ANALYTICAL AND BIOANALYTICAL CHEMISTRY
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2019
·Vol. 411
·期 14
·3081-3089
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IF 3.286
Zhang Ying,Ren Wang,Fan Yu Zhu,Dong Jiang Xue,Luo Hong Qun,Li Nian Bing
In this work, a facile and label-free ratiometric sensor is constructed for selective determination of norepinephrine (NE) by coupling second-order scattering (SOS) and fluorescence, two different and independent optical signals. Herein, polyethyleneimine (PEI) dilute solution medium shows an intensive SOS signal without any fluorescence response. Interestingly, NE can be selectively induced by PEI to emit bright fluorescence, and meanwhile causes an observable decrease in the SOS signal due to the interactions between NE and PEI. The simultaneous variation of the two independent signals can be used for ratiometric sensing of NE. Under the optimal conditions, the resultant ratiometric sensor displays high sensitivity and selectivity toward NE by simultaneously monitoring fluorescence and SOS signals with the same excitation wavelength. The proposed sensor exhibits a good linear relationship versus NE concentration in the range of 10.0 nM–45.0 μM with a detection limit of 2.0 nM ( S / N = 3) and has been successfully applied to the determination of NE in real samples without the use of any extra reagent. The combination of fluorescence and SOS signals provides a new scheme for ratiometric sensor design, greatly simplifying experimental procedure and effectively enhancing detection accuracy. Moreover, the proposed analytical strategy further broadens the application of dilute solutions of polymers in research into optical sensor and green analytical chemistry.
Graphical abstract
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高影响因子
MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 6
·1-8
·
IF 5.479
Zhang Yu,Xu Mengjiao,Gao Pan,Gao Wenkai,Bian Zhenfeng,Jia Nengqin
A photoelectrochemical (PEC) method was developed for the determination of dopamine. It is making use of a composite prepared from gold nanoparticles and TiO 2 (type P25) and placed on a fluorine-doped tin oxide (FTO) electrode. The composites are used for photoelectrical detection with improved electron transfer efficiency for photoproduction and with improved photoelectrical conversion efficiency. This is due to the excellent electrical conductivity and surface plasmon resonance absorption by gold nanoparticles, and also by the photocatalytic effect of TiO 2 . Dopamine binds easily to the surface of the composites and acts as an electron donor. This electrode gives a strongly enhanced photocurrent which increases linearly in the 0.1 to 100 μM dopamine concentration range and has a 23 nM detection limit (at S/ N = 3). The electrode was operated over 15 cycles of light-on and light-off states every 20 s under visible-light illumination, and the sensor indicates good stability. In addition, it is selective over several possible interferents including uric acid, L-cysteine, glutathione, ascorbic acid and glucose.
A new gold/P25 composite-based photoelectrochemical sensing scheme for dopamine is described. Under visible light irradiation, the photocurrent response is increased with the increasing concentration of dopamine (DA).
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MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 5
·1-8
·
IF 5.479
Fan Xuexue,Xu Yanan,Sheng Tiandu,Zhao Dongqing,Yuan Haikuan,Liu Fengjiao,Liu Xijian,Zhu Xueyan,Zhang Lijuan,Lu Jie
A surface-graphenized pencil graphite electrode (SGPGE) served as an amperometric sensor for dopamine (DA). It was prepared through a one-step in-situ electrochemical graphene delamination. The graphite particles on the outer surface of the pencil graphite electrode (PGE) were delaminated by controlling the electrochemical delaminating conditions such as the applied anodic voltage and polarization duration, as well as the kind of electrolytes. The best conditions were identified by scanning electron microscopy, Raman spectra, cyclic voltammetry and differential pulse voltammetry (DPV). As a result, the electrode was endowed with an optimum combination of graphene delamination efficiency and electrochemical activity. The electrochemical treatment activates the surface sensing sites and improves the sensing performance. The NaOH-teated anodically graphenized electrode was used to sense dopamine by DPV. The best oxidation voltage of dopamine is at around 0.17 V (vs. SCE). The electrode respondsy to dopamine in the ranges of 0.15 to 45 μM, the detection limit is 8.2 nM (S/ N = 3), and the sensitivity is 20.81 μA μM −1 cm −2 . In real human urine samples, the sensor exhibited detection recoveries of 97.4–98.8% and low relative standard deviations of 3.49–3.92%.
Schematic presentation of a surface-graphenized pencil graphite electrode (SGPGE) for detecting dopamine. It was prepared by a one-step in situ electrochemical graphene delamination.
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SENSORS AND ACTUATORS B-CHEMICAL
·
2018
·
IF 5.667
Mengli Xu,Linyu Wang,Yi Xie,Yonghai Song,Li Wang
Here, a covalent organic framework with multiple redox-active state synthesized by amine-aldehyde condensation reaction between 4,4′,4′'-(1,3,5-triazine-2,4,6-triyl) trianiline and 2,5-dihydroxy terethaldehyde (COF DHTA-TTA ) was used as novel electrochemical sensing and biosensing platform at first time. The COF DHTA-TTA was demonstrated to be two-dimensional nanosheets with highly ordered conjugated structure and uniform mesopores about 3.67 nm. Electrochemical studies revealed that a ratiometric electrochemical sensor could be constructed by using COF DHTA-TTA itself as electroactive materials to determine hydrogen peroxide (H2O2) and pH level based on both current and potential signals. The single electrochemical sensor could monitor H2O2 concentration from 5.66 μM to 400 μM and pH level ranging from 11.0 to 3.0. Considering that the COF DHTA-TTA had good catalytic activity for oxygen reduction reaction in 0.2 M PBS (pH = 7.0), glucose oxidase was further loaded on COF DHTA-TTA via its nanosized pores and abundant active sites originated from N-doped skeleton, and the glucose biosensor exhibited good performances for glucose detection from 1.26 μM to 6.0 mM at −0.30 V, as well as from 0.60 μM to 6.0 mM at −0.53 V. The work provided good examples to construct electrochemical sensors based on redox-active COF.
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TALANTA
·
2018
·
IF 4.244
Xue Han,Ming Han,Lin Ma,Fei Qu,Rong-Mei Kong,Fengli Qu
We present a fluorescence turn-on and colorimetric dual-readout sensing system for the sensitive detection of alkaline phosphatase (ALP) activity via self-assembled gold nanoclusters (AuNCs) based on fluorescence resonance energy transfer (FRET). The positively charged polyallylamine hydrochloride (PAH)-crosslinked AuNCs (PAH-AuNCs) with aggregation-induced enhancement (AIE) characteristics can electrostatically adsorb the negatively charged 2, 6-dichlorophenolindophenol (DCIP). Thus, the fluorescence of PAH-AuNCs can be significantly quenched by the occurrence of FRET from PAH-AuNCs to DCIP. However, the reduction reaction of DCIP from blue to colourless by L -ascorbic acid (AA) which is generated by the ALP catalyse hydrolysis of 2-Phospho- L -ascorbic acid (AAP) disturbs the FRET between PAH-AuNCs to DCIP. The quenched PAH-AuNCs fluorescence can be recovered efficiently. The strategy of first creating AIE-enhanced PAH-AuNCs, followed by the effective FRET manipulation, is an important contribution to the sensitive detection of ALP. More importantly, the distinct colorimetric signal change can be used to visually distinguish the presence of ALP. More importantly, the distinct colorimetric signal change can be used to visually distinguish the presence of ALP. Good linear relationships of fluorescence and colorimetric sensing towards ALP were obtained in the range from 0.5 to 100 U/L, and the detection limits were 0.2 U/L and 0.5 U/L, respectively. In addition, the proposed FRET sensing system was applied to the detection of ALP in human serum samples with satisfactory results. The simple and efficient sensing approach proposed here has the potential to promote the development of chemo/biodetection methods using fluorescence and colorimetric dual-readout.
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ANALYTICA CHIMICA ACTA
·
2018
·
IF 5.123
Nan Wang,Yashuang Hei,Jingju Liu,Mimi Sun,Tianze Sha,Mehboob Hassan,Xiangjie Bo,Yingna Guo,Ming Zhou
In this work, the low-cost carbon nanorods assembled hierarchical meso-macroporous carbons networks aerogels (CNs-HMCNAs) was environment-friendly synthesized from a cheap and abundant biomass of apples ( Malus pumila Mill ) for the first time. The biomass of apples derived CNs-HMCNAs exhibited the unique hierarchical meso-macroporous structure with large specific surface area and high density of edge defective sites. At the CNs-HMCNAs modified GCE (CNs-HMCNAs/GCE), the electron transfer between the glassy carbon electrode (GCE) and the ascorbic acid (AA) (or hydrogen peroxide (H 2 O 2 )) was effectively enhanced, and thus induced a low overvoltage for AA electrooxidation (or H 2 O 2 electroreduction). As an electrochemical AA (or H 2 O 2 ) sensor, the CNs-HMCNAs/GCE exhibited wider linear range, lower detection limit, higher sensitivity and stability than GCE and the carbon nanotubes modified GCE (CNTs/GCE). In particular, the CNs-HMCNAs/GCE showed great potential feasibility in the practical determination of AA (in AA injection, Vitamin C tablet and kiwi juice) or H 2 O 2 (in human urine, milk and beer).
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BIOSENSORS & BIOELECTRONICS
·
2018
·
IF 8.173
Zihua Wang,Yuan Chen,Wenhao Dong,Jiexin Zhou,Bingkai Han,Jun Jiao,Lintao Lan,Peng Miao,Qiang Chen
In this work, carboxylated multi walled carbon nanotubes (CMWCNTs) were firstly prepared and functionalized with poly- L -histidine (PLH), which were then chelated with copper (II) ions to from the nanocomposites of Cu(II)-PLH-CMWCNTs. The nanocomposites could be exploited as an efficient mimic enzyme for sensitive electrochemical detection of salvianic acid A (SAA). Cu(II)-PLH-CMWCNTs owned good charge transfer property and excellent synergetic catalytic effect between the overoxidized imidazole groups and the copper redox-active units. Therefore, highly sensitive electrochemical response to SAA was achieved under optimum experimental conditions. A good linear relationship between differential pulse voltammetry (DPV) peak current and the SAA concentration was established in the range of 0.4–1000 μM. A low detection limit of 0.037 μM and a sensitivity of 0.27 μA μM −1 cm −2 were achieved. The developed biosensor also had advantages of good repeatability, stability and high selectivity, thus, it was successfully applied to the determination of SAA in real samples with satisfactory results, which may have great potential for further exploitation of electroanalysis applications.
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BIOSENSORS & BIOELECTRONICS
·
2018
·
IF 8.173
Han Yang,Jie Zhao,Meijia Qiu,Peng Sun,Dongxue Han,Li Niu,Guofeng Cui
In this work, Pt nanoparticles modified nanoporous AuSn(Pt@NP-AuSn) alloy on Ni buffered flexible carbon fiber paper (CFP) is fabricated by a simple replacement reaction in which NP-AuSn is fabricated by controllable dealloy of electrodeposited Au-Sn alloy films. The as prepared Pt@NP-AuSn/Ni/CFP possesses hierarchical pore structure , high specific surface area and excellent catalytic activity . Due to the bi-functions of both the large surface area of nanoporous metal and macroporous of carbon fiber paper facilitating mass transfer, the Pt@NP-AuSn/Ni/CFP shows high sensitivity of detecting ascorbic acid (AA), dopamine (DA) and uric acid (UA), with sensitivities of 0.14 μA μM −1 cm −2 , 15.23 μA μM −1 cm −2 , 0.28 μA μM −1 cm −2 under the concentration ranging from 200 to 2000 μM, 1–10 μM, and 25–800 μM for AA, DA and UA, respectively. Further, the Pt@NP-AuSn/Ni/CFP possesses long-term stability of sensing AA, DA and UA and presents great anti-interference towards a variety of common compounds in body fluid. All of these results manifest the Pt@NP-AuSn/Ni/CFP can be a promising candidate for the application of the electrochemical sensor for simultaneous detection of AA, DA and UA.
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ACS Applied Materials & Interfaces
·
2018
·
IF 8.097
Xiao Liu,Wei Qi,Yuefei Wang,Daiwu Lin,Xuejiao Yang,Rongxin Su,Zhimin He
A facile approach was reported to establish mimic multienzyme systems with hierarchically porous (HP) biomimetic metal–organic frameworks (MOFs) and natural enzymes for tandem catalysis. The hierarchically porous MOF HP-PCN-224(Fe) with peroxidase-like activity and tunable hierarchical porosity was synthesized via a modulator-induced strategy. HP-PCN-224(Fe) not only acts as the enzyme-immobilization matrix but also as an effective enzyme mimic, which could cooperate with the immobilized natural enzyme to catalyze the cascade reactions. The mimic multienzyme systems were used for the efficient colorimetric detection of a series of biomolecules, including glucose and uric acid. This work displays the great potential to construct highly functional biocatalysts by integrating the merits of both natural enzymes and MOF mimics, which are promising for applications in biosensing and biomimetic catalysis.
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Nanoscale
·
2018
·Vol. 10
·期 37
·17834-17841
·
IF 7.233
Wenxiang Xu,Jingqin Chen,Shan Sun,Zhongdi Tang,Kai Jiang,Liang Song,Yuhui Wang,Chengbo Liu,Hengwei Lin
Photoacoustic imaging (PAI) has emerged as a promising clinical technology, thanks to its high-resolution in deep tissues. However, the lack of specificity towards analytes limits further application of the PA probe in molecular imaging. To this end, we herein report a PA and fluorescence (FL) dual-modal probe for the selective detection of ascorbic acid (AA). To realize this design, cobalt oxyhydroxide (CoOOH) was adopted as a multifunctional platform (PA contrast agent, FL quencher and specific oxidant to AA) and hybridized with red-emissive carbon dots (RCDs). In the presence of AA, CoOOH is reduced to Co2+ and meanwhile releases RCDs, resulting in the decrease of PA and recovery of FL signals. We demonstrated the AA detection capabilities of the probe in complicated biological fluids (human serum and urine), living cells, and dual-modal FL/PA imaging in vivo. This work revealed the PAI capacity of CoOOH for the first time, which may inspire researchers to design other CoOOH-based PA probes and further employ RCDs in biology and the clinic.
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ACS Applied Materials & Interfaces
·
2018
·
IF 8.097
Yuqian Liu,Qingsheng Guo,Xiaojun Qu,Qingjiang Sun
The combination of functional nucleic acids and nanomaterials enables the continuous development of hybrid nanosystems that have found wide applications including chemo/biosensing. Herein, we report the supramolecular assembly of a “sesame biscuit”-like superstructural nanosystem based on aptamer, quantum dot (QD), and graphene oxide (GO), and its diverse applications in Pb2+ and pH sensing. The nanosystem was assembled via adsorbing silica-encapsulated green-emitting QD onto the edge of GO by ionic interaction, followed by absorbing aptamer-modified red-emitting QD onto the GO surface via the π-stacking interaction. The nanosystem showed the characteristic of the nonquenched green fluorescence due to silica encapsulation and quenched red fluorescence owing to nanomaterial surface energy transfer. The nanosystem responded to Pb2+/pH in ratiometric fluorescence: the red fluorescence varied upon analyte-driven conformational changes of the aptamer, whereas the green one remained constant. Under optimized conditions, the nanosystem was demonstrated to be capable of quantifying Pb2+ with a detection limit of 11.7 pM, as well as pH with a sensing resolution of 0.1 pH unit. More importantly, the ratiometric nanosystem facilitated visualization of analytes in a distinct “traffic light” manner, which was exemplified by semiquantification of exogenous Pb2+ in living cells. To demonstrate practicality, fluorescent test strips were fabricated by immobilizing the nanosystem on paper. The fluorescent test strips displayed traffic light-type fluorescence color changes, with the capacity for on-site, naked-eye detection of Pb2+ in real samples, as well as point-of-care pH testing in routine urinalysis.
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POLYMER DEGRADATION AND STABILITY
·
2018
·
IF 3.193
Feng Ye,Xiaojie Guo,Haihua Zhan,Jiaxian Lin,Weichong Lou,Xiaotao Ma,Xu Wang
Zinc urate (Zn 3 Ur 2 ) is synthesized by the reaction of uric acid and zinc acetate , and the structure of the complex is confirmed by Elemental analysis (EA), Thermogravimetric analysis (TGA) and Infrared spectroscopy (FTIR). The thermal stability effect of Zn 3 Ur 2 with its assistant thermal stabilizers about calcium stearate, β-diketones and polyols on Poly (vinyl chloride) (PVC) is investigated by TG, Congo red test and Discoloration test. The results show that the thermal stability of PVC is increased significantly after Zn 3 Ur 2 is added. Compared with traditional commercial thermal stabilizer such as ZnSt 2 , Zn 3 Ur 2 can observably delay the “Zinc burning” of PVC and the complete discoloration time is improved to 150 min. This is mainly attributed to the anions in the structure of Zn 3 Ur 2 , which could efficiently absorb the HCl released by PVC and have ability to replace unstable chlorine atoms on structure of PVC. Moreover, the mixing of Zn 3 Ur 2 and calcium stearate (CaSt 2 ) can signally promote the long-term thermal stability of PVC. The thermal stability of PVC reaches the optimal state when the ratio of CaSt 2 /Zn 3 Ur 2 is 1.8/1.2 and its total black time arrives at 210 min. In addition, an excellent synergistic effect can be observed when CaSt 2 /Zn 3 Ur 2 is combined with other commercial assistant stabilizers. The initial color and long-term stability of PVC containing CaSt 2 /Zn 3 Ur 2 is markedly improved when Dibenzoylmethane (DBM) is added while Pentaerythritol (PER) can only increase its long-term stability.
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危险品化学品经营许可证（带存储）