The Experts below are selected from a list of 327 Experts worldwide ranked by ideXlab platform
Shouzhuo Yao - One of the best experts on this subject based on the ideXlab platform.
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a novel biomimetic nanoenzyme based on Ferrocene Derivative polymer nps coated with polydopamine
Talanta, 2019Co-Authors: Jiayi Yao, Meiling Liu, Youyu Zhang, Yan Sun, Shouzhuo YaoAbstract:Abstract In this paper, Ferrocene Derivative polymer nanoparticles (FcP NPs) with uniform size and good photostability was synthesized using 1,1′-Ferrocene dicarboxylic acid as precursor and methanol as solvent. FcP NPs-PDA was further obtained by coating of polydopamine (PDA) on FcP NPs in tris-HCl (pH=8.5) buffer solution at room temperature in the presence of dopamine (DA). The structure and morphology of FcP NPs and FcP NPs-PDA were characterized by transmission electron microscope (TEM), ultraviolet-visible spectroscopy (UV–Vis), and infrared radiation (FT-IR). The as-prepared FcP NPs-PDA showed better peroxidase-like activity than FcP NPs, which could catalyze the chromogenic reaction of peroxidase substrate TMB, OPD and ABTS. Based on the high peroxidase-like property of FcP NPs-PDA, a sensitive and convenient means to detect H2O2 has been proposed with TMB as the substrate, which displays wide linear range of 10–600 μM and 600 μM-4 mM with low detection limit of 5 μΜ. Compared with other Fe-containing NPs, such as magnetic materials and noble metal@Fe bimetallic NPs, the preparation approach for FcP NPs-PDA is simple, time and energy saving and environment friendly. This mild and simple synthesis route of FcP NPs-PDA will provide new ideas for the preparation of non-noble metal-based peroxidase-like nanomaterials and widen the applications in the fields of catalytic and analytical chemistry.
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enhanced electrochemical sensitivity towards acetaminophen determination using electroactive self assembled Ferrocene Derivative polymer nanospheres with multi walled carbon nanotubes
Electrochimica Acta, 2018Co-Authors: Yuan Chen, Xiaoying Liu, Wenli Hou, Meiling Liu, Youyu Zhang, Shouzhuo YaoAbstract:Abstract Electron mediators have the ability to facilitate electron acceptance and donation, which can accelerate the electron transfer during the electrochemical process. Few research has been reported about electroactive polymer nanospheres as redox mediators for sensing to date. In this study, we synthesized a new electroactive Ferrocene Derivative polymer nanospheres (FPS) via a facile and self-assembly method. The obtained FPS was characterized by UV–Vis spectra, Fourier transform infrared spectroscopy, transmission electron microscopy and dynamic light scattering. Based on the electroactive property of FPS, a new electrochemical sensor for acetaminophen (AP) based on the nanocomposite of multi-walled carbon nanotubes-ploy-diallyl-dimethyl-ammonium chloride-FPS (MWCNT- PDDA-FPS) was firstly developed. The greatly enhanced electrochemical performance towards AP determination can be obtained owing to the electrocatalysis of electroactive FPS and good conductivity of MWCNT. The AP sensor exhibits a wide sensing linear range from 3 to 1100 μM and the detection limit is 0.6 μM (S/N = 3). Therefore, these Ferrocene Derivative polymer nanospheres may become a new nanomaterial to construct of platforms for bioanalytical and electrochemical immune research in the future.
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a quadruplet electrochemical platform for ultrasensitive and simultaneous detection of ascorbic acid dopamine uric acid and acetaminophen based on a Ferrocene Derivative functional au nps carbon dots nanocomposite and graphene
Analytica Chimica Acta, 2016Co-Authors: Liuqing Yang, Meiling Liu, Youyu Zhang, Na Huang, Shouzhuo YaoAbstract:In this work, a new nanomaterial of thiol functional Ferrocene Derivative (Fc-SH) stabilized Au NPs/carbon dots nanocomposite (Au/C NC) coupling with graphene modified glassy carbon electrode (Fc-S-Au/C NC/graphene/GCE) was fabricated to serve as a quadruplet detection platform for ultrasensitive and simultaneous determination of ascorbic acid (AA), dopamine (DA), uric acid (UA) and acetaminophen (AC). The Au/C NC was synthesized by adding HAuCl4 into carbon nanodots solution without using any additional reductant and stabilizing agent. Then the Fc-SH was utilized as the protective and capping agent to modify the Au/C NC. Transmission electron microscopy (TEM), UV-Vis, Fourier-transform infrared (FT-IR), scanning electron microscopy (SEM), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) were adopted to characterize the morphology and electrochemical properties of the materials and the electrodes. The Fc-S-Au/C NC/graphene/GCE exhibits a synergistic catalytic and amplification effects towards oxidation of AA, DA, UA and AC owing to the existence of the nanomaterial and electron mediator. When simultaneous detection of AA, DA, UA and AC, the oxidation peak potentials of the four compounds on the electrode can be well separated and the peak currents were linearly dependent on their concentrations. The quadruplet detection platform shows excellent linear range and ultrasensitive response to the four components, the detection limits were estimated to be as low as 1.00, 0.05, 0.12 and 0.10 μM (S/N = 3), and the modified electrode exhibits excellent stability and reproducibility. The proposed electrode has been successfully applied to detect of these four analytes in real samples with satisfactory results.
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simultaneous electrochemical determination of dihydroxybenzene isomers based on the hydrophilic carbon nanoparticles and Ferrocene Derivative mediator dual sensitized graphene composite
Electrochimica Acta, 2013Co-Authors: Linping Wang, Youyu Zhang, Yue Meng, Qiong Chen, Jianhui Deng, Shouzhuo YaoAbstract:Abstract A dual sensitized graphene composite decorated with carbon nanoparticles (CNP) and a new Ferrocene-Derivative redox mediator, (4-ferrocenylethyne) phenylamine (FEPA), is prepared by a facile and rapid one-step method. The as-prepared (4-ferrocenylethyne) phenylamine–carbon nanoparticles–graphene (FEPA–CNP–GR) composite coupling with Nafion was used to construct an ultrasensitive electrochemical sensor (Nafion-FEPA–CNP–GR) for simultaneous detection of dihydroxybenzene isomers. It was found that the well-dispersed hydrophilic-type CNP in the composite could improve the water-solubility and the surface area of GR, and exhibit an excellent catalytic activity toward resorcinol (RC) oxidation. Meanwhile, synthesized FEPA served as a good electron-transfer mediator, improved the sensitivity of the sensor, permitted favorable oxidation peak separations between isomers, and reduced the interferences between isomers. FEPA steadily adsorbed on the surface of GR through the π-stacking interaction between the conjugate chain of FEPA and GR, which effectively prevented FEPA mediator leaking from electrode surface. In addition, Nafion used as an immobilization film for eliminate the main interferences in relatively high concentrations, which led to an excellent selectivity. Thus, the proposed method exhibited good stability, sensitivity and selectivity for the simultaneous determination of dihydroxybenzene isomers due to the synergistic effect of CNP, FEPA and GR. Under the optimum conditions, the calibration curves for hydroquinone (HQ), catechol (CC), and RC were obtained in the range of 0.3–90 μmol L −1 , 0.6–100 μmol L −1 and 4–300 μmol L −1 , respectively. The detection limits were found to be 0.1 μmol L −1 for HQ, 0.2 μmol L −1 for CC and 0.7 μmol L −1 for RC based on S/N of 3. The developed method was successfully applied to the simultaneous determination of dihydroxybenzene isomers in synthetic and real samples, and the results are satisfactory.
Xiao Chen - One of the best experts on this subject based on the ideXlab platform.
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construction and transformation of stimuli responsive vesicles from the Ferrocene Derivative supramolecular amphiphiles
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2012Co-Authors: Xiao Chen, Xiu Yue, Dandan Huang, Xudong WangAbstract:Abstract The tough stimuli-responsive vesicles were prepared via electrochemical oxidation on the mixture solution of ferrocenylmethyl-trimethylammonium iodide (FcMI) and sodium deoxycholate (NaDC). The vesicle structure and morphology are characterized respectively by transmission electron microscopy (TEM), dynamic light scattering (DLS) and atomic force microscopy (AFM). The vesicle shells can be clearly observed by TEM with the thickness ranging from several to several tens of nanometers and their outer diameters at the range of 50–200 nm. The formation of vesicular structures is also supported via AFM measurements. Such tough vesicles made up of Ferrocene and deoxycholate blocks are redox-responsive, and their assembly or disassembly behaviors may be controlled by electrochemical methods through the change of Ferrocene states between the neutral hydrophobic and the hydrophilic ferrocenium cation. In addition, the stimuli-responsive vesicles can also be formed from the supramolecular inclusion complex between the Ferrocene blocks and the β-cyclodextrin hosts, which can then be transformed into nanotubes with time. The obtained results are significant for the preparation of smart supramolecular aggregates.
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redox switched transition of vesicles self assembled from aot and Ferrocene Derivative molecules
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2010Co-Authors: Xiao Chen, Bo Jing, Yurong ZhaoAbstract:Abstract Vesicles prepared in an aqueous solution through self-assembly of the oxidized form of N,N-dimethyl-aminomethylFerrocene (Fc + M) and an anionic surfactant, sodium bis(2-ethyl-1-hexyl) sulfosuccinate (AOT), could be reversibly transformed by redox reactions. Adding the hydroquinone as a reducing agent will cause the dissociation of vesicles and change the solution into emulsion. Subsequent oxidization by adding Ce(SO 4 ) 2 will regenerate vesicles. The vesicle structure and morphology were characterized by transmission electron microscopy (TEM) and dynamic light scattering (DLS), respectively and the mean particle size was about 200 nm. The mechanism of vesicle formation and disruption caused by redox reactions is discussed along with the data obtained from cyclic voltammetry (CV) and UV–vis spectroscopy measurements. The redox state changes of the ferrocenyl moiety may influence the noncovalent interactions between FcM and AOT. Meanwhile, the π–π stacking and amphiphilic hydrophobic association are also included during such a redox modulated process. These results provide guidance for the design of surfactant and small molecular systems that permit active control of self-assembly.
Xudong Wang - One of the best experts on this subject based on the ideXlab platform.
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construction and transformation of stimuli responsive vesicles from the Ferrocene Derivative supramolecular amphiphiles
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2012Co-Authors: Xiao Chen, Xiu Yue, Dandan Huang, Xudong WangAbstract:Abstract The tough stimuli-responsive vesicles were prepared via electrochemical oxidation on the mixture solution of ferrocenylmethyl-trimethylammonium iodide (FcMI) and sodium deoxycholate (NaDC). The vesicle structure and morphology are characterized respectively by transmission electron microscopy (TEM), dynamic light scattering (DLS) and atomic force microscopy (AFM). The vesicle shells can be clearly observed by TEM with the thickness ranging from several to several tens of nanometers and their outer diameters at the range of 50–200 nm. The formation of vesicular structures is also supported via AFM measurements. Such tough vesicles made up of Ferrocene and deoxycholate blocks are redox-responsive, and their assembly or disassembly behaviors may be controlled by electrochemical methods through the change of Ferrocene states between the neutral hydrophobic and the hydrophilic ferrocenium cation. In addition, the stimuli-responsive vesicles can also be formed from the supramolecular inclusion complex between the Ferrocene blocks and the β-cyclodextrin hosts, which can then be transformed into nanotubes with time. The obtained results are significant for the preparation of smart supramolecular aggregates.
Leyong Wang - One of the best experts on this subject based on the ideXlab platform.
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ph responsive supramolecular vesicles based on water soluble pillar 6 arene and Ferrocene Derivative for drug delivery
Journal of the American Chemical Society, 2013Co-Authors: Qunpeng Duan, Yu Cao, Tangxin Xiao, Chen Lin, Yi Pan, Leyong WangAbstract:The drug delivery system based on supramolecular vesicles that were self-assembled by a novel host–guest inclusion complex between a water-soluble pillar[6]arene (WP6) and hydrophobic Ferrocene Derivative in water has been developed. The inclusion complexation between WP6 and Ferrocene Derivative in water was studied by 1H NMR, UV–vis, and fluorescence spectroscopy, which showed a high binding constant of (1.27 ± 0.42) × 105 M–1 with 1:1 binding stoichiometry. This resulting inclusion complex could self-assemble into supramolecular vesicles that displayed a significant pH-responsive behavior in aqueous solution, which were investigated by fluorescent probe technique, dynamic laser scattering, and transmission electron microscopy. Furthermore, the drug loading and in vitro drug release studies demonstrated that these supramolecular vesicles were able to encapsulate mitoxantrone (MTZ) to achieve MTZ-loaded vesicles, which particularly showed rapid MTZ release at low-pH environment. More importantly, the cel...
Biswanath Mallik - One of the best experts on this subject based on the ideXlab platform.
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Spectroscopic Studies on the Effect of Some Ferrocene Derivatives in the Formation of Silver Nanoparticles.
Journal of nanoscience and nanotechnology, 2016Co-Authors: Manik Kumar Sanyal, Bipul Biswas, Avijit Chowdhury, Biswanath MallikAbstract:Silver nanoparticles were prepared by microwave assisted method using silver nitrate as precursor in the presence of some Ferrocene Derivatives. The formation of the silver nanoparticles was monitored using UV-Vis spectroscopy. The UV-Vis spectroscopy revealed the formation of silver nanoparticles by exhibiting typical surface plasmon absorption band. The position of plasmon band (406-429 nm) was observed to depend on the nature of a particular Ferrocene Derivative used. TEM images indicated that the nanoparticles were spherical in shape and well-dispersed. Quantum dots (3.2 nm) were prepared by using Ferrocenecarboxylic acid. The surface plasmon absorption band has shown red shift with increasing concentration of Ferrocene Derivative. For different duration of microwave heating time, intensity of absorption spectra in general was found to increase except in presence of Ferrocene carbaldehyde where it decreased. Time-dependent spectra have indicated almost stable position of the surface plasmon band with increasing time of observation confirming that the as prepared silver nanoparticles did not aggregate with lapse of time.
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Spectroscopic studies on the photoinduced changes in some Ferrocene Derivatives in halocarbon solvents
Indian Journal of Physics, 2012Co-Authors: A. Thander, Biswanath MallikAbstract:The photoinduced changes in some Ferrocene Derivatives in halocarbon solvents chloroform and carbon tetrachloride (using deoxygenated solutions) have been investigated under different experimental conditions by monitoring the photoinduced changes in the electronic absorption spectra of the Ferrocene Derivatives in the halocarbon solvents. The spectra were recorded before as well as after photoexcitation of the sample solution by a monochromatic radiation. The results have indicated the photoinduced-charge transfer between a particular Ferrocene Derivative and the halocarbon solvent used. For different values of photoexcitation time (duration), absorption spectra of some of the Ferrocene Derivatives in halocarbon solvents have shown isobestic points. The primary step in the photo process is expected to be the dissociation of the charge transfer state to give the different ions.
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Time-dependent spectral changes of some Ferrocene Derivatives in halocarbon solvents after removal of photoexcitation.
Spectrochimica acta. Part A Molecular and biomolecular spectroscopy, 2009Co-Authors: Biswanath Mallik, A. ThanderAbstract:Abstract The time-dependent changes in the electronic absorption spectra (UV–vis) of some Ferrocene Derivatives in the halocarbon solvents chloroform and carbontetrachloride have been investigated after removal of the photoexcitation by monochromatic radiation (UV) in nitrogen atmosphere. The spectral responses with time after removal of photoexcitations are entirely different for the two solvents. Except for a little exception, it has been observed that in general, in the case of the Ferrocene Derivatives under study the absorbance of new bands appeared due to photoexcitation increases in chloroform and decreases in carbontetrachloride with time after removal of photoexcitation. Our previous study has indicated the photoinduced charge-transfer between a particular Ferrocene Derivative and halocarbon solvent. The results of this present study indicate that some sort of secondary thermal reaction continued even after the removal of photoexcitation and the secondary thermal reaction depends significantly on the Ferrocene Derivative and also the nature of the halocarbon solvent used.
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photoinduced charge transfer between Ferrocene Derivatives and chloroform molecules confined in poly methyl methacrylate thin films
Chemical Physics Letters, 2000Co-Authors: Alfazuddin Thander, Biswanath MallikAbstract:Abstract The changes in the electronic absorption spectra (UV-Vis) (after photoexcitations) of poly(methyl methacrylate) (PMMA) thin films doped with a Ferrocene Derivative and containing chloroform molecules as impurities, have been studied as a function of photoexcitation wavelength (210–750 nm), photoexcitation time (duration), amount of Ferrocene Derivative in the film and amount of chloroform molecules present in the film. Occurrence of photoinduced charge-transfer between some Ferrocene Derivatives and chloroform molecules confined in the PMMA thin films has been observed. The effects of the substitution group (attached to the Ferrocene unit) on the photoinduced changes are discussed.
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Low-frequency electrical current oscillations in the vapor-adsorbed state of some Ferrocene Derivatives
Journal of the Chemical Society Faraday Transactions, 1997Co-Authors: Biswanath Mallik, Aloke Kumar ChakrabortyAbstract:Low-frequency oscillations in electrical (dark, i.e., unilluminated) current as a function of time have been observed in a specific temperature range in samples of some Ferrocene Derivatives, namely Ferrocenecarboxylic acid, Ferrocenecarbaldehyde and acetylFerrocene, with adsorbed ethanol vapor at a pressure of 40 Torr in a sandwich-type cell. The dependence of the oscillatory behavior of current on the applied bias voltage across the electrodes has also been studied at a constant sample cell temperature for each material in the ethanol-vapor-adsorbed state. With increasing bias, increases in both the time interval between two consecutive current peaks (i.e. decrease in frequency of current oscillations) and current peak hight were observed for all of the materials studied. The oscillatory behavior of the current and the temperature at which oscillations occurred depended on the nature of the Ferrocene Derivative. Existing theories of current oscillations in semiconductors have failed to explain the observed low-frequency current oscillations in these organometallic semiconductors. Such current oscillations are possibly associated with some kind of time-dependent phase changes in the Ferrocene Derivative–ethanol system at the sample surface layer.