INTERNATIONAL JOURNAL OF ENVIRONMENTAL ANALYTICAL CHEMISTRY
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2023
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IF 2.6
Junfang Chang,Jie Mao,Yifei Lu,Yalei Liu,Sui Wang
Water-soluble purple fluorescent carbon nanodots (P-CDs) were synthesised using 2-phenylphenol, and red fluorescent carbon dots (R-CDs) were prepared from o-phenylenediamine and phosphoric acid. Based on the fluorescence quenching effect of Ag+ on carbon quantum dots, and additionally introducing a red light-emitting quantum dot with excellent performance and high quantum yield, a dual emission ratiometric fluorescent nanosensor (P-CDs/R-CDs) was established. The semi-quantitative detection of silver ions can be realised. Under the excitation light of 254 nm and 365 nm, the fluorescence spectrum shows double emission fluorescence peaks at 343 nm and 626 nm, which originate from the fluorescence emission of the synthesised C-dots and the additionally introduced C-dots, respectively. The relationship between the ratio of the intensity of the two emission peaks F343/F626 and the concentration of silver ions realises the analysis and detection of silver ions. The linear detection range of this method was 0.096–10 μM, and the detection limit (LOD, S/N = 3) was 32 nM. In addition, the method can also perform naked-eye visual detection according to the fluorescence colour change of the probe under ultraviolet light, and realise the rapid monitoring of Ag+ on site. The P-CDs/R-CDs ratiometric fluorescence sensor provides a new method for the detection of Ag+ and promotes the development of heavy metal ion sensing.
研究领域:
分析化学
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环境科学
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纳米材料科学
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DOI
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
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2022
·Vol. 414
·期 13
·3999-4009
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IF 4.478
Zhang Liule,Gao Xia,Chen Xiying,Zhao Minyang,Wu Haotian,Liu Yaqing
In view of the high toxicity and widespread availability, it is of great importance to develop accurate, sensitive, and convenient assays for fluoride ion (F − ) detection. Herein, a ratiometric fluorescent system is established for point-of-care testing (POCT) of F − with a smartphone as analyzer. The sensing system of calcein-QDs-Eu 3+ contains two fluorescent probes of calcein (green emission) and ZnCdSe/ZnS QDs (red emission). The sensing system only presents red emission in that the calcein emission is quenched due to the combination between calcein and Eu 3+ . When F − is introduced, the fluorescence of calcein is recovered due to the stronger interaction between F − and Eu 3+ , which changes the emission from red to green. The ratiometric strategy offers an obvious fluorescence color change of the system, which eliminates interference and improves the detection accuracy. Specifically, the sensing system has excellent selectivity in that Eu 3+ is more inclined to bind with F − rather than other anions. The developed assay was further used to prepare a test paper and hydrogel for POCT. To further improve the detection sensitivity and realize quantitative analysis, a smartphone installed with a color scan app is integrated as signal reader and analyzer, which is used for POCT of F − in real samples, showing great application potential in environmental protection and food safety evaluation. Graphical abstract
研究领域:
分析化学
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环境科学
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食品安全
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DOI
高影响因子
APPLIED SURFACE SCIENCE
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2022
·
IF 7.392
Yong Han,Hui Wang,Ying Yu,Weixia Yang,Fei Shang,Zhonghong Li
Nano-hybrid carbon dots (CDs) with multiple emissions always endure fluorescence quenching induced by the interactions of chemical groups between hybrid CDs and nanomaterial, the samples with abundant interferences by an ordinary pretreatment. Lanthanide ion (DPA-Tb) was employed to hybridize PAN-CDs for the fabrication of ratiometric fluorescent sensor (PAN-CDs&DPA-Tb) to detect Carbendazim (MBC) in complicated food samples with facile pretreatment. The impacts of hybridization on the fluorescence of PAN-CDs were evaluated through dynamic characterizations, which manifested that DPA-Tb and the sensing matrix had no significant influence on the ratiomeric fluorescence of PAN-CDs&DPA-Tb sensor. The sensor (F 363 /F 544 ) linearly responded to concentrations of MBC in 0–0.091 mmol/L with a limit of detection (LOD) of 3.0 × 10 -3 μmol/L and satisfactory applications with recoveries of 92.22–106.08% and RSDs of 0.14–1.69%. The strategy provides a novel sight to investigate the fabrication of CDs-based ratiometric fluorescent sensors.
研究领域:
分析化学
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食品安全
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纳米技术
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DOI
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
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2017
·Vol. 409
·期 28
·6655-6662
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IF 3.431
Li Hongmei,Wang Xuefeng,Cai Zheng,Lu Ling,Tao Jia,Sun Bin,Yang Yuanyuan,Xu Quan,Yu Zhiqiang,Zhao Peng
Copper ions play a significant role in human bodies, as they are beneficial for many metabolism processes, but excessive Cu 2+ may cause various symptoms. Therefore, the development of strategies capable of both sensitive detection and visualization of Cu 2+ is greatly important for human health. In this work, a novel ratiometric fluorescence sensor for rapid and visual detection of Cu 2+ was designed based on green emission carbon dots (CDs) and red emission CdTe/CdS quantum dots (QDs). We have calculated the chromaticity coordinates of individual CDs and CdTe/CdS QDs, and the chromaticity coordinate of their mixture would change along the line between the two points of CDs and CdTe/CdS QDs in the chromaticity coordinate system. The red fluorescence of QDs can be influenced by Cu 2+ , and the fluorescence color of CDs-QDs changes from yellow to green as the chromaticity coordinates change with the addition of Cu 2+ . This traffic-light-type color change was more sensitive to the naked eye compared to conventional single emission-based sensors. This paper not only realized ratiometric fluorescence and visual detection of Cu 2+ through a convenient method but also provided a promising strategy of designing an assay kit for trace Cu 2+ .
Ratiometric fluorescent sensing of copper ion based on chromaticity change strategy
研究领域:
分析化学
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生物医学
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DOI
PubMed
高影响因子
TALANTA
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2019
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IF 4.916
Wei Wei,Jiang He,Yingying Wang,Mengjuan Kong
A silicon nanodots (SiNDs)-based ratiometric fluorescent sensor was designed to establish highly sensitive and selective method for detection of tetracyclines (TCs). The sensor comprises the blue fluorescence SiNDs were prepared by hydrothermal method synthesis from (3-aminopropyl)triethoxysilane and low-cost diethylenetriaminepentaacetic acid as the precursor, which serve as co-ligands for covalently bond with europium ions (Eu 3+ ), and also the internal reference signal. In the presence of TCs, the luminescence intensity of Eu 3+ was significantly increased, while the luminescence intensity of SiNDs was reduced. The fluorescence intensity ratio of I 616 /I 450 of the sensor exhibits a sensitive linear range from 0.2 to 20 μM with a detection limit of 3 nM for the detection of TCs. This method was successfully applied to determine the levels of TCs in nature river samples and milk samples with good recoveries ranges from 92.2% to 107.4% and relative standard deviations (RSD, n = 3) was below 5%, providing a promising application future in real samples.
研究领域:
分析化学
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环境科学
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食品科学
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DOI
PubMed
高影响因子
RSC Advances
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2017
·Vol. 7
·期 85
·53977-53983
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IF 3.108
Qin Sun,Liang Yang,Lei Su,Weikang Liu,Yifan Wang,Shaoming Yu,Changlong Jiang,Zhongping Zhang
Precise control of the size, shape, and composition of nanocrystals will be required to fully explore and utilize unique properties of nanomaterials with a broad range. In this manuscript we have designed colloidal QD chains, using carboxyl-modified red fluorescent cadmium telluride (CdTe), which were self-assembled by the mediation of trithiocyanuric acid (TTCA). Furthermore, a ratiometric fluorescent sensor with dual-emissions was constructed by mixing the QD chains with blue fluorescent carbon dots (CDs) for the visual ultrasensitive detection of As(III) in environmental water. In the process of As3+ detection, it could react with the third sulfydryl, which resulted in the agglomeration of QD chains and quenching of the red emission of the QDs, while the blue fluorescent CDs were insensitive to the analyte. So the variation of fluorescence intensity ratios produces an obvious change of the fluorescence color from fushia to blue, which can be conveniently observed by the naked eye under a UV lamp without any complicated instrumentation. The LOD of this ratiometric fluorescent probe could reach as low as 1 ppb, which is much lower than the maximum level of 10 ppb As3+ in drinking water stipulated by WHO. Following the sensing mechanism, a paper-based sensor has been prepared by printing the ratiometric probe on filter paper, which provides a convenient and simple approach for the visual detection of As3+. Therefore, the very simple and effective strategy reported here could be extended to the visual detection of a wide range of analytes in the environment by the construction of highly efficient ratiometric nanoprobes.
研究领域:
纳米材料科学
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环境分析化学
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生物传感
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DOI
高影响因子
LUMINESCENCE
·
2023
·Vol. 38
·期 2
·152-158
·
IF 2.9
Jiayi Liu,Yibing Liu,Wei Wang,Siqi Zhang,Li Tang,Pinyi Ma,Daqian Song,Qiang Fei
Over the past few years, ratiometric fluorescent nanoprobes have garnered substantial interest because of their self-calibration characteristics. This research developed a ratiometric fluorescent sensor to detect phosphate. Through encapsulating luminescent materials, gold nanoclusters (AuNCs) and carbon dots (CDs) into a zeolitic imidazolate framework-8 (ZIF-8), the fluorescence signal of AuNCs was enhanced, while that of CDs was suppressed. After phosphate was added, it could decompose ZIF-8, and AuNCs and CDs were released, which weakened the fluorescence signal of the AuNCs while restoring that of the CDs. Thereby, this makes CDs/AuNCs@ZIF-8 a potential fluorescent sensor for phosphate determination. The ratiometric sensor had facile synthesis, good selectivity, and a low detection limit. Therefore, this sensor was an effective tool for the detection of phosphate.
研究领域:
分析化学
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材料科学
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环境科学
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产品关联
DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
·
2023
·
IF 4.8
Sizhe Zhang,Qi Pu,Xinyi Deng,Lu Zhang,Nengsheng Ye,Yuhong Xiang
Choline (ChO) is a biomarker of many diseases. Its accurate and sensitive detection is of great significance for the diseases diagnosis. Gold nanoclusters with bovine serum albumin as template (BSA-AuNCs) were synthesized by microwave-assisted method. A ratiometric fluorescence sensor was constructed based on BSA-AuNCs and 2,3-diaminophenazine, which was the oxidation product of o-phenylenediamine. Combined with cascade enzymatic reaction, it was used for the detection of choline. In the detection system, choline oxidase improved the selectivity of detection, and the peroxidase-like activity of molybdenum disulfide nanosheets shortened the detection time. The linear ranges of choline detection by ratiometric fluorescence sensor were 0.5–20 μM and 20–100 μM. The detection limit was 0.27 μM. The ratiometric fluorescence sensor was easy to operate and had good selectivity. Compared with single signal sensor, it can effectively reduce the error interference such as environmental change, and the detection result was more accurate.
研究领域:
分析化学
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生物医学
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产品关联
DOI
高影响因子
MICROCHIMICA ACTA
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2022
·Vol. 189
·期 2
·1-10
·
IF 6.408
Wu Xia,Meng Xufeng,Hou Baoxiu,Sun Zhong,Zhang Yunyi,Li Ming
A smartphone-assisted fluorescence color sensing system for rapid, convenient, and on-site detection of copper ions was developed. The ratiometric fluorescence sensor was fabricated by using silica-coated blue-light-emitting carbon dots and surface-grafted red-light-emitting cadmium-telluride quantum dots. After exposure to Cu 2+ in 20 s, the red fluorescence was quenched obviously, while the blue fluorescence remained unchanged, and the sensor color changes continuously from red to blue under the ultraviolet lamp. The concentration (50–1200 nM) of copper ions could be measured by the fluorescence spectrum (excitation at 360 nm, dual-emission at 441 and 640 nm) with a detection limit of 7.7 nM. The fluorescence colors were converted to digital RGB values to calculate the concentration of copper ions by a smartphone with a detection limit of 9.6 nM. The method was applied to detecting copper ions spiked in real samples with recovery from 97.9 to 108.0% and RSD from 3.8 to 8.9%. Thus, this convenient and practical fluorescence color sensing system presents a new strategy for rapid, sensitive, and on-site determination of copper ions in environmental or biological samples. Graphical abstract
研究领域:
分析化学
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环境科学
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生物传感
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DOI
PubMed
高影响因子
DYES AND PIGMENTS
·
2024
·
IF 4.1
Bo Peng,Mingyu Li,Huijing Chen,Ping Zhang,Xue Hu
Quantification of fluorescent assays with smartphones has great promise in environmental monitoring for providing on-site visual detection. However, the analytical performance of these fluorescence sensors based on single-color channels is usually unable to satisfy the detection accuracy. Here, we propose a smartphone-assisted ratiometric fluorescence-sensing platform based on dual-emission copper nanoclusters ( Cu NCs ) for precisely determining Pb 2+ concentrations. The Cu NCs were prepared by using dithiothreitol ( DTT ) as reducing and stabilizing agents, which possess two intrinsic emission centers located at 450 nm and 620 nm, respectively. In presence of Pb 2+ , the red fluorescence at 620 nm of the Cu NCs were quenched via photoinduced electron transfer process, meanwhile the blue fluorescence at 450 nm could be maintained unchanged. Thus, a ratiometric fluorescence sensing of Pb 2+ was facilely fabricated based on the Cu NCs without introducing other fluorescent materials as the reference, allowing sensitive and selective determination of Pb 2+ with a limit of detection (LOD) of 2 nM. Moreover, extracting the fluorescence color changes of this sensor under the supporting of a smartphone app, a portable sensing platform was constructed for visual detecting Pb 2+ with LOD of 0.05 μM, showing great potential for on-site monitoring of Pb 2+ .
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
Food Chemistry-X
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2024
·
IF 6.5
Doudou Lei,Lingling Li,Pengyue Song,QingBin Xu,Lihua Huang,Xiao Ma,Lidong Zhou,Weijun Kong
Glyphosate (Gly) is a widely-used herbicide in food production, while, the residue of which due to the long-term and excessive overspray poses serious threats to public health. The development of reliable methods for its sensitive detection is of great urgency. In this study, a novel ratiometric fluorescent nanosensor by encapsulating N-doped carbon dots (N-CDs) and gold nanoclusters (AuNCs) in zeolitic imidazole framework-8 (ZIF-8) as the dual-emissive fluorescence probes at 410 and 650 nm, respectively, was constructed for Gly detection. Due to the adsorption property of ZIF-8, the N-CDs/AuNCs@ZIF-8 nanoprobes accumulated Cu 2+ to quench the red fluorescence of AuNCs, and the blue fluorescence of N-CDs was stable. While thiocholine, a product of acetylthiocholine, hydrolyzed by acetylcholinesterase could coordinate with Cu 2+ , resulting in significant fluorescence recovery of AuNCs. This phenomenon was utilized for the quantitation of Gly, due to its inhibitory effect on acetylcholinesterase activity. By calculating the fluorescence intensity ratio ( I 650 /I 410 ), Gly in real sample could be accurately determined in a concentration range of 2–100 ng/mL with a limit of detection of 1.92 ng/mL because of the anti-interference and the self-correction ability of the two fluorescence signals. The N-CDs/AuNCs@ZIF-8 nanoprobes-assisted ratiometric fluorescent nanosensor exhibited unique merits of rapid construction, simple operation, high specificity, and good accuracy for Gly in edible and medicinal malt samples with recoveries of 93.7–108.2 %. This study presents a multiple tool for the versatile sensing of trace pesticides in more food matrices, which can be extended to a full range of environmental and food safety applications.
研究领域:
分析化学
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食品安全
·
环境科学
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产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
Yilan Zhao,Xue Jiang,Ke Huang,Xiaoli Xiong,Qing Yang
A switchable ratiometric fluorescent smartphone-assisted sensing platform based on nitrogen-doped carbon dots (N-CDs) and Rhodamine B was fabricated for the determination of the ascorbic acid (AA) content in fruits by quenching the fluorescence of N-CDs with Hg 2+ (turn-off) and recovering with AA (turn-on). The blue-emission N-CDs was synthesized by liquid dielectric barrier discharge microplasma with an average size of 3.65 nm and an absolute quantum yield of 18 % (excited at 345 nm). In addition, the fluorescence color was converted to RGB values, enabling visual and quantitative determination of AA. Under optimal parameters, the linear ranges for detecting AA were found to be 3–170 μM and 5–170 μM for fluorescence spectrometer and smartphone sensing platform. The detection limits were 0.98 μM and 2.90 μM, respectively. Furthermore, the satisfactory recoveries in fruits were obtained by RF probe and smartphone platform. This smartphone-assisted platform will facilitate sensitive and visual determination for AA.
研究领域:
分析化学
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食品科学
·
生物医学工程
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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）