SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
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2022
·
IF 4.831
Peihua Li,Na Liang,Chao Liu,Lian Xia,Fengli Qu,Zhi-Ling Song,Rong-Mei Kong
In this work, a novel silver ion (Ag + )-regulated ratiometric fluorescence method for the effective and sensitive determination of alkaline phosphatase (ALP) was established based on carbon dots (CDs) and o -phenylenediamine (OPD). OPD can be oxidized by Ag + to generate fluorescent 2, 3-diaminophenazine (DAP). Thus, based on inner-filter effect (IFE) or/and fluorescence resonance energy transfer (FRET) between CDs and DAP, the CDs-Ag + -OPD system can generate dual-emission at 454 nm and 570 nm respectively when excited at 360 nm. The introduction of ascorbic acid (AA) can react with Ag + to produce dehydroascorbic acid (DHAA), which inhibits the generation of DAP, resulting in the fluorescence decrease at 570 nm and fluorescence recovery of CDs at 454 nm. Meanwhile, DHAA can react with OPD to generate quoxaline (QX), which emits strong blue fluorescence at 440 nm, further inhibiting the IFE or/and FRET between CDs and DAP. An obvious ratiometric fluorescence response was observed with the increase of the concentration of AA introduced. Due to the fact that AA can be generated by the enzyme catalysis reaction between ALP and 2-phospho- l -ascorbic acid (AAP), the CDs-Ag + -OPD ratiometric system was applied to the determination of ALP successfully. The ratiometric fluorescence value of F 454 / F 570 increases with increasing ALP concentration, with a linear range of 0.2 to 40 U/L and detection limit of 0.1 U/L. In addition, the CDs-Ag + -OPD ratiometric system was successfully applied to the detection of ALP in human serum samples.
研究领域:
分析化学
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生物医学
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PubMed
高影响因子
MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 3
·1-9
·
IF 5.479
Ma Yujun,Yu Ying,Lin Bixia,Zhang Li,Cao Yujuan,Guo Manli
Copper nanoclusters (CuNCs) were synthesized starting from glutathione and copper(II) nitrate. They show blue fluorescence peaking at 432 nm when excited at 334 nm. In the presence of o -phenylenediamine (OPD), the blue fluorescence is decreased, but a yellow fluorescence appears with a peak at 557 nm. UV-visible absorptiometry, fluorometry and fluorescence lifetime measurements were used to show that OPD is oxidized by the small fraction of copper(II) ions present in the CuNCs to form the oxidized form of o -phenylenediamine (oxOPD) which displays weak yellow fluorescence, while the blue fluorescence decreases. The ratio of fluorescences at 557 and 432 nm increases linearly in the 0.15 to 110 μg·L −1 OPD concentration range, and the detection limit is 93 ng·L −1 . Compared to the method based on the use of dissolved Cu(II), the employment of CuNCs reduces the detection limit by a factor of 40. The method was applied to the determination of OPD in spiked environmental water and industrial wastewater samples. Recoveries ranged from 96.8 to 100.3%.
Schematic presentation of a ratiometric fluorometric method for detection of o-phenylenediamine (OPD) based on copper nanoclusters (CuNCs). OPD is oxidized by Cu 2+ present in CuNCs to form the oxidized form of o -phenylenediamine (oxOPD). FRET occurred between oxOPD and CuNCs, and the F 557 /F 432 value is amplified.
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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PubMed
高影响因子
ANALYTICAL CHEMISTRY
·
2018
·
IF 6.042
Bin Bin Chen,Meng Li Liu,Lei Zhan,Chun Mei Li,Cheng Zhi Huang
Highly selective and sensitive detection of guanosine 3′-diphosphate-5′-diphosphate (ppGpp), namely, the stringent in plants or microorganisms responding to strict or extreme environmental conditions such as stress and starvation, which plays an important role in gene expression, rRNA and antibiotics production, regulations of virulence of bacteria, and growth of plants, faces a great challenge owing to its extreme similarity to normal nucleotides. By modifying the surface groups of a facile two-step hydrothermal route prepared carbon dots (CDs) with terbium ions (Tb3+) in this contribution, a novel fluorescent probe with excellent properties such as highly physical and chemical stability, narrow emission and excitation wavelength-independent emission was prepared. The Tb3+ ions on the surface of CDs cannot only preserve the intrinsic fluorescence (FL) of CDs but also keep its own coordination capacity with rare earth complex, and thus the clamp structure (four phosphate groups) of ppGpp can specific binding with Tb3+ ions on the surface of CDs to produce antenna effect. Therefore, a highly selective and sensitive fluorescent ratiometry of ppGpp was developed by terbium-modified carbon dots (CDs-Tb) with the limit of detection as low as 50 nM based on the synergistic effect of antenna effect of Tb3+ ions and specific recognition capacity of CDs. The applicability of this assay was demonstrated by CDs-Tb-based paper sensor for high distinguishing ppGpp from other nucleotides with similar structure.
研究领域:
生物化学
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分析化学
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分子生物学
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PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2018
·
IF 5.667
Yan Jun Ju,Na Li,Shi Gang Liu,Lei Han,Na Xiao,Hong Qun Luo,Nian Bing Li
The ratiometric fluorescence measurement has drawn great attention due to its selective and sensitive sensing property for numerous analytes. In this sensing system, a ratiometric fluorescence method is described for the determination of malachite green (MG) based on bovine serum albumin-stabilized Au nanoclusters (BSA-AuNCs) with dual emission. The as-prepared BSA-AuNCs exhibit two emission peaks around 430 and 610 nm under a single excitation, which may be from the intrinsic structure of BSA and AuNCs, respectively. As MG was added, the fluorescence at 610 nm was obviously quenched, and the fluorescence intensity at 430 nm decreased slowly, which might be mainly ascribed to fluorescence resonance energy transfer and dynamic quenching. The fluorescence intensity ratio of F 430 / F 610 shows good linearity for detecting MG in the 0.3–20 μM range with a low detection limit of 0.19 μM. In addition, the ratiometric sensing strategy is successfully applied to real water samples, which reveals its potential practicability for detecting MG in environmental water samples.
研究领域:
分析化学
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环境科学
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纳米技术
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DOI
高影响因子
MICROCHIMICA ACTA
·
2022
·Vol. 189
·期 4
·1-8
·
IF 6.408
An Xuanxuan,Tan Qin,Pan Shuang,Zhen Shujun,Hu Yongmei,Hu Xiaoli
A dual-emission ratiometric fluorescent sensing system based on boron-doped carbon quantum dots (B-CQDs) and gold nanoclusters (AuNCs) has been developed for the determination of xanthine. The blue fluorescence of B-CQDs at 445 nm is then reduced by the AuNCs through the inner filter effect (IFE) under a single excitation wavelength of 370 nm. By the catalysis of xanthine oxidase (XOD), xanthine is oxidized by oxygen dissolved in the solution to produce H 2 O 2 . The horseradish peroxidase (HRP) catalyzes H 2 O 2 to generate hydroxyl radicals, which can quench the fluorescence of AuNCs, leading to the recovery of the fluorescence of B-CQDs. Based on the relationship between the fluorescence intensity ratio ( F 445 / F 665 ) and the concentration of xanthine, the designed method exhibits a good linearity range of 1.2–500.0 μmol L −1 and a limit of detection of 0.37 μmol L −1 . The ratiometric fluorescent is applied to determine xanthine in human urine samples. Good recoveries of spiked samples in the range 99.2–105.0% are obtained by the proposed assay, with relative standard deviations (RSD) ranging from 0.9 to 2.6%. Graphical abstract
研究领域:
分析化学
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生物医学工程
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DOI
PubMed
高影响因子
ANALYTICA CHIMICA ACTA
·
2019
·
IF 5.256
Feng Zhang,Mengke Wang,Lili Zhang,Xingguang Su
Herein, we developed a novel and sensitive ratiometric fluorescence strategy for pH sensing and urea detection based on MoS 2 quantum dots (MQDs) and 2, 3-diaminophenazine (DAP). The DAP was pH-sensitive and can be used as pH indicator while MQDs was pH-insensitive and acted as a reference fluorescent signal. The fluorescence intensity of DAP at 568 nm exhibited increases gradually while the fluorescence intensity of MQDs at 420 nm kept unchanged as the pH changed from 3.0 to 9.0. So the ratio of the two fluorescence intensities at 568 nm and 420 nm can be used to monitor the change of pH. The pH-sensing system showed a linear and reversible respond to pH in the range of 3.8–6.0 with an interval of 0.2 pH unit. Furthermore, the enzymatic reaction of urea in the presence of urease can lead to the pH increase of the solution, which can be used to detect urea by using the above-mentioned pH-sensing system. There exhibited a good linear relationship between the ratiometric fluorescence intensity of I 568 /I 420 and urea concentrations ranging from 5 to 700 μM. And a low detection limit of 1.8 μM was obtained. The proposed strategy exhibited excellent selectivity and sensitivity. Additionally, the developed ratiometric fluorescence strategy was successfully applied to detect urea in water samples.
研究领域:
生物化学
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分析化学
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PubMed
高影响因子
Nanoscale
·
2019
·Vol. 12
·期 3
·2022-2027
·
IF 6.97
Chao Peng,Huanhuan Xing,Yuan Xue,Jin Wang,Jing Li,Erkang Wang
Two-dimensional (2D) Mn–Fe layered double hydroxide (LDH) nanosheets are firstly examined to mediate an O-phenylenediamine (OPD) based fluorescent switch in the presence of ascorbic acid (AA). On one hand, Mn–Fe LDH mimicked the functions of oxidase to catalyze the oxidation of OPD to OPDox, emitting fluorescence at 565 nm. On the other hand, Mn–Fe LDH acts as a superior catalyst for the reaction between AA and OPD to generate 3-(1,2-dihydroxyethyl)furo[3,4-b]quinoxalin-1(3H)-one (N-heterocyclic compound) with an emergence of the maximum emission at 425 nm (ca. 6 fold). The presence of AA not only induces the enhanced emission at 425 nm from the N-heterocyclic compound, but also leads to decreased fluorescence at 565 nm due to the decomposition of Mn–Fe LDH nanosheets. On the basis of the reversed fluorescence response at 425 and 565 nm, ratiometric fluorescence sensing methods (ΔF425 nm/ΔF565 nm) are developed for the determination of AA. With the assistance of alkaline phosphatase (ALP), the activity of ALP can be monitored using the ratiometric platform based on the hydrolyzing ascorbic acid 2-phosphate to yield AA with the detection limit of 0.16 mU mL−1. Different from the traditional ratiometric sensing platform, where two fluorescent probes are often introduced, the present ratiometric system derived from one signal precursor holds great potential in developing a facile platform and broadens the application of 2D nanomaterials in the field of biology.
研究领域:
生物化学
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纳米医学
·
分析化学
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DOI
PubMed
高影响因子
ANALYTICA CHIMICA ACTA
·
2019
·
IF 5.256
Zhihao Wu,Danyang Nan,Huan Yang,Shuang Pan,Hui Liu,Xiaoli Hu
A facile ratiometric fluorescence method for ascorbic acid (AA) detection was established by combining the fluorescence of MoS 2 quantum dots (QDs) with second-order scattering (SOS) of CoOOH. In MoS 2 QDs/CoOOH nanohybrid system, the fluorescence of MoS 2 QDs was quenched by CoOOH whereas the intensity of SOS was relatively close to the fluorescence due to the intrinsic high scattering ability of large size CoOOH nanoflakes . With the addition of AA, CoOOH nanoflakes were reduced to Co 2+ accompanied the size decline and the disappearance of characteristic absorption in UV–vis spectrum, resulting in the fluorescence recovery and SOS fading. Thus, the ratiometric detection of AA was obtained through the opposite changes of fluorescence and SOS. Under optimized conditions, the detection limit of AA was 0.21 μmol L −1 with a linear range from 0.80 to 32.0 μmol L −1 . Furthermore, the MoS 2 QDs/CoOOH nanohybrid system was applied to the detection of AA in human serum samples and vitamin C tablets with satisfactory results.
研究领域:
分析化学
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生物医学检测
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PubMed
高影响因子
MICROCHIMICA ACTA
·
2018
·Vol. 185
·期 11
·1-7
·
IF 5.705
Liang Si-Si,Deng Xu,Fan Yao-Yao,Li Jun,Wang Man,Zhang Zhi-Qi
CdTe quantum dots (QDs) were integrated with polyethyleneimine-coated carbon dots (PEI-CDs) to form a dually emitting probe for heparin. The red fluorescence of the CdTe QDs is quenched by the PEI-CDs due to electrostatic interactions. In the presence of heparin, the blue fluorescence of PEI-CDs remains unaffected, while its quenching effect on the fluorescence of CdTe QDs is strongly reduced. A ratiometric fluorometric assay was worked out. The ratio of the fluorescences at 595 and 436 nm serves as the analytical signal. Response is linear in the concentration range of 50–600 ng·mL −1 (0.1–1.2 U·mL −1 ) of heparin. The limit of detection is 20 ng·mL −1 (0.04 U·mL −1 ). This makes the method a valuable tool for heparin monitoring during postoperative and long-term care. This assay is relatively free from the interference by other analogues which commonly co-exist with heparin in samples, and it is more robust than single-wavelength based assays.
In the presence of heparin, the fluorescence of polyethyleneimine-coated carbon dots (PEI-CDs) at 436 nm remains unaffected, while its quenching effect on the fluorescence of CdTe at 595 nm is strongly reduced.
研究领域:
分析化学
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生物医学工程
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药物分析
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高影响因子
MICROCHIMICA ACTA
·
2018
·Vol. 185
·期 5
·1-9
·
IF 5.705
Huang Jianyong,Li Fenglan,Guo Rubin,Chen Yuyuan,Wang Zhenzhen,Zhao Chengfei,Zheng Yanjie,Weng Shaohuang,Lin Xinhua
Amino-modified carbon dots (C-dots) with positively charged surface were prepared. They display strong blue fluorescence and are shown to act as quenchers of the green fluorescence of FAM-labeled ssDNA such as the F-probe used in this work that was immobilized on the C-dots. On the addition of highly negatively charged heparin (Hep), it will interact with the C-dots and displace the F-probe from C-dots. Once the F-probe is displaced by Hep, its green fluorescence is restored. The intrinsic blue fluorescence of the C-dots remains stable after addition of Hep. Thus, a signal-on ratiometric fluorometric assay was developed for the ultra-sensitive detection of Hep. The underlying mechanisms of quenching and recovery are discussed. Under optimized conditions, the recovery of the ratiometric fluorescence of the system composed of C-dots and quenched F-probe is proportional to the Hep concentration in the range of 0.01–2.0 μg·mL −1 (= 0.00125–0.25 U·mL −1 ). The method was successfully applied to the determination of Hep in spiked serum samples.
Schematic of a signal-on ratiometric fluorometric method for the ultra-sensitive detection of heparin on the basis of the displacement and fluorescence enhancement of adsorbed FAM-labeled ssDNA from amino-modified carbon dots (C-dots) by heparin.
研究领域:
生物化学
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分析化学
·
医学检验
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PubMed
高影响因子
BIOSENSORS & BIOELECTRONICS
·
2015
·
IF 6.409
Meiding Yang,Jian Chen,Huipeng Zhou,Wenying Li,Yan Wang,Juanmin Li,Cuiyun Zhang,Chuibei Zhou,Cong Yu
A benzoperylene probe excimer emission in an aqueous buffer solution is observed for the first time, and a novel ratiometric fluorescence method based on the probe excimer emission for the sensitive detection of heparin and heparinase is demonstrated. A negatively charged benzoperylene derivative, 6-(benzo[ghi]perylene-1,2-dicarboxylic imide-yl)hexanoic acid (BPDI), was employed. A polycation , poly(diallyldimethylammonium) chloride (poly-DDA), could induce aggregation of BPDI through noncovalent interactions. A decrease of BPDI monomer emission and a simultaneous increase of BPDI excimer emission were observed. Upon the addition of heparin, the strong binding between heparin and poly-DDA caused release of BPDI monomer molecules, and an excimer–monomer emission signal transition was detected. However, after the enzymatic hydrolysis of heparin by heparinase, heparin was hydrolyzed into small fragments, which weakened the competitive binding of heparin to poly-DDA. Poly-DDA induced aggregation of BPDI, and a monomer–excimer emission signal transition was detected. Our assay is simple, rapid, inexpensive, sensitive and selective, which could facilitate the heparin and heparinase related biochemical and biomedical research.
研究领域:
分析化学
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生物化学
·
生物医学工程
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DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2025
·
IF 9.8
Xiaoqi Jiang,Jingcheng Huang,Mengting Li,Linjin Li,Yinuo Chen,Jiangfei Chen,Junlun Zhu,Xuedong Wang,He Mei
Detecting tetracyclines' (TC) residues is of great significance for evaluating the food and environmental safety. Herein, we pioneered a reversible-responsive ratiometric fluorometry by integrating the red fluorescence of Eu 3+ /GMP lanthanide coordination polymers (Eu 3+ /GMP LCPs) with the blue fluorescence of an anthracene-based imidazolium ionic liquid (ABIIL). In the presence of TC, the fluorescence of ABIIL was quenched by TC via the inner-filter effect and photoinduced electron-transfer process, but that of Eu 3+ /GMP LCPs was enhanced owing to the antenna effect between Eu 3+ and TC. Based on the reversible variations of the fluorescence signals, a fluorescent assay based on ABIIL-Eu 3+ /GMP LCPs was engineered to detect TC with satisfactory sensitivity and selectivity. A good linearity for TC was acquired from 0 to 50 μM with the detection limit of 3.0 nM and the significant color changes. Therefore, the assay was a promising approach for the visual detection of TC in complex media
研究领域:
分析化学
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食品安全
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环境监测
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荧光传感
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药物残留检测
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材料化学
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分子识别
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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）