Surface plasmon resonance detection of copper corrosion in biodiesel using polypyrrole-chitosan layer sensor

Copper corrosion is one of the important parameters used for evaluating the quality of biodiesel. In this work, a polypyrrole-chitosan sensing layer was utilized for the detection of Cu2+ in biodiesel using the surface plasmon resonance technique. With the sensitivity of this sensor being about 0.1 ppm, different corrosion levels could be recognized in samples that were classified as class 1a according to the standard copper strip test

Polypyrrole thin film sensor base surface plasmon resonance for detection of Cu(II) and Fe(III) in aqueous solution

In this study, the performance of surface plasmon resonance method incorporated with polypyrrole sensing layer was examined for detection of Cu (II) and Fe (III) ions in aqueous solutions. The polypyrrole was prepared by electro-oxidation method on a gold layer for the detecting low concentration ions (0.1, 1 5 10 20 ppm). The experiments carried out at room temperature, and each sample was flowed through the flow cell. A photodiode registered the SPR signals as the function of rotation angle and thickness of layers. For observing the association and dissociation processes, the experiments repeated more than ten times, and the sensorgrams were obtained. Furthermore, Langmuir model was utilized to describe the binding interactions of ions with the polypyrrole layer. The lower concentration detection limit was about 0.1 ppm and the terminal resonance angles were occurred after the 300 s. The sensor was also found to be more sensitive to the presence of Cu than Fe ions

Synthesis and application of polypyrrole/carrageenan nano-bio composite as a cathode catalyst in microbial fuel cells

A novel nano-bio composite polypyrrole (PPy)/kappa-carrageenan(KC) was fabricated and characterized for application as a cathode catalyst in a microbial fuel cell (MFC). High resolution SEM and TEM verified the bud-like shape and uniform distribution of the PPy in the KC matrix. X-ray diffraction (XRD) has approved the amorphous structure of the PPy/KC as well. The PPy/KC nano-bio composites were then studied as an electrode material, due to their oxygen reduction reaction (ORR) ability as the cathode catalyst in the MFC and the results were compared with platinum (Pt) as the most common cathode catalyst. The produced power density of the PPy/KC was 72.1 mW/m2 while it was 46.8 mW/m2 and 28.8 mW/m2 for KC and PPy individually. The efficiency of the PPy/KC electrode system is slightly lower than a Pt electrode (79.9 mW/m2) but due to the high cost of Pt electrodes, the PPy/KC electrode system has potential to be an alternative electrode system for MFCs

Conducting polymer composite based on nano-cellulose for biosensing application

Application of conducting polymers of polypyrrole and polyaniline-cellulose nanocrystal based composite as electron-transfer pathways in enzyme electrodes was investigated. Polypyrrole-cellulose nanocrystal (PPy-CNC)-based composite as a novel immobilization membrane was prepared by chemical polymerization. Modified electrodes were prepared based on drop casting of nanocomposite suspension on the screen printed electrode (SPE) surface following by GOx immobilization. Field emission scanning electron microscopy (FESEM) images showed the porous structure of the nanocomposite with large surface area which could accommodate a large quantity of enzyme and allow the rapid diffusion of the active enzyme into the sensing membrane. The electrochemical and DPV responses of the GOx for glucose biosensor detection were examined in detail. The anodic current (Ip) in the voltammogram of the modified electrode prepared from PPy-CNC showed higher value compare to modified electrode prepared from pure polymer indicating CNC enhanced electron transferring and biosensor performance. The modified glucose biosensor exhibits a high sensitivity (ca. 0.73 μA.mM−1), with a dynamic response ranging from 1.0 to 20 mM glucose. The modified glucose biosensor exhibits a limit of detection (LOD) of (50±10) μM and also excludes interfering species, such as ascorbic acid, uric acid, and cholesterol, which makes this sensor suitable for glucose determination in real samples. This sensor displays an acceptable reproducibility and stability over time. The current response was maintained over 95% of the initial value after 17 days, and the current difference measurement obtained using different electrodes provided a relative standard deviation (RSD) of 4.47%

One-step electrochemical deposition of PolypyrroleChitosanIron oxide nanocomposite films for non-enzymatic glucose biosensor

One-step electrodeposition method of Polypyrrole–Chitosan–Iron oxide (Ppy–CS–Fe3O4) nanocomposite films (Ppy–CS–Fe3O4NP/ITO) has been developed for the fabrication of advanced composite coatings for biosensors applications. The FESEM and EDX results provide the evidence of successful incorporation of Fe3O4 into Ppy–CS molecules. The presence of Fe3O4 nanoparticles in the nanocomposite films was further confirmed by the XRD and XPS spectrums. The fabricated electrode Ppy–CS–Fe3O4 NP/ITO shows a fast amperometric response with high selectivity to detect glucose non-enzymatically with improved linearity (1–16 mM) and the detection limit of (234 μM) at a signal-to-noise ratio (S/N=3.0)

Polyaniline-modified nanocellulose prepared from Semantan bamboo by chemical polymerization: preparation and characterization

Crystalline nanocellulose was prepared from Semantan bamboo (Gigantochloa scortechinii) via acid hydrolysis and was used to synthesize a nanocomposite of polyaniline/crystalline nanocellulose (PANi/CNC) via in situ oxidative polymerization of aniline in the presence of crystalline nanocellulose. The electrochemical properties of the nanocomposite were studied using a modified PANi/CNC electrode via cyclic voltammetry, and higher current response was observed for the PANi/CNC-modified electrode compared to that for the modified electrode with PANi. The results obtained from EIS displayed lower value of Rct for the PANi/CNC-modified electrode, indicating that the incorporation of CNC into the PANi structure could enhance the electron transfer rate. The characteristic peaks of PANi and CNC were observed in the FTIR spectra of the nanocomposite, indicating the incorporation of CNC inside the nanocomposite structure. Moreover, in the XRD diffractogram, lower crystallinity was observed at the 2 theta values of 22.6 and 16.1 for PANi/CNC compared to that for pure CNC. The FESEM images showed high porosity of the nanostructure with no phase separation, revealing the homogenous polymerization of the monomer on the surface of the crystalline cellulose. Aggregation of PANi particles was observed with the increasing aniline concentration

Application of polypyrrole-chitosan layer for detection of Zn (II) and Ni (II) in aqueous solutions using surface plasmon resonance

In this study, a polypyrrole-chitosan layer was applied to detect zinc and nickel ions in aqueous solution using surface plasmon resonance. The resonance angle shift was found to monitor the binding interaction between ions and the polymer film. The polypyrrole-chitosan film was coated on the gold layer with an electrochemical deposition method. The Langmuir model was compared with the Freundlich model to explain the binding. Consequently, the Langmuir model was fitted with experimental data better than the Freundlich equation, and the detection limit was 0.01 ppm

Comparative study of the electrochemical, biomedical, and thermal properties of natural and synthetics nanomaterials

In this research, natural nanomaterials including cellulose nanocrystal (CNC), nanofiber cellulose (NFC), and synthetic nanoparticles such as carbon nanofiber (CNF) and carbon nanotube (CNT) with different structures, sizes, and surface areas were produced and analyzed. The most significant contribution of this study is to evaluate and compare these nanomaterials based on the effects of their structures and morphologies on their electrochemical, biomedical, and thermal properties. Based on the obtained results, the natural nanomaterials with low dimension and surface area have zero cytotoxicity effects on the living cells at 12.5 and 3.125 μg/ml concentrations of NFC and CNC, respectively. Meanwhile, synthetic nanomaterials with the high surface area around 15.3–21.1 m2 /g and significant thermal stability (480 °C–600 °C) enhance the output of electrode by creating a higher surface area and decreasing the current flow resistance

Synthesizing methylammonium-octhylammonium lead bromide hybrid perovskite nanoparticles

Organic-Inorganic hybrid perovskite materials have attracted significant research interest in the field of photovoltaic as well as light emitting applications. Methylammonium-Octylammonium Lead Bromide (MOPbBr3) as one of the organic-inorganic hybrid perovskite materials have been synthesized through non template chemical precipitation technique. This technique is simple and allows low cost solution processing in low temperature route to form MOPbBr3 nanoparticles. The formation of MOPbBr3 nanoparticles has been characterized through X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM), X-Ray Fluorences (XRF) analyzer and Nuclear Magnetic Resonance (NMR). Exploiting the optical properties through UV-Vis spectroscopy and photoluminescence spectroscopy specifically could greatly enhance the efficiency and functionality of applications based on this materials