Search

The development of a sensitive glucose monitoring system is highly important to protect human lives as high blood-glucose level-related diseases continue to rise globally. In this study, a glucose sensor based on polyaniline-bimetallic oxide (PANI-MnBaO2) was reported. PANI-MnBaO2 was electrochemically synthesized on the glassy carbon electrode (GCE) surface. The as-prepared PANI-MnBaO2 was characterized by field emission scanning electron microscopy, Fourier transform infrared spectroscopy, energy dispersive X-ray spectroscopy, cyclic voltammetry, and electrochemical impedance spectroscopy. Glucose sensing on PANI-MnBaO2 is based on the electrocatalytic oxidation of glucose to the glucolactone, which gives oxidation current. The oxidation potential for glucose was 0.83 V, with a limit of detection of 0.06 µM in the linear and in the concentration range of 0.05 µM–1.6 mM. The generated current densities displayed excellent stability in terms of repeatability and reproducibility with fast response. The development of a sensitive glucose sensor as obtained in the current study would ensure human health safety and protection through timely and accurate glucose detection and monitoring. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Natural Fibers is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The synthesis of poly(aniline-co-pyrrole)-Sn(IV)tungstoarsenate((PA-co-Ppy)-STA) nanocomposite cation exchange membrane was prepared through solution casting method in order to ensure the homogeneity of the obtained membrane. The synthesis of the membrane was confirmed by characterization of the nanocomposite membrane by various instrumentation techniques like Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray analysis (EDX), Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD) and Thermogravimetric Analysis (TGA) techniques. The selective detection of Ni(II), having detection limit 1 × 10−9–1 × 10−1 M, the range of pH 5–8 and response time 35 s. The analytical efficacy of this electrode was built up by utilizing it as an indicator in the potentiometric titration. Various experimental parameter studies proved the absorption of Ni(II) on nanocomposite. The method used is a classical method for fabrication of an ion selective electrode and hence is easier and cost effective, other than being most precise for the detection of Ni(II) ions. Along these lines, this novel effort may be a reliable and effective to detect Ni(II) in environmental and biomedical sector in a broad scale. [ABSTRACT FROM AUTHOR]

A novel nanostructure of poly(o-anisidine-co-methyl anthranilate) (poly(Ani-Co-MA) copolymer has been synthesized by chemical oxidative in situ polymerization technique with equal molar proportion of monomers in the presence of sodium dodecylbenzene sulfonic acid (SDBS) surfactant. The synthesized copolymers were characterized by scanning electron microscope (SEM) and X-ray crystallography (XRD), Fourier transform infrared (FTIR), UV-Vis, thermo-gravimetric analysis (TGA), and simultaneous X-ray photoelectron spectroscopy (XPS) study. The ultraviolet visible spectrum shows the π to π∗ transition and n to π∗ transition. XRD diffraction pattern confirms the amorphous nature of poly(Ani-Co-MA)-SDBS composites. The scanning electron microscope image shows the morphology of the copolymer matrix. For the selective detection of Zn+2 cation in neutral phosphate buffer, it was fabricated Zn+2 cation sensor based on glassy carbon electrode (GCE) coated with poly(Ani-co-MA)-SDBS composites as a thin layer with conducting coating binders. The proposed cation sensor has been found to exhibit the inertness in air and chemical environment, long-term stability with good sensitivity, a broad linear dynamic range practically, a reliable reproducibility, short response time, and high electrochemical activity. The sensitivity (0.3560 μA μM−1 cm−2) of Zn+2 cation sensor has been calculated from the slope of the calibration curve. The linearity of the calibration curve is found over the linear dynamic range (LDR) 0.1 nM~0.01 M, and detection limit (DL) is 27.0 ± 1.35 pM at the signal to noise ratio of 3. This novel effort may be considered quite reliable and effective to detect Zn+2 cation in environmental and biomedical sectors on a broad scale. Simultaneously, SDBS doped poly(o-anisidine-co-methyl anthranilate) copolymer composites were measured against medically important organisms Escherichia coli. E. ludwigi, and Bacillus subtilis.ᅟ [ABSTRACT FROM AUTHOR]

Abstract: The polyaniline doped novel anionic gemini surfactant (PANI/GS) was chemically synthesized by a micellar polymerization process and then characterized in details by X-ray powder diffractometry, scanning electron microscopy, and FTIR spectroscopy. The results show the presence of polyaniline in the emeraldine base was formed by doping with gemini surfactant. The thermal properties of the composites were studied by carrying out thermal gravimetric analysis. The PANI/GS were found to be soluble in common organic solvents such as chloroform as well as DMSO. The antibacterial activity of the obtained PANI/GS was also evaluated against Gram positive bacteria Bacillus subtilis, Gram negative bacteria Escherichia coli and antibiotics (Amoxicillin) using the agar plate. The antibacterial study showed that the PANI/GS was found to be most effective against both B. subtilis and E. coli respectively which was significant compared to the amoxicillin. Beside that thin-layer of PANI/GS onto glassy carbon electrode (GCE) was fabricated with conducting 5% nafion coating agents to fabricate a sensitive and selective Cd2+ ionsic sensor in short response time into the phosphate buffer phase. The fabricated cationic-sensor was exhibited higher sensitivity, large-dynamic concentration ranges, long-term stability, and improved electrochemical performances towards Cd2+ ions. The calibration plot is linear (r2, 0.9799) over the large Cd2+ concentration ranges (10.0 nM-1.0 mM). The sensitivity and detection limit is calculated as 2.324 µA µM−1cm−2 and 6.85 nM (signal-to-noise ratio, at a SNR of 3) respectively. These novel efforts are intiated a well-known method for significant cationic sensor development with directly fabricated nanocomposite onto GCE for the detection of hazardous toxins in ecological and environmental fields in huge scales.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Currently, polymer-inorganic composites became inspiration for the design of advanced synthetic materials. Exfoliation/intercalation method was used for the preparation of poly(2-methylaniline)V(III) tungstate nanofiber (POT-VOWO 4 ) composite. The poly(2-methylaniline) into V(III) tungstate was mixed by different volume ratios. A characterization of composite was carried out by XPS, SEM, XRD, FTIR and simultaneous TGA studies. This composite was employed as sensor element in the preparation of ion selective membrane electrode in electrometric titrations by diffusion mechanism. By experiment, it was found that electrode had linear range (1.0 × 10 − 1 M to 6.0 × 10 − 6 M), good Nernstian response of 30.4 mV/decade change of Hg 2 + concentration with working pH range of 3.0–8.0 having short response time of 20s. This electrode was used as indicator electrode for real samples analysis. [ABSTRACT FROM AUTHOR]

A new class of hybrid nanocomposite, poly(aniline-co-o-toluidine)(PANI-Co-OT) tungstomolybdate (TM) was prepared by sol–gel method. The physico-chemical characterization was carried out by Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Ultra Violet Spectroscopy (UV–vis) and simultaneous Thermogravimetric Analysis (TGA) studies. The ion-exchange capacity, distribution studies were also carried out to understand the ion-exchange capabilities. It is highly semiconducting nature in the range of 1.6155 × 10 − 1 –3.0786 × 10 − 1 S/cm. Based on distribution studies, composite was found highly selective for Pb(II) heavy metal ions. Ion-selective membrane electrode was designed for the determination of Pb(ІІ) ions in solutions. The analytical utility of this membrane was established by employing it as an indicator electrode. [ABSTRACT FROM AUTHOR]

A new class of PANI/Sn(II)SiO3/FCNTs nanocomposite was synthesized by mixing polyaniline into the gel of Sn(II)SiO3followed by FCNTs (Polyaniline/Sn(II)SiO3/Functionalized Carbon nanotubes). The physico-chemical characterization was carried out by scanning electron microscope, XRD (X-ray Diffraction), FTIR (Fourier Transform Infrared Spectroscopy), ultraviolet–visible spectroscopy, and simultaneous thermogravimetric analysis studies. The ion-exchange capacity (1.2 meq/g) and distribution studies were also determined to understand the ion-exchange capabilities. The DC electrical conductivity studies revile it in the range of 3–5 × 10−3S/cm. On the basis of distribution studies, ion-selective membrane electrode was designed for Hg(II). The analytical utility of this membrane was established by using it as an indicator electrode in electrometric titrations. [ABSTRACT FROM PUBLISHER]

This study investigated on kinetics of oxidation of captopril by QDC was studied spectrophotometrically in acidic medium along with its mechanistic pathway. Such studies are greatly helpful in gaining an insight into the interaction of metal ions through the study of the mechanistic pathway of CPL in redox reactions. The oxidative product of captopril was found to be captopril disulfide was separated, and identified by FT-IR. A suitable free radical mechanism was proposed. The reaction exhibited first-order kinetics with respect to [oxidant] and fractional order in CPL. Consequently, the interaction between the complex species and CPL is supported kinetic orders of reaction by spectrophotometric verification, positive entropy of activation and the first-order rate constant increased with the increase in the dielectric constant and increase ionic strength of the medium. The reaction constants involved in the mechanism were computed and the overall activation parameters were evaluated which lend support to the proposed mechanism. [ABSTRACT FROM AUTHOR]

The mechanistic investigation of oxidation of levofloxacin(LF) has been studied by chloramine-T(CAT) in aqueous perchloric acidmedium at 25 °C. The reaction followed first-order kinetics withrespect to [CAT], [LF], and [H] in their lower concentrationsrange, tending to zero-order at their higher concentrations. First-orderkinetics with respect to [CAT] was observed for the oxidation of levofloxacin.An increase in perchloric acid concentration increased the rate ofreaction. The effect of added products, ionic strength, and dielectricconstant of the medium was studied on the rate of reaction. The mainproducts were identified by spot test, FT-IR, and NMR. A mechanismwas proposed on the basis of experimental results. The activationparameters with respect to the slow step of the mechanism was evaluated,and the thermodynamic parameters were also determined and discussed. [ABSTRACT FROM AUTHOR]

Direct–contact membrane distillation (DCMD) can be eminent solution for oily wastewater treatment if the membrane provided is slippery and tolerant to low surface tension complex solutions. This study describes preparation of an anti–oil–fouling omniphobic polyethersulfone membrane using fluorinated silica nanoparticles (F–SiO 2 @PES) combined with perfluorodecyl triethoxysilane and polydimethylsiloxane for application against oil–In–water (o/w) emulsions. Feed solutions consist of different concentrations of oil (hexadecane), different charge surfactants (anionic sodium dodecyl benzenesulfonate, non-ionic Tween 20, and cationic hexadecyltrimethylammonium bromide, and salt (NaCl). The hierarchical re -entrant micro structured surface of the omniphobic F–SiO 2 @PES membrane and functional groups are confirmed by atomic force microscopy, scanning electron microscopy, and Fourier-transform infrared spectroscopy. The anti–oil-fouling and anti–wetting performance of omniphobic F–SiO 2 @PES membranes are investigated using contact-angle, sliding angles, DCMD tests with multiple foulants of surfactants. Omniphobic F–SiO 2 @PES membrane exhibited effective anti–oil–fouling and anti–wetting performance against emulsions as no severe fouling and a conductivity rises were evident regardless of surfactant charge and the concentration of components. Flux reduction and rejection rates for the omniphobic F–SiO 2 @PES membranes are in a range of 5–15% (only) and >99%, respectively, for various combinations of feed solution components. Facile fabrication of copper phthalocyanine/reduced graphene oxide composites for efficient photocatalytic reduction of hexavalent chromium. Image 1 • A facile dip coating method was explored for membrane modification. • Hierarchical re -entrant microstructure and slippery surface generated omniphobicity. • Omniphobic F–SiO 2 @PES membrane was obtained for robust application in DCMD. • Omniphobicity was evaluated with multiple and low surface tension feed emulsions. • F–SiO 2 @PES membrane showed anti-oil-fouling and anti-wetting performance in DCMD. [ABSTRACT FROM AUTHOR]

Until now, many efficient catalysts have been reported that are used for the reduction of nitroarenes. However, a catalyst reusability is a challenge that is often faced in practical environment. In this report, we designed a hydrogel composite (CMC-LDH), which act as support and making it possible to address this challenge. In this research work, zinc/aluminum based layered double hydroxides (Zn/Al LDH) have been assembled with carboxymethyl cellulose (CMC) to prepare CMC/LDH hydrogel beads. The CMC/LDH hydrogel beads were prepared by the ionotropic gelation method. For CMC/LDH/Au preparation, the already prepared CMC/LDH beads were kept in gold ion (Au3+) solution, and their subsequent reduction with sodium borohydride (NaBH 4). For the characterization of the prepared samples different instrumental techniques, such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy, and scanning electron microscopy (SEM) were adopted. For the catalytic evaluation of CMC/LDH/Au, it was utilized as a catalyst in 4-NP and 4-NA reduction reactions. The continuity of the reaction was monitored by a UV–visible spectrophotometer. Rate constant (k app) of 0.48474 min−1 and 0.7486 min−1 were obtained for 4-NP and 4-NA reduction, respectively. The hydrogel beads were recycled and reused for up to five successive cycles without significantly changing their catalytic efficiency. [ABSTRACT FROM AUTHOR]

Abstract: Polybenzimidazole hybrid membranes (H1–H3) were prepared by incorporating different amounts (wt.%) of inorganic hetero poly acids (IHA-Si) into polybenzimidazole (PBI) matrix. Structural, morphological and thermal characteristics of all the hybrid membranes were studied by FT-IR, XRD, SEM and TGA and further investigated functional relationships between the materials structure and metal ion uptake using Hg(II), Pb(II), Y(III), and Cd(II). It was found that H3 was most selective toward Hg(II) as compared to H1 and H2 and further uptake capacity of H1–H3 was strongly dependent on mesoporous silica. The hybrid membranes with high mesoporous silica (H3) exhibited high thermal stability and high uptake capacity toward Hg(II) which was experimentally determined to be 2.48mgg−1. Desorption study for the regeneration of adsorbent was also achieved using ethylenediaminetetraacetic acid solution. Ultimately, the proposed method provided reasonable results for the determination of Hg(II) in environmental water samples. [Copyright &y& Elsevier]

Comparative photocatalytic degradation of polythene films was investigated with undoped and metal (Fe, Ag, and Fe/Ag mix) doped TiO2 nanoparticles under three different conditions such as UV radiation, artificial light, and darkness. Prepared photocatalysts were characterized by XRD, SEM, and EDS techniques. Photocatalytic degradation of the polythene films was determined by monitoring their weight reduction, SEM analysis, and FTIR spectroscopy. Weight of PE films steadily decreased and led to maximum of 14.34% reduction under UV irradiation with Fe/Ag mix doped TiO2 nanoparticles and maximum of 14.28% reduction under artificial light with Ag doped TiO2 nanoparticles in 300 hrs. No weight reduction was observed under darkness. Results reveal that polythene-TiO2 compositing with metal doping has the potential to degrade the polythene waste under irradiation without any pollution. [ABSTRACT FROM AUTHOR]