Electrochemical determination of ciprofloxacin using glassy carbon electrode modified with CoFe2o4-MWCNT

CoFe2O4 nanostructures composed of spherical-like were obtained by sol-gel method with glucose as template and combine with MWCNT and composed CoFe2O4-MWCNT heterostructure. The crystal Structure, phase composition, morphology and magnetic properties of CoFe2O4/MWCNT heterostructure were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and vibrating sample magnetometers (VSM), A pure phase of well crystallized CoFe2O4 nanostructures, with average size of 60 nm, could be readily synthesized at present glucose. The modified glassy carbon (GC) electrode with CoFe2O4-MWCNT heterostructure was used to determine the ciprofloxacin concentration. A cyclic voltammetric technique was used for comparison between the unmodified and modified electrodes. The fabricated modified electrode shows linear response for detection of ciprofloxacin at two linear range of 0.1-1 µM and 1-30 µM with a detection limit of 0.036 µM. © 2019 by CEE (Center of Excellence in Electrochemistry)

Synthesis of ytterbium tungstate with excellent pseudocapacitive behavior and a high cycling stability material for supercapacitors

Nanoparticles of ytterbium tungstate prepared through the direct addition of an Yb3+ solution to a tungstate solution, were computed through Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS). Further the supercapacitive characteristics of the nanoparticles, as a potential material for constructing electrodes, were evaluated through cyclic voltammetry (CV), galvanostatic charge/discharge (GCD) and electrochemical impedance spectroscopy (EIS). Electrodes made of the Yb2(WO4)3 had a specific capacitance (SC) value of 336 F g-1 in a 2.0 M H2SO4 solution at a potential scan rate of 2 mV s-1; and 298 F g-1 at a current density of 1 A g-1 based on GCD tests. The electrodes also revealed to have a 95.8 cycling durability after 4000 potential cycles. © 2020 by CEE (Center of Excellence in Electrochemistry)

Synthesis, Characterization and Investigation Magnetic and Photovoltaic Properties of FeVO 4 Nanoparticles

INTRODUCTION In the past few decades, the studies of nanoparticles system have been extensively a subject of continue interest in chemistry, physic, and other field

Specific fluorometric assay for direct determination of amikacin by molecularly imprinting polymer on high fluorescent g-C 3 N 4 quantum dots

Here, a specific and reliable fluorometric method for the rapid determination of amikacin was developed based on the molecularly imprinting polymer (MIP) capped g-C 3 N 4 quantum dots (QDs). g-C 3 N 4 QDs were obtained by facile and one-spot ethanol-thermal treatment of bulk g-C 3 N 4 powder and showed a high yield fluorescence emission under UV irradiation. The MIP layer was also created on the surface on QDs, via usual self-assembly process of 3-aminopropyl triethoxysilane (APTES) functional monomers and tetraethyl ortho-silicate (TEOS) cross linker in the presence of amikacin as template molecules. The synthesized MIP-QDs composite showed an improved tendency toward the amikacin molecules. In this state, amikacin molecules located adjacent to the g-C 3 N 4 QDs caused a remarkable quenching effect on the fluorescence emission intensity of QDs. This effect has a linear relationship with amikacin concentration and so, formed the basis of a selective assay to recognize amikacin. Under optimized experimental conditions, a linear calibration graph was obtained as the quenched emission and amikacin concentration, in the range of 3�400 ng mL �1 (4.4�585.1 nM) with a detection limit of 1.2 ng mL �1 (1.8 nM). The high selectivity of MIP sites as well as individual fluorescence properties of g-C 3 N 4 QDs offers a high specific and sensitive monitoring method for drug detection. The method was acceptably applied for the measurement of amikacin in biological samples. © 2019 Elsevier B.V

Synthesis and characterization of Sm2(MoO4)3, Sm2(MoO4)3/GO and Sm2(MoO4)3/C3N4 nanostructures for improved photocatalytic performance and their anti-cancer the MCF-7 cells

Samarium molybdate nanoparticles (Sm2(MoO4)3) were prepared through a hydrothermal procedure and were used to form various composites with graphene oxide (GO) and carbon nitride (C3N4). The changes in the dimensions and morphology of the products were prepared using template agents like cetyltrimethyl ammonium bromide (CTAB), Sodium dodecyl sulfate (SDS) (�90), Triton X-100 (90), Polyvinyl alcohol (95), Ethylene glycol (�99), and polyvinylpyrrolidone (PVP). DRS analysis indicated band gap for the Sm2(MoO4), Sm2(MoO4)3/GO, and Sm2(MoO4)3/C3N4 as 3.75, 3.15, and 3.4 respectively. The characteristics of the prepared nanostructures were studied through X-ray diffraction (XRD), energy dispersive X-ray (EDX), and scanning electron microscopy (SEM). Finally, the activity of the prepared Sm2(MoO4)3 as photo-catalysts for the degradation of different organic dyes such as methyl orange (MO), methylene blue (MB), and rhodamine B (Rh B) was evaluated. The photocatalytic property of Sm2(MoO4)3/C3N4 and Sm2(MoO4)3/GO for the degradation of MO, was obtained. Based on the empirical data Sm2(MoO4)3/C3N4 had the strongest photodegradation effect as compared to the other compounds tested after around 40 min. BET analysis revealed that the specific surface area of the Sm2(MoO4)3 nanocomposite prepared using C3N4 is 15 times that of in the absence of C3N4. Also, the cytotoxicity of synthesized samples was evaluated using MTT assay against human cell lines MCF-7 (cancer), and its IC50 was about 125 mg/L. © 202

A modified sensitive carbon paste electrode for 5-fluorouracil based using a composite of praseodymium erbium tungstate

This paper describes the modification of a modified carbon paste electrode (CPE) using nanoparticles of praseodymium erbium tungstate (Pr:Er). The modified electrode was used for the sensitive voltammetric detection of an anticancer drug (5-fluorouracil (5-FU)) using. The modified-CPE was evaluated using cyclic voltammetry (CV), square wave voltammetry (SWV) and electrochemical impedance spectroscopy (EIS) and the resulting data showed the irreversible 5-fluorouracil oxidation peak around 1.0 V vs. Ag/AgCl. Some key parameters such as pH, the amount of the modifier, potential amplitude, step potential and frequency were studied and optimized. The square wave voltammetry (SWV) analytical calibration curve was linear in the range of 0.01�50 μM, with a detection limit of 0.98 nM analyses. The electron transfer coefficient (α) was also determined to be 0.76. The analyte concentration was also determined in pharmaceutical formulations and recovery percentages were found to be in the range of 96�102. The sensor had good reproducibility and repeatability with acceptable RSD values of 3.6, and 1.02 and a rather long-term stability of around one month. The as-synthesized nanoparticles were also characterized using FESEM, TEM, FTIR and XRD techniques. © 2020 Elsevier B.V

Sonochemical synthesis of ErVO4/MnWO4 heterostructures: Application as a novel nanostructured surface for electrochemical determination of tyrosine in biological samples

Present strategy introduces a novel method established for the synthesis of spherical shape ErVO4/MnWO4 heterostructures by a sonochemical method. This heterostructures with optima morphology can be synthesized by changing power and time ultrasound irradiation without any capping agent. BET analysis revealed that ErVO4/MnWO4 prepared in the presence of ultrasonic procedure has 75 times specific surface area as much as that of those was produced in the absence of ultrasonic rays. A variety of analyses (i.e., BET, XRD, TEM, EDS, FT-IR, and SEM) were applied for characterization of the ErVO4/MnWO4. Next, a selective and sensitive nanostructured sensor based on ErVO4/MnWO4 nanocomposite modified carbon paste electrode (ErVO4/MnWO4/CPE) was constructed for electrochemical detection of tyrosine (Tyr). The electrochemical characterizations were performed using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV). Compared with the unmodified CPE, the oxidation peak current was significantly enhanced for Tyr. The impact of effective parameters on voltammetric response of Tyr was analyzed with design of experiments (DOE) and response surface methodology (RSM). Under the optimized conditions, the oxidation peak current of Tyr was linear over a range of 0.08�400.0 μM with a detection limit of 7.7 nM. Finally, the usage of the proposed method was confirmed by the recovery tests of Tyr in biological samples. © 201

Electrochemical determination of the antipsychotic medication clozapine by a carbon paste electrode modified with a nanostructure prepared from titania nanoparticles and copper oxide

A nanostructure was prepared from titania nanoparticles and copper oxide (TiO2NP@CuO) and used to modify a carbon paste electrode (CPE). The modified CPE is shown to enable sensitive voltammetric determination of the drug clozapine (CLZ). The sensor was characterized by various techniques and some key parameters were optimized. Under the optimum conditions and at a working potential of 0.6 V (vs. Ag/AgCl), the modified CPE has two linear response ranges, one from 30 pmol L�1 to 4 nmol L�1 of CLZ, the other from 4 nmol L�1 to 10 μmol L�1. The detection limit is as low as 9 pM. The transfer coefficient (α) and catalytic rate constant (kcat) were calculated and the reliability of the sensor was estimated for CLZ sensing in real samples where it gave satisfactory results. Figure not available: see fulltext.. © 2019, Springer-Verlag GmbH Austria, part of Springer Nature

Optimization and detailed stability study on coupling of CdMoO4 into BaWO4 for enhanced photodegradation and removal of organic contaminant

BaWO4 nanoparticles and BaWO4/CdMoO4 nanocomposites were synthesized by eco-friendly method at low temperature. The effects of various capping agents such as glucose, fructose, lactose, and starch on the morphology and particle size of BaWO4/CdMoO4 nanocomposites were investigated. The nanocluster was obtained with glucose and Ba2+ to capping agent molar ratio of (1:2). BaWO4/CdMoO4 nanocomposites were analyzed through techniques including, XRD, FT-IR, VSM, TEM, PL, FESEM, UV�vis, and EDX. According to the BET results, in the presence of glucose as the capping agent, surface area increased from 13.781 m2/g to 122.22 m2/g. Furthermore, adding CdMoO4 nanoparticles to BaWO4 causes optical properties and photocatalytic activity of BaWO4 to improve. Moreover, the effects of several factors such as BaWO4/CdMoO4 nanocomposites concentration and its particle size and difference dyes on the photocatalytic performance of BaWO4/CdMoO4 nanocomposites were studied under visible light. © 2018 King Saud Universit

Eco-friendly synthesis of PbTiO3 nanoparticles and PbTiO3/carbon quantum dots binary nano-hybrids for enhanced photocatalytic performance under visible light

PbTiO3 nanoparticles, carbon quantum dots CQDs and their composite (i.e. PbTiO3/CQDs) were prepared and studied using XRD, FT-IR, VSM, TEM, BET, PL, FESEM, UV�Vis, and EDX. Designing highly-effective PbTiO3/CQDs binary nano-hybrids include several fascinating properties of visible light, biocompatibility, eco-friendly response and good durability. Various composites containing different amounts of CQDs were prepared, and the effects of catalysts on enhancing the photocatalytic activity of PbTiO3 nanoparticles in the resulting binary nano-hybrid have been investigated. Test experiments indicated that PbTiO3 nanoparticles could remove only 53 of Rh B, while PbTiO3/5CQDs binary nano-hybrids reached a removal maximum of 100. Further the removal of different dyes using the PbTiO3/CQDs binary nano-hybrids has been evaluated and the removal mechanism has also been discussed. © 2018 Elsevier B.V