluble ◽

Special Equipment ◽

Plastic Tube ◽

Dna Templates ◽

Fluorescent Markers ◽

Direct Attachment ◽

Conjugation Method

Owing to their unique optical properties, colloidal quantum dots (QDs) have attracted much attention as versatile fluorescent markers with broad biological and physical applications. On the other hand, DNA-based assembly has proven to be a powerful bottom-up approach to create designer nanoscale objects and to use these objects for the site-directed arrangement of guest components. To achieve good colloidal stability and accurate positioning of QDs on DNA templates, robust QD surface functionalization is crucial. Here, we present a simple and reliable conjugation method for the direct attachment of DNA molecules to QDs. Phosphorothiolated regions of chimera oligonucleotides are attached and incorporated into a ZnS layer freshly growing in situ on QDs that were rendered water soluble with hydrophilic ligands in a prior step. The reaction can be completed in a 2 mL plastic tube without any special equipment. The utility of these DNA-labeled QDs is demonstrated via prototypical assemblies such as QDs dimers with various spacings and chiral helical architectures.

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Polyaniline: Thin films and colloidal dispersions (IUPAC Technical Report)

Pure and Applied Chemistry ◽

10.1351/pac200577050815 ◽

2005 ◽

Vol 77 (5) ◽

pp. 815-826 ◽

Cited By ~ 178

Author(s):

Jaroslav Stejskal ◽

Irina Sapurina

Keyword(s):

Thin Films ◽

Dispersion Polymerization ◽

Average Particle Size ◽

Colloidal Dispersions ◽

Water Soluble ◽

Average Particle ◽

Water Soluble Polymer ◽

Ammonium Peroxydisulfate ◽

Technical Report

Several workers from various institutions in six countries have prepared thin films and colloidal polyaniline dispersions. The films were produced in situ on glass supports during the oxidation of anilinium chloride with ammonium peroxydisulfate in water. The average thickness of the films, assessed by optical absorption, was 125 ± 9 nm, and the conductivity of films was 2.6 ± 0.7 S cm–1. Films prepared in 1 mol l–1 HCl had a similar thickness, 109 ± 10 nm, but a higher conductivity, 18.8 ± 7.1 S cm–1. Colloidal polyaniline particles stabilized with a water-soluble polymer, poly(N-vinylpyrrolidone) [poly(1-vinylpyrrolidin-2-one)], have been prepared by dispersion polymerization. The average particle size, 241 ± 50 nm, and polydispersity, 0.26 ± 0.12, have been determined by dynamic light scattering. The preparation of these two supramolecular polyaniline forms was found to be well reproducible.

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Synthesis of Fluorescent CdS Quantum Dots of Tunable Light Emission with a New in Situ Produced Capping Agent

Industrial & Engineering Chemistry Research ◽

10.1021/ie201826e ◽

2012 ◽

Vol 51 (17) ◽

pp. 5995-6000 ◽

Cited By ~ 25

Author(s):

Yan-mei Mo ◽

Yu Tang ◽

Fei Gao ◽

Jun Yang ◽

Yuan-ming Zhang*

Keyword(s):

Quantum Dots ◽

Light Emission ◽

Capping Agent ◽

Cds Quantum Dots

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In Situ Preparation of Amphibious ZnO Quantum Dots with Blue Fluorescence Based on Hyperbranched Polymers and their Application in Bio-Imaging

Polymers ◽

10.3390/polym12010144 ◽

2020 ◽

Vol 12 (1) ◽

pp. 144 ◽

Cited By ~ 1

Author(s):

Gaiying Lei ◽

Shu Yang ◽

Ranran Cao ◽

Peng Zhou ◽

Han Peng ◽

...

Keyword(s):

Quantum Dots ◽

Gene Transfection ◽

Heating Time ◽

Water Soluble ◽

Molar Ratio ◽

Quantum Yields ◽

Blue Fluorescence ◽

In Situ Preparation ◽

Bio Imaging ◽

Zno Quantum Dots

A new strategy for preparing amphibious ZnO quantum dots (QDs) with blue fluorescence within hyper-branched poly(ethylenimine)s (HPEI) was proposed in this paper. By changing [Zn2+]/[OH−] molar ratio and heating time, ZnO QDs with a quantum yields (QY) of 30% in ethanol were obtained. Benefiting from the amphibious property of HPEI, the ZnO/HPEI nanocomposites in ethanol could be dissolved in chloroform and water, acquiring a QY of 53%, chloroform and 11% in water. By this strategy, the ZnO/HPEI nano-composites could be applied in not only in optoelectronics, but also biomedical fields (such as bio-imaging and gene transfection). The bio-imaging application of water-soluble ZnO/HPEI nanocomposites was investigated and it was found that they could easily be endocytosed by the COS-7 cells, without transfection reagent, and they exhibited excellent biological imaging behavior.

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