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催化学报 2011年第11期32卷 1685-1692页

作者： jahan bakhsh raoof Reza OJANI Mehdi BAGHAYERI Electroanalytical Chemistry Research Laboratory Department of Analytical Chemistry Faculty of Chemistry Mazandaran University Babolsar 47416-95447 Iran

A carbon paste electrode (CPE) modified with ferrocene carboxylic acid (FcCA) and TiO2 nanoparticles was constructed by incorporating TiO2 nanoparticles and ferrocene carboxylic acid into the carbon paste matrix. The electrochemical behavior of captopril (CAP) at the surface of the modified electrode was investigated using electroanalytical methods. The modified electrode showed excellent electrocatalytic activity for the oxidation of CAP in aqueous solutions at physiological pH values. Cyclic voltammetric curves showed that the oxidation of CAP at the surface of the modified electrode reduced its overpotential by more than 290 mV. The modified electrode was used for detecting captopril using cyclic voltammetry and square wave voltammetry techniques. A calibration curve in the range of 0.03 to 2400 μmol/L was obtained that had a detection limit of 0.0096 μmol/L (3?) under the optimized conditions. The modified electrode was successfully used for the determination of captopril in pharmaceutical and biological samples.

关键词： electrocatalysis modified electrode nano-TiO2 ferrocene carboxylic acid captopril cyclic voltammetry

Efficient nonenzymatic hydrogen peroxide sensor in acidic media based on Prussian blue nanoparticles-modified poly(o-phenylenediamine)/glassy carbon electrode

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Chinese Chemical Letters 2016年第3期27卷 481-486页

作者： Reza Ojani Parisa Hamidi jahan-bakhsh raoof Electroanalytical Chemistry Research Laboratory Faculty of ChemistryUniversity of Mazandaran

The Prussian blue nanoparticles（PBNPs） were prepared by a self-assembly process, on a glassy carbon（GC） electrode modified with a poly（o-phenylenediamine）（Po PD） film. The stepwise fabrication process of PBNPs-modified Po PD/GCE was characterized by scanning electron microscopy（SEM） and electrochemical impedance spectroscopy. The prepared PBNPs showed an average size of 70 nm and a homogeneous distribution on the surface of modified electrodes. The PBNPs/Po PD/GCE showed adequate mechanical, electrochemical stability and good sensitivity in comparison with other PB based H2O2 sensors. The present modified electrode exhibited a linear response for H2O2 reduction over the concentration range of 1–58.22 mmol L ^-1with a detection limit of ca. 0.8 mmol L ^-1（S/N = 3）, and sensitivity of 3187.89 m A（mol L ^-1） ^-1cm ^-2using the amperometric method. This sensor was employed for the H2O2 determination in real sample and also exhibited good interference resistance and selectivity.

关键词： Self-assembly Prussian blue nanoparticles Hydrogen peroxide Sensor

Electrocatalytic oxidation of thiosulfate at 2,7-bis(ferrocenylethyl)-fluoren-9-one-modified carbon paste electrode(2,7-BFEFMCPE):Application to the catalytic determination of thiosulfate in real sample

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Chinese Chemical Letters 2010年第12期21卷 1462-1466页

作者： jahan bakhsh raoof Reza Ojani Hassan Karimi-Maleh Electroanalytical Chemistry Research Laboratory Department of Analytical ChemistryFaculty of ChemistryUniversity of MazandaranBabolsarIran

Electrocatalytic oxidation of thiosulfate at the 2,7-BFEFMCPE occurs at a potential about 460 mV less positive than that unmodified carbon paste *** diffusion coefficient（=5.6×10^-5）cm^2 s^-1）,the kinetic parameters such as electron transfer coefficient,（=0.5） and kh（=1.21×10^-3 cm s^-1） of thiosulfate oxidation at the surface of,2,7-BFEFMCPE were *** electrocatalytic oxidation peak current of thiosulfate showed two linear dynamic ranges（0.0006-0.009 mmol/L and 0.009- 0.900 mmol/L） and a detection limit of 0.00015 mmol/*** method was also examined as a new electrochemical sensor for the determination of thiosulfate in real sample.

关键词： 2,7-Bis(ferrocenylethyl)-fluoren-9-one Thiosulfate Electrocatalysis Cyclic voltammetry Differential pulse voltammetry

Celestine blue as a new indicator in electrochemical DNA biosensors

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Science China Chemistry 2016年第1期59卷 128-134页

作者： Ezat Hamidi-Asl jahan bakhsh raoof Abdolraoof Samadi Meibodi Zahra Haghnavaz Bazgir Eletroanalytical Chemistry Research Laboratory Department of Analytical Chemistry Faculty of Chemistry University of MazandaranBabolsarIran Spectroscopic Research Laboratory Department of Analytical ChemistryFaculty of Chemistry University of MazandaranBabolsarIran

Celestine blue(CB)was introduced as a new electroactive indicator in DNA *** interaction of CB with DNA was investigated by electrochemical and spectroscopic *** effect of buffer kind and p H on the electrochemical behavior of CB was *** peak currents of CB were linearly related to DNA concentration in the range of 5.0×10^(-9) to 1.0×10^(-7)mol/*** detection limit of this approach was 4.76×10^(-10) mol/*** on spectrometry data a hypochromic effect was observed in UV-Vis spectra of CB with increasing DNA *** results illustrate the possible interaction mode between CB and DNA is electrostatic binding.

关键词： celestine blue differential pulse voltammetry DNA biosensor electroactive indicator

银掺杂聚(2-氨基二苯胺)修饰碳糊电极作为一种简单有效的电催化剂用于甲醛氧化（英文）

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催化学报 2014年第9期35卷 1565-1570页

作者： Reza Ojani Saeid Safshekan jahan-bakhsh raoof Electroanalytical Chemistry Research Laboratory Faculty of Chemistry University of Mazandaran Babolsar Iran

This work describes the promising activity of silver nanoparticles on the surface of a poly(2‐amino diphenylamine) modified carbon paste electrode(CPE) towards formaldehyde oxidation. Electro‐deposition of the conducting polymer film on the CPE was carried out using consecutive cyclic voltammetry in an aqueous solution of 2‐aminodiphenylamine and HCl. Nitrogen groups in the polymer backbone had a Ag ion accumulating effect, allowing Ag nanoparticles to be electrochemi‐cally deposited on the surface of the electrode. The electrochemical and morphological characteris‐tics of the modified electrode were investigated. The electro‐oxidation of formaldehyde on the sur‐face of electrode was studied using cyclic voltammetry and chronoamperometry in aqueous solu‐tion of 0.1 mol/L Na OH. The electro‐oxidation onset potential was found to be around-0.4 V, which is unique in the literature. The effect of different concentrations of formaldehyde on the electrocat‐alytic activity of the modified electrode was investigated. Finally, the diffusion coefficient of formal‐dehyde in alkaline media was calculated to be 0.47 × 10–6 cm2/s using chronoamperometry.

关键词：修饰碳糊电极氨基二苯胺银纳米粒子电氧化电极对甲醛循环伏安法修饰电极

A rapid synthesis of high surface area PdRu nanosponges:Composition-dependent electrocatalytic activity for formic acid oxidation

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Journal of Energy Chemistry 2017年第4期26卷 703-711页

作者： Ehteram Hasheminejad Reza Ojani jahan bakhsh raoof Electroanalytical Chemistry Research Laboratory Department of Analytical ChemistryFaculty of ChemistryUniversity of Mazandaran47416-95447BabolsarIran

Here, Pd Ru nanoparticle networks（NPNs） with various compositions were synthesized through an inexpensive method in water as a green solvent, at different ratios of the H;PdCl;and RuCl;precursors. This is a fast, room temperature and surfactant free strategy which is able to form high surface area metal nanosponges with a three-dimensional（3D） porous structure. The structure of as-prepared nanosponges was characterized using the techniques of field emission scanning electron microscopy（FESEM）, energy dispersive spectroscopy（EDS） and cyclic voltammetry（CV）. Then, the electrocatalytic activities of Pd Ru NPNs towards formic acid oxidation were examined by electrochemical measurements including CV,chronoamperometry, and electrochemical impedance spectroscopy（EIS）. Based on studies, it was found that the current density of formic acid oxidation（FAO） is strongly dependent on the composition of Pd Ru NPNs. The best performance was realized for Pd;Ru;NPNs compared to monometallic Pd counterpart and other bimetallic NPNs which might be ascribed to the role of Ru in the decrease of CO adsorption strength on the catalyst and consequently the priority of formic acid oxidation through the direct pathway. The Pd;Ru;NPNs also showed the maximum current density and stability in chronoamperometric measurements. In addition, comparative studies were performed between as-prepared NPNs and CNTs-supported Pd nanoparticles（Pd NPs/CNTs）. The present results demonstrated the unique structural advantages of NPNs compared to individual Pd NPs supported on the CNT which leads to the promising performance of NPNs as supportless catalysts for the oxidation of formic acid.

关键词： Palladium–ruthenium Nanosponge Nanoparticle networks Methanol oxidation Green synthesis

用聚(L-蛋氨酸)/纳米金修饰玻碳电极同时灵敏检测多巴胺和尿酸(英文)

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催化学报 2014年第3期35卷 423-429页

作者： Reza Ojani jahan-bakhsh raoof Ali Asghar Maleki Saeid Safshekan Electroanalytical Chemistry Research Laboratory Faculty of ChemistryUniversity of Mazandaran

A novel electrochemical sensor was fabricated by electrodeposition of gold nanoparticles on a poly(L-methionine)(PMT)-modified glassy carbon electrode(GCE) to form a nano-Au/PMT composite-modified GCE(nano-Au/PMT/GCE).Scanning electron microscopy and electrochemical techniques were used to characterize the composite *** modified electrode exhibited considerable electrocatalytic activity towards the oxidation of dopamine(DA) and uric acid(UA) in phosphate buffer solution(pH = 7.00).Differential pulse voltammetry revealed that the electrocatalytic oxidation currents of DA and UA were linearly related to concentration over the range of 5.0 ×10–8 to 10–6 mol/L for DA and 7.0 × 10–8 to 10–6 mol/L for *** detection limits were 3.7 × 10–8mol/L for DA and 4.5 × 10–8 mol/L for UA at a signal-to-noise ratio of *** to our experimental results,nano-Au/PMT/GCE can be used as a sensitive and selective sensor for simultaneous determination of DA and UA.

关键词： L-蛋氨酸玻碳电极多巴胺金纳米颗粒尿酸电化学传感器扫描电子显微镜磷酸盐缓冲溶液

Pt/十六烷基三甲基溴化铵纳米聚集体修饰玻碳电极促进析氢(英文)

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催化学报 2015年第2期36卷 216-220页

作者： jahan-bakhsh raoof Sayed Reza Hosseini Seyedeh Zeinab Mousavi-Sani Electroanalytical Chemistry Research Laboratory Department of Analytical Chemistry Faculty of Chemistry University of Mazandaran Nanochemistry Research Laboratory Faculty of Chemistry University of Mazandaran

A novel, cost-effective, and simple electrocatalyst based on a Pt-modified glassy carbon electrode(GCE), using cetyltrimethylammonium bromide(CTAB) as a cationic surfactant, is reported. Amphiphilic CTAB molecules were adsorbed on GCE by immersion in a CTAB solution. The positively charged hydrophilic layer, which consisted of small aggregates of average size less than 100 nm,was used for accumulation and complexation of [PtCl2. anions by immersing the electrode in Ksolution. The modified electrode was characterized using scanning electron microscopy,energy-dispersive X-ray spectroscopy, impedance spectroscopy, and electrochemical methods. The electrocatalytic activity of the Pt particles in the hydrogen evolution reaction(HER) was *** results show that the CTAB surfactant enhances the electrocatalytic activity of the Pt particles in the HER in acidic solution.

关键词：十六烷基三甲基溴化铵玻碳电极析氢反应聚集体纳米阳离子表面活性剂扫描电子显微镜 CTAB

银纳米颗粒的合成及用于抗癌药氟他胺的电化学检测（英文）

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催化学报 2015年第3期36卷 439-445页

作者： Farzaneh Ahmadi jahan bakhsh raoof Reza Ojani Mehdi Baghayeri Moslem Mansour Lakouraj Hamed Tashakkorian Electroanalytical Chemistry Research Laboratory Department of Analytical ChemistryFaculty of ChemistryUniversity of MazandaranBabolsarIran Department of Organic Chemistry Faculty of ChemistryUniversity of MazandaranBabolsarIran

Ag nanoparticles were synthesized on the surface of a glassy carbon electrode modified with p‐tert‐butylcalix[4]arene and p‐tert‐butylcalix[6]arene by the deposition of Ag+ at an open circuit potential followed by the electrochemical reduction of the Ag+.The presence of the calixarene layer on the electrode surface controlled the particle size and prevented *** voltam‐metry showed that the Ag nanoparticles on the modified glassy carbon electrode had good catalytic ability for the reduction of *** effects of calixarene concentration,potential applied for the reduction of Ag+,number of calixarene layers,and p H value on the electrocatalytic activity of the Ag nanoparticles were *** modified electrode had a linear range in differential pulse voltammetry of 10-1000 μmol/L with a detection limit of 9.33 μmol/L for flutamide at an S/N = *** method was applied to the detection of flutamide in practical samples.

关键词：电化学检测银纳米粒子氟他胺抗癌药物合成 Ag纳米粒子修饰玻碳电极电化学还原

Developing a Nano-Biosensor for DNA Hybridization Using a New Electroactive Label

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Chinese Journal of Chemistry 2011年第11期29卷 2541-2551页

作者： raoof, jahan bakhsh Ojani, Reza Ebrahimi, Maryam Hamidi-Asl, Ezat Electroanalytical Chemistry Research Laboratory Department of Analytical Chemistry Faculty of Chemistry University of Mazandran Babolsar Iran

Development of electrochemical DNA hybridization biosensors based on carbon paste electrode （CPE） and gold nanoparticle modified carbon paste electrode （NGMCPE） as transducers and ethyl green （EG） as a new electroac- tive label is described. Electrochemical impedance spectroscopy and cyclic voltammetry techniques were applied for the investigation and comparison of bare CPE and NGMCPE surfaces. Our voltammetric and spectroscopic studies showed gold nanoparticles are enable to facilitate electron transfer between the accumulated label on DNA probe modified electrode and electrode surface and enhance the electrical signals and lead to an improved detection limit. The immobilization of a 15-mer single strand oligonucleotide probe on the working electrodes and hybridiza- tion event between the probe and its complementary sequence as a target were investigated by differential pulse voltammetry （DPV） responses of the EG accumulated on the electrodes. The effects of some experimental variables on the performance of the biosensors were investigated and optimum conditions were suggested. The selectivity of the biosensors was studied using some non-complementary oligonucleotides. Finally the detection limits were calculated as 1.35×10^-10 mol/L and 5.16×10^-11 mol/L on the CPE and NEGCPE, respectively. In addition, the bio-sensors exhibited a good selectivity, reproducibility and stability for the determination of DNA sequences.

关键词： ethyl green hybridization detection DNA recognition gold nanoparticle modified carbon paste elec- trode biosensors nucleotides