JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
·
2020
·Vol. 20
·期 9
·5478-5485
·
IF 1.134
Xie Cong,Zhao Yubin,Song Yuxiang,Liu Yingjie,Wang Yaya,Yang Ping
Compared with conventional semiconductor quantum dots, hybrid SiO2 coated CdTe QDs exhibited high stability, long fluorescent lifetime, high photoluminescence quantum yields, and well biocompatibility. In this paper, CdTe QDs with tunable PL from green to red emitting were
prepared by an aqueous synthesis. A sol–gel process resulted in CdTe QDs coated with a hybrid SiO2 shell contained CdS-like clusters to obtain red-shifted PL spectra, increased PL efficiency and high stability. The clusters were formed by the reaction of Cd2+ and
S2− ions generated via the decomposition of thioglycolic acid. The clusters around CdTe cores created a core–shell structure which is very similar with traditional semiconductor core–shell QDs. After being coated with a hybrid SiO2 shell, the PL of green-emitting
naked CdTe QDs was red-shifted largely (~30 nm) while the PL of yellowemitting CdTe QDs revealed a small red-shifted (~20 nm). Furthermore, The PL of red-emitting naked CdTe QDs was red-shifted much small (less than 10 nm). This phenomenon is ascribed to the change of band gap of CdTe cores
with sizes. The red-shift of PL spectra is attributed to the CdS-like clusters around the core rather than the thickness of the hybrid SiO2 shell.
研究领域:
材料科学
·
纳米技术
·
光学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF LUMINESCENCE
·
2011
·
IF 1.797
Jinyun Peng,Xiaoya Hu
A new method for the determination of roxithromycin based on the fluorescence quenching of 3-mercaptopropionic acid-capped CdTe quantum dots (MPA-CdTe QDs) was developed. In ethanol medium, the fluorescence of CdTe quantum dots at 552 nm was quenched in the presence of roxithromycin. Based on this a simple, sensitive, and selective method for rapid determination of roxithromycin was described. Reaction time, interfering substances on the fluorescence quenching, and mechanism of the interaction of CdTe QDs with roxithromycin were investigated. After optimization, the proposed method allows the determination of roxithromycin over the range 25.0–350.0 μg ml −1 . The detection limit is 4.6 μg ml −1 . The proposed method was successfully applied to commercial capsules and tablets with satisfactory results. The recovery of the method was in the range of 96.8–102.5%.
研究领域:
分析化学
·
药学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CRYSTAL GROWTH
·
2025
·
IF 2
Van-Thao Ta,Duy-Khanh Nguyen,Xuan-Bach Nguyen,Phuong-Nam Nguyen,Sinh-Hung Nguyen,Xuan-Dung Mai
The development of a simple, cost-effective, and green method to synthesize CdTe quantum dots (QDs), which are a key nanomaterial in sensing, bioimaging, and immunofluorescence analysis is highly desirable. In this study, we used ammonia in lieu of common hydride reductant to synthesize CdTe QDs by simple refluxing aqueous solutions of cadmium salt, sodium tellurite, and 3-mercaptopropionic acid (MPA). The obtained CdTe QDs were characterized by absorption and photoluminescent spectroscopies, X-ray diffraction (XRD), and transmission electron microscope (TEM). The absorption window and the emission color of QDs were facile controlled over the green–red range by varying the refluxing time. As the QD size increased the crystal structure transformed from CdTe to a CdTeS alloyed form. The results demonstrated herein suggest a cost-effective method for production of CdTe QDs.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
Yuting Wang,Jia Liu,Bin Yang,Fengming Zhang,Xin Liu,Shiyue Niu,Shuyun Bi
Based on the fluorescence sensor of 3-Mercaptopropionic acid (MPA) capped CdTe quantum dots (QDs), two novel detection methods for aklomide and nitromide were developed. The MPA-CdTe QDs were synthesized and characterized by transmission electron microscopy (TEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), ultraviolet visible (UV–vis) and fluorescence (FL). The quenchings were all static. The binding constants ( K a ) at different temperatures were obtained. Electrostatic forces were the main forces for the two bindings. For the detection of aklomide and nitromide, under the optimal conditions, the effects of some metal ions, glucose, bovine serum albumin (BSA) and congeneric drug on the determination were explored. The standard equations were established and the limits of detection (LOD) were 0.0215 and 0.0388 μg mL −1 (3 S 0 / S ), repectively. The methods were applied to analyse the samples of chicken and duck, the recoveries were 99.41 % – 101.24 % with RSDs of 0.29 % – 1.19 % ( n = 5).
研究领域:
分析化学
·
食品科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 47
·24612-24618
·
IF 3.708
Yangyang Li,Ben Q. Li
An optical-thermal experimental system, in which CdTe quantum dots (QDs) were used as thermal sensors, is developed for micro-electromechanical system (MEMS) temperature measurements in the high temperature range (>70 °C). Laboratory-prepared CdTe QDs with suitably controlled synthesis conditions show excellent temperature sensitivity. For orange emitting CdTe QDs, calibration from a type A micro-heater yields a linear relation between the spectral peak shift and the temperature over the temperature range of 27 °C to 170 °C, the last being the highest temperature of the heater achieved in our current optical-thermal experimental setup. This linear relation is consistent with the predictions for semiconductor quantum systems from the principle of thermo-quantum mechanics for the temperature above the Debye point. Analysis of the experimental data indicates that the orange emitting QDs possess a thermally-induced spectral-shift sensitivity of 0.34 nm °C−1, which is approximately about 2–3 times better than reported. The excellent repeatability and accuracy of the calibrated orange emitting CdTe QDs as thermal sensors are further demonstrated by applying them in monitoring electric thermal characteristics of type B MEMS structures. While calibration is for up to 170 °C, the temperature of up to 212 °C for the type B MEMS heater was measured with a satisfactory accuracy using the CdTe QDs, further demonstrating the stability of the thermal-spectral properties of the QDs. The existence of a unique “burnout” spectrum in the temperature dependent PL spectra also suggests that optical-thermally sensitive QDs can be applied in both monitoring the temperature development and diagnosing circuit breakout due to over-heating.
研究领域:
材料科学
·
光学工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
·
2019
·Vol. 19
·期 7
·4310-4314
·
IF 1.093
Zhao Yue,Jiang Zhixiang,Wang Tao,Song Tong,Li Juping,Yang Ping
The stability of quantum dots (QDs) in phosphate buffered saline (PBS) solutions plays an important role in the bio-applications. Red-emitting CdTe QDs with high PL efficiency were prepared using thiogliycolic acid as a capping agent. The assembly of the QDs in various buffer components
was investigated. Using buffer components such as NaCl, KCl, and phosphate salts as scaffolds, the assembly of CdTe QDs occurred on a slide glass in the re-crystalline process of buffer components. The QDs were homogeneously assembled into the composites with leaf or flake shapes. The result
is utilizable for pattern manufacture in applications and domain growth was developed to test the change of photoluminescence (PL) properties and self-assembly of the QDs to form fractal structures. Compared with initial CdTe QD solutions, the PL spectrum of the QDs in the composite is narrowed.
The stability test indicated that H2PO−
4 and HPO2−
4 ions play important roles to decrease the PL of the QDs in PBS buffer solvents.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
DOI
PubMed
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 90
·48967-48972
·
IF 3.708
Yan Liang,Jiawei Tan,Jiexin Wang,Jianfeng Chen,Baochang Sun,Lei Shao
The effects of erythorbic acid (EA) and ethanol on the aqueous formation of cadmium telluride (CdTe) quantum dots (QDs) were explored in this work. Without N2 protection, CdTe QDs were synthesized with cadmium chloride and sodium hydrogen telluride as the Cd source and Te source, respectively, together with EA and with 3-mercaptopropionic acid (MPA) as the co-passivating ligand. The experimental results indicated that the use of the oxygen scavenger, i.e., EA, was critical for the formation of the CdTe QDs with reasonably good optical properties. Including ethanol during the synthesis improved the photoluminescence intensity. To attain good optical properties, it is also important to tune experimental parameters such as pH, temperature, reaction time, molar ratio of MPA/Cd, and sodium borohydride dosage. The very reason that EA promoted formation of CdTe QDs is because of its reducibility and passivation on the QD surface. The present study suggests that the use of EA and ethanol could be a practical means to promote the photoluminescence of CdTe.
研究领域:
材料科学
·
纳米技术
✓ 已验证
DOI
高影响因子
BULLETIN OF THE CHEMICAL SOCIETY OF ETHIOPIA
·
2013
·Vol. 27
·期 3
·387-393
·
IF 0.417
Y. Wang,R. Wang,S. Liu,K. Yang,L. Zhou,H. Li
L-Cysteine (Cys)-capped CdTe quantum dots (QDs) were prepared when sodium tellurite worked as a tellurium source and sodium borohydride acted as a reductant. The influences of various experimental variables, including pH values, Cd/Te and Cd/Cys molar ratios, on the photoluminescence (PL) quantum yield (QY) of the obtained CdTe QDs have been systematically investigated. Experimental results indicated that green to red emitting CdTe QDs with maximum quantum yield of 19.4% can be prepared at pH 11.5 and n(Cd2+):n(Te2−):n(Cys) = 1:0.07:2.0. X-Ray powder diffraction (XRD) and transmission electron microscopy (TEM) were used to characterize the crystal structure and shape of CdTe QDs. The results showed that the prepared CdTe QDs were of cubic zinc blend crystal structure in a sphere-like shape. KEY WORDS: Semicondutor nanocrystal, Chemical synthesis, Optical properties, Luminescence Bull. Chem. Soc. Ethiop. 2013, 27(3), 387-393.DOI: http://dx.doi.org/10.4314/bcse.v27i3.7
研究领域:
材料科学
·
化学合成
·
光学性质
✓ 已验证
DOI
高影响因子
LUMINESCENCE
·
2012
·Vol. 28
·期 3
·259-264
·
IF 1.731
Zhonghui Wang,Hongjie Song,Huihui Zhao,Yi Lv
Electrogenerated chemiluminescence (ECL) of thiol-capped CdTe quantum dots (QDs) in aqueous solution was greatly enhanced by PDDA-protected graphene (P-GR) film that were used for the sensitive detection of H 2 O 2 . When the potential was cycled between 0 and −2.3 V, two ECL peaks were observed at −1.1 (ECL-1) and −1.4 V (ECL-2) in pH 11.0, 0.1 M phosphate buffer solution (PBS), respectively. The electron-transfer reaction between individual electrochemically-reduced CdTe nanocrystal species and oxidant coreactants (H 2 O 2 or reduced dissolved oxygen) led to the production of ECL-1. While mass nanocrystals packed densely in the film were reduced electrochemically, assembly of reduced nanocrystal species reacted with coreactants to produce an ECL-2 signal. ECL-1 showed higher sensitivity for the detection of H 2 O 2 concentrations than that of ECL-2. Further, P-GR film not only enhanced ECL intensity of CdTe QDs but also decreased its onset potential. Thus, a novel CdTe QDs ECL sensor was developed for sensing H 2 O 2 . Light intensity was linearly proportional to the concentration of H 2 O 2 between 1.0 × 10 −5 and 2.0 x 10 -7 mol L −1 with a detection limit of 9.8 x 10 −8 mol L −1 . The P-GR thin-film modified glassy carbon electrode (GCE) displayed acceptable reproducibility and long-term stability. Copyright © 2012 John Wiley & Sons, Ltd.
研究领域:
分析化学
·
生物传感
✓ 已验证
DOI
PubMed
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2012
·
IF 2.098
Ting-Ting Gan,Yu-Jun Zhang,Nan-Jing Zhao,Xue Xiao,Gao-Fang Yin,Shao-Hui Yu,Huan-Bo Wang,Jing-Bo Duan,Chao-Yi Shi,Wen-Qing Liu
Mercaptopropionic acid (MPA) capped CdTe quantum dots (QDs) with particle size 3 nm have been successfully synthesized in aqueous medium by hydrothermal synthesis method. And the effects of different metal ions on MPA capped CdTe QDs fluorescence were studied using fluorescence spectrometry. The results demonstrated that at the same concentration level, Ag + could strongly quench CdTe QDs fluorescence, and the other metal ions had little effect on CdTe QDs fluorescence except Cu 2+ . On the basis of this fact, a rapid, simple, highly sensitive and selective method based on fluorescence quenching principle for Ag + detection in aqueous solution was proposed. Under optimal conditions, the quenched fluorescence intensity ( F 0 – F ) increased linearly with the concentration of Ag + ranging from 4 × 10 −7 to 32 × 10 −7 mol L −1 . The limit of detection for Ag + was 4.106 × 10 −8 mol L −1 . The obtained plot of F 0 / F versus [Ag + ] was an upward curvature, concave towards the y -axis, rather than a straight line. The modified form of the Stern–Volmer equation was third order in Ag + concentration. According to the modified Stern–Volmer equation, it can be inferred that dynamic quenching and static quenching simultaneously occurred when Ag + interacted with MPA capped CdTe QDs. At the same time other factors might also influence the quenching process. Based on this study, hydrothermal synthesized MPA capped CdTe QDs with particle size 3 nm may be used as a novel fluorescence probe to quantificationally and selectively detect Ag + .
研究领域:
分析化学
·
纳米材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Analysis and Testing
·
2017
·Vol. 2
·期 1
·90-97
·
IF 0
Wang Zhong-Xia,Li Qi-Le,Kong Fen-Ying,Wang Wei,Ding Shou-Nian
In this paper, dual-stabilizer-capped CdTe quantum dots were used as modulated photoluminescence (PL) sensors for the subpicomolar level detection of copper(II) (Cu 2+ ) and mercury(II) (Hg 2+ ) ions in aqueous solution for the first time. The dual-stabilizer-capped CdTe quantum dots were synthesized using mercaptopropionic acid (MPA) and sodium hexametaphosphate (SHMP) as surface-modified ligands via a convenient hydrothermal process. The researches showed a low interference response of the MPA-SHMP-capped CdTe quantum dots towards other metal ions. The highly efficient PL quenching ability in the presence of Hg 2+ or Cu 2+ ions due to the formed nonfluorescent metal complexes via robust Hg 2+ –O interaction with the carboxy oxygen elements of surface ligands of MPA, and on the basis of the competitive binding of the mercapto groups of the MPA between the CdTe quantum dots and the Cu 2+ ions, respectively, which allowed the analysis of Hg 2+ or Cu 2+ ions down to the picomolar levels. Under optimal conditions, the response of the MPA-SHMP-capped CdTe quantum dot PL intensity is linearly proportional to the Cu 2+ and Hg 2+ ion concentration ranging from 0.1 to 1000 and 0.3 to 1000 nM with a detection limit of 41.6 and 97.0 pM, respectively. The diagnostic capability and potential in practical applications of this method have been demonstrated by detecting Cu 2+ and Hg 2+ ions in environmental water samples.
研究领域:
分析化学
·
环境科学
·
纳米技术
✓ 已验证
DOI
LUMINESCENCE
·
2015
·Vol. 30
·期 7
·1112-1118
·
IF 1.518
Chenxia Hao,Shaopu Liu,Dan Li,Jidong Yang,Youqiu He
A sensitive and simple analytical strategy for the detection of sodium cromoglycate (SCG) has been established based on a readily detectable fluorescence quenching effect of SCG for glutathione-capped (GSH-capped) CdTe quantum dots (QDs). The fluorescence of GSH-capped CdTe QDs could be efficiently quenched by SCG through electron transfer from GSH-capped CdTe QDs to SCG. Under optimum conditions, the response was linearly proportional to the concentration of SCG between 0.6419 and 100 µg/mL, with a correlation coefficient ( R ) of 0.9964; the detection limit (3δ/K) was 0.1926 µg/mL. The optimum conditions and the influence of coexisting foreign substances on the reaction were also investigated. The very effective and simple method reported here has been successfully applied to the determination of SCG in synthetic and real samples. It is believed that the established approach could have good prospects for application in the fields of clinical diseases diagnosis and treatment. Copyright © 2015 John Wiley & Sons, Ltd.
研究领域:
分析化学
·
药物分析
·
生物医学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）