Application of Electrochemical Techniques for Determining and Extracting Natural Product (EgCg) by the Synthesized Conductive Polymer Electrode (Ppy/Pan/rGO) Impregnated with Nano-Particles of TiO2.

The polypyrrole/polyaniline-based electrode (Ppy/Pan/TiO2/rGO) was fabricated via the electrophoretic deposition technique on fluorine-doped tin oxide (FTO)-coated glass. Physico-electrochemical adsorption/desorption of epigallocatechin gallate (EgCg) as an electroactive species was enhanced by the fabricated electrode compared to the electroless technique extraction using the same electrode. EgCg was electrochemically extracted using chronoamperometry by electrophoretically deposited Ppy/Pan/TiO2/rGO film. Isolated EgCg was qualified and quantified by the voltammetry and high-performance liquid chromatography (HPLC) techniques. It was found that the extracted EgCg values were 3.38 and 0.72 ppm from a 10 ppm prepared solution using the electrochemically and physically based techniques, respectively. Morphology/elemental analysis and crystal structure of the prepared electrodes were characterized by field emission scanning electron microscopy/energy-dispersive X-ray (FESEM/EDX) and X-ray diffraction (XRD), respectively. The conductivity of the fabricated electrode was investigated by electrochemical impedance spectroscopy (EIS) and was calculated as 1.124 S/cm for the electrophoretically deposited electrodes (EPD).

Bio-Based Adhesives and Evaluation for Wood Composites Application.

There has been a rapid growth in research and innovation of bio-based adhesives in the engineered wood product industry. This article reviews the recent research published over the last few decades on the synthesis of bio-adhesives derived from such renewable resources as lignin, starch, and plant proteins. The chemical structure of these biopolymers is described and discussed to highlight the active functional groups that are used in the synthesis of bio-adhesives. The potentials and drawbacks of each biomass are then discussed in detail; some methods have been suggested to modify their chemical structures and to improve their properties including water resistance and bonding strength for their ultimate application as wood adhesives. Moreover, this article includes discussion of techniques commonly used for evaluating the petroleum-based wood adhesives in terms of mechanical properties and penetration behavior, which are expected to be more widely applied to bio-based wood adhesives to better evaluate their prospect for wood composites application.