Materials Express
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2020
·Vol. 10
·期 7
·1135-1140
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IF 1.65
Shen Yongling,Wu Hongyi,Wu Weihui,Zhou Lei,Dai Zhifei,Dong Shuangping
A new carbon source (mint) is proposed to prepare carbon dots with excellent photostability and strong photobleaching properties by one-step hydrothermal method. The average particle diameter for carbon dots is 5.0 nm, emitting blue luminescence, and the quantum yield is 4.5%. Fluorescence
can be obviously quenched in Fe3+ solution. Further, A method based on fluorescence quenching of carbon dots for detecting Fe3+ is established, which has a linear range of 0.5∼100 μM with a detection limit of 0.104 μM. This may provide an easy
and sensitive method for iron detection.
研究领域:
材料科学
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分析化学
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高影响因子
OPTICS COMMUNICATIONS
·
2020
·
IF 2.125
Lu Zhang,Zhenglan Bian,Anduo Hu,Jinglin Li,Lei Liu,Fenghong Chu
This paper presents an iodine ions fluorescence quenching sensor based on hydrogel fiber doped with fluorescein. The hydrogel fiber was made by photo-crosslinking with core-cladding structure made from PEGDA precursor solutions with different concentration. Compared with calcium alginate cladding material, this structure is less susceptible to damage and the thickness of the cladding is controllable, which significantly reduces the loss of the hydrogel fiber. Experimental results show that the loss of the cladding-free hydrogel is 1.669 dB/cm ± 0.4 dB/cm, and the loss of the core-cladding hydrogel fiber is 0.597 dB/cm ± 0.2 dB/cm. By analyzing the properties of different hydrogel precursor solutions before and after photo-crosslinking, a functional hydrogel fiber doped with fluorescein for measuring iodine ions with numerical aperture of 0.3932 and mode number about 17 was fabricated. The hydrogel fiber shows high coupling efficiency with PMMA plastic optical fiber . The sensor of iodine ions exhibited a linear range of 0 ∼ 36 mM and the detection limit was calculated to be 26nM. The system also shows good stability and repeatability. Hydrogel fibers shows good biocompatibility and flexibility, which will have broad application prospects in biological area in the future.
研究领域:
生物医学工程
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分析化学
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高影响因子
JOURNAL OF MATERIALS CHEMISTRY
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2011
·Vol. 22
·期 2
·462-469
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IF 5.101
Ye Cui,Xiaoqun Gong,Shengjiang Zhu,Yunhong Li,Wenya Su,Qiuhua Yang,Jin Chang
In this paper, a biocompatible poly(γ-glutamic acid) (PGA)-based polymer with numerous thiol groups grafted onto the backbone was self-synthesized. It has been successfully used to prepare water-soluble quantum dots (QDs) with high luminescence and high stability. FTIR spectroscopy, transmission electron microscopy, dynamic light scattering, spectrofluoro-photometry, fluorescence microscopy and flow cytometer were used to characterize QDs@poly(γ-glutamic acid)-grafted cysteamine (PGA-g-MEA). The results indicated that QDs@PGA-g-MEA with an identical small size were highly luminescent with a well maintained, even increased, photoluminescence (PL) intensity when compared with the tributylphosphine oxide (TOPO) coated QDs. Meanwhile, they were highly stable in aqueous solution under a wide range of pH from 2 to 12, as well as under different temperatures. The QDs@PGA-g-MEA were then applied as fluorescent probes to detect human IgGs and the results demonstrated that QDs@PGA-g-MEA had great potential for application in immunofluorescence.
研究领域:
生物化学
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纳米医学
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分析化学
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DOI
高影响因子
Journal of Materials Chemistry B
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2019
·Vol. 7
·期 15
·2549-2556
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IF 5.047
Yaping Zhong,Tao Yi
We report a one-step hydrothermal method for the preparation of fluorescent molybdenum disulfide quantum dots (MoS2 QDs) and demonstrate the feasibility of fluorescent “turn-off–on” sensing of adenosine triphosphate (ATP) by using the MoS2 QDs. MoS2 QDs having strong blue-green fluorescence at 506 nm and good water-solubility were successfully synthesized by using ammonium tetrathiomolybdate as a single precursor. The fluorescence of MoS2 QDs was first quenched by Fe3+ through the formation of a MoS2 QDs/Fe3+ complex. ATP with the ability to coordinate with Fe3+ caused the dissociation of MoS2 QDs/Fe3+, resulting in the final release of MoS2 QDs and the recovery of fluorescence through a one-step competitive chelating process that took only 10 min to reach equilibrium at room temperature (RT). Facile and rapid sensing of Fe3+ and ATP could thus be achieved through the fluorescent “turn-off–on” strategy. Good linear relationships were obtained over the concentration ranges of 0–200 μM for Fe3+ and 0–140 μM for ATP with a lowest detectable concentration of 5 μM for ATP. Satisfactory results were obtained when the method was applied to a standard addition recovery trial of ATP in human serum samples. No complex surface modification during the preparation or detection process was needed based on the fluorescent “turn-off–on” method of the MoS2 QDs, which suggests its great potential in fluorescent sensing.
研究领域:
分析化学
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生物传感
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材料科学
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DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2022
·
IF 9.221
Lixia Guo,Xueyun Zhang,Danning Wen,Lei Ding,Yan Niu,Lihong Li,Wen Liu,Haipeng Diao,Liheng Feng
Accurate measurement of pH is of great significance in the research of biology and medicine sciences. Cell is the basic unit of living organism and the proper pH of cytoplasm and organelles such as lysosome is the precondition to maintain its function. Alteration of pH may impair the normal process of cells and lead to occurrence of diseases. Sensitively sensing the pH of cytoplasm and organelles is of great value for biomedical research. Due to the complexity of biological microenvironment , it is still challenging to simultaneously detect the pH changes of cytoplasm and lysosome. Here, we reported a ratiometric pH probe with NIR fluorescence termed as PCHC, which realized sensitive cytoplasmic and lysosome pH detection. The probe was prepared by connecting coumarin with dicyanmethylene-4H-pyran via amidation reaction, and displays large Stoke-shift, good biosafety and pH selectivity. After entering the cell, the probe shows blue in cytoplasm and NIR fluorescence in lysosome due to respective pH. The ratio of blue and NIR fluorescence signal can be served as indicator to monitor pH change of cytoplasm and lysosome simultaneously, which has potential application for investigation of pH alteration related diseases.
研究领域:
生物医学
·
细胞生物学
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DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2015
·
IF 4.097
Fan Zhang,Jian Zhu,Jian-Jun Li,Jun-Wu Zhao
Au nanoparticles-based fluorescence quenching has been widely used for many analytes due to its high sensitivity and rapid response. However, the effects of different coating agents of Au nanorods on the assays performance remain unclear. For the first time, we demonstrated that the coating agents play a significant role in Au nanorods-based fluorescence quenching and recovery on Rhodamine 6G (R6G). Polystyrenesulfonate (PSS)-coated Au nanorods could almost totally quench the fluorescence intensity of R6G, whereas cetyltrimethyl ammonium bromide (CTAB)-coated Au nanorods and bare Au nanorods only have little effect on the fluorescence of R6G. The addition of cysteine to PSS-coated Au nanorods-R6G makes the fluorescence recover gradually, even greater than the original fluorescence intensity of R6G. Thus the PSS-coated Au nanorods-R6G could be served as a fluorescent probe to detect cysteine. The fluorescence intensity change of PSS-coated Au nanorods-R6G probe is linear with logarithm of Cys concentration over the range from 0.01 to 2.5 μg/mL. The results provide theoretical guidance for further improving Au nanorods-based fluorescence quenching and detection of protein molecules by the fluorescence off-on mechanism.
研究领域:
分析化学
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生物医学工程
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纳米技术
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DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2015
·
IF 4.097
Fanyong Yan,Dechao Shi,Tancheng Zheng,Kaiyi Yun,Xuguang Zhou,Li Chen
An “Off–On” approach for highly sensitive and selective detection of mercury ions (Hg 2+ ) and l -cysteine ( l -Cys) was demonstrated with the use of water-soluble carbon dots (CDs) as novel fluorescent probe. In this present sensing system, Hg 2+ cations can efficiently coordinate onto the surface of CDs by means of electrostatic interactions and remarkably quench the fluorescence signal of CDs as a result of the fluorescence charge transfer (turn-off). In addition, the resulting CDs-Hg 2+ system was observed to be sensitive to l -Cys due to the ability of l -Cys to coordinate with Hg 2+ and the formation of strong Hg 2+ -SR bond. When l -Cys was added, Hg 2+ combined with l -Cys rather than with CDs resulting in the remove of Hg 2+ from the surface of CDs and shielding of fluorescence quenching, and thus, a significant fluorescence restore of CDs was observed (turn-on). Under the optimized conditions, good linearity for detecting Hg 2+ was attained over the concentration range from 2 to 22 μM with a detection limit of 0.017 μM, while the concentrations of l -Cys ranging from 2 to 20 μM exhibited a linear relationship with the relative fluorescence intensity with a correlation coefficient of R 2 = 0.99329. Moreover, this CDs-based sensor was successfully applied for visual identification and quantitation of Hg 2+ and l -Cys in real water sample and fluorescence imaging of NIH-3T3 cells with satisfying resolution.
研究领域:
分析化学
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环境科学
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生物医学
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DOI
高影响因子
Analytical Methods
·
2014
·Vol. 6
·期 22
·9073-9077
·
IF 1.938
Yu Zhang,Liqian Wu,Yurong Tang,Yingying Su,Yi Lv
A new fluorescent probe for detecting lead ions (Pb2+) is reported in this work. Positively charged UCPs capped with ethylene imine polymer (PEI) and negatively charged AuNPs capped with 11-mercaptoundecanoic acid (MUA) were used as fluorescent donors and acceptors, respectively. The fluorescence quenching process was initiated by the electrostatic interaction between PEI–UCPs and MUA–AuNPs. Upon the addition of Pb2+, functionalized AuNPs were aggregated by an ion-templated chelation process, causing the departure of AuNPs from UCPs. As a result, the fluorescence of the donor was restored and the recovery was found to be proportional within the range of 0.5–10 μM to the concentration of Pb2+. The detection limit was found to be 20 nM. This method was easy to operate with satisfactory selectivity and remarkable sensitivity which would be meaningful in Pb2+-related detection.
研究领域:
分析化学
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环境科学
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DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2013
·
IF 2.144
Huilin Tao,Xiufen Liao,Mingze Xu,Shuhuai Li,Fuxin Zhong,Zhongsheng Yi
The fluorescence resonance energy transfer between fluorescent brightener (FB, donor) and CdTe quantum dots (CdTe QDs, acceptor) was studied and a new method for detecting Hg 2+ ions in water samples was accordingly developed in this paper. It was found that the effective energy transfer occurred from FB to CdTe QDs in Tris–HCl buffer solution at pH=8.2, in which the QDs' fluorescence intensity increased greatly. Then the fluorescence quenching occurred as Hg 2+ interacted with CdTe. Under the optimized conditions, there was a linear relationship between the fluorescence quenching intensity and the concentration of Hg 2+ . Hg 2+ could be determined in the concentration range of 8.0×10 −9 –8.0×10 −7 g L −1 with a detection limit of 6.6×10 −10 g L −1 ( S / N =3). The method was applied to the determination of Hg 2+ in water samples via the standard addition method, and the recovery rate obtained was 97.3–105.5%.
研究领域:
分析化学
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环境科学
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DOI
高影响因子
Toxics
·
2022
·Vol. 10
·期 7
·367
·
IF 4.472
Dengpeng Wang,Feng Gao,Xianran Wang,Xiaomei Ning,Kaituo Wang,Xinpeng Wang,Yuezhou Wei,Toyohisa Fujita
The detection of heavy metals in aqueous solutions has always attracted much attention from all over the world. A fluorescent probe of CdSe/CdS core-shell quantum dots (QDs) was designed to detect trace Cd2+in aqueous solutions using the OFF–ON mode rapidly and efficiently, likely based on adsorption and desorption reactions between ethylenediaminetetraacetic acid disodium salt (EDTA) and CdSe/CdS QDs. In the OFF mode, the optical shielding function of EDTA results in fluorescence quenching owing to the strong adsorption ability of EDTA with Cd2+on the sites of CdSe/CdS QDs surface. In the ON mode, the introduction of Cd2+promotes the desorption of EDTA from the EDTA-CdSe/CdS QDs and restores the fluorescence intensity. There were two linear response ranges which were 0.1–20 µmol/L and 20–90 µmol/L for the EDTA-CdSe/CdS system to detect Cd2+. The detection limit was 6 nmol/L, and the standard deviation was below 4% for the detection of Cd2+concentration in tap water.Keywords:QDs;fluorescence quenching;fluorescence restore;Cd2+detection;adsorption;desorption
研究领域:
分析化学
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环境科学
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Xirui Chen,Yujie Tu,Song Cheng,Xujing Guo,Tianying Lu,Yuqian Guo,Xiaolin Huang,Yonghua Xiong,Ben Zhong Tang
Existing single-signal-response fluorescent materials for biogenic amine detection have unsatisfactory detection performance. Herein, we developed a simple pH-sensitive aggregation-induced emission-active fluorogen (AIEgen) and demonstrated its potential for ratiometric monitoring of biogenic amines. This AIEgen, namely 4-(dimethylamino)styryl)quinoxalin-2(1 H )-one (ASQ), shows a typical donor (D)-acceptor (A) structure with nonmonotonic color and fluorescence responses to pH stimulation by its protonation/deprotonation on the D/A moieties. Subsequently, the H + ASQ-labeled paper chips were successfully prepared by physically depositing ASQ on qualitative filter paper, followed by the acidification by hydrochloric acid. Upon the exposure to ammonia vapour, the obtained H + ASQ-labeled paper chips exhibited obvious color and ratiometric fluorescence responses owing to the deprotonation of H + ASQ indicators, indicating that the proposed paper chips can be used for the detection of biological amines by bimodal colorimetry and ratiometric fluorescence. Under the optimal conditions, H + ASQ-labeled paper chip achieved the real-time, non-destructive, and visual monitoring of meat and seafood freshness by simultaneously quantify the biogenic amine index with high performance liquid chromatography (HPLC). The results of this work suggest that ratiometric AIEgen can serve as a promising alternative strategy to ensure accurate monitoring of biogenic amines and food freshness.
研究领域:
分析化学
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食品安全
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生物传感
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DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2021
·
IF 9.381
Shuangyu Xiong,Wei Sun,Rong Chen,Zhiqiang Yuan,Xinjian Cheng
Fluorescent hydrogel with proper hydrophilicity and thermal stability , excellent sensitivity and high selectivity has important practical and scientific significance, especially in heavy metal ion detection. In this work, by adjusting the content of [2, 6-Bis-[4-formylthiophene]]-1,3,5,7-tetramethyl-8-phenyl-4, 4-difluoroborazaindoloene (B3), as a cross-linking agent, a series of chitosan- fluoroboron dipyrrole-chitosan-based fluorescent hydrogels (CBC) with large stokes shift were designed and prepared. The hydrogels can be used as fluorescent probes for identifying Cu 2+ in aqueous solution. The linear quenching range of Cu 2+ is 0–50 μM, and the detection limit and quenching constant are 4.75 μM and 3.52 × 10 4 M −1 , respectively. Under the interaction of Cu 2+ , the imine bond C N was converted to C- N bond, which causes the phenomenon of fluorescence quenching . In addition, relatively high crosslink density improves hydrophilicity and thermal stability of initial chitosan, and made the swelling ability better.
研究领域:
分析化学
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材料科学
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DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）