Nowadays the development of sustainable technologies for the effective production of polymeric materials that can be used as biomaterials will be of importance. In this work, cellulose (CEL) was purified from potato peel waste (PPW) and used to produce electrospun nanofibers for tissue engineering applications. The purified CEL was solubilized in copper ethylenediamine (Cuen) and the electrospun nanofibers was produced through electrospinning technique in diameter range of 250–500 nm at electrical field strength of 20 kV. To confirm the applicability of the electrospun CEL scaffolds in tissue engineering, in vitro BALB-3T3 fibroblastic cell adhesion and cell proliferation tests were employed in this study. Cell viability was evaluated by staining with ethidium bromide (EtBr) and acridine orange (AO) to evaluate the possible effects of cytotoxicity of the CNF scaffolds. Fluorescence studies confirmed that BALB-3T3 viable cells attached and spread throughout the CEL scaffold. The attachment and spreading of viable cells suggests that electrospun CEL scaffolds support growth of BALB-3T3 fibroblasts cells and suggests that PPW can be a useful source of raw material for the production of scaffolds for tissue engineering.

This study presents a new methodology for graphene oxide (GO) synthesis through electrochemical exfoliation of graphite, followed by phthalic anhydride functionalization (PhA-GO) and doping with Cu${}^{2+}$ and Ag${}^{+}$ ions. The synthesis of GO involved the use of an electrochemical cell with H${}_2$SO${}_4$ as the electrolyte, with a gradual increase in potential from 2.3 V to 10 V. Extensive characterization techniques confirmed the successful incorporation of oxygen-containing functional groups, verifying the oxidation of graphite. PhA-GO functionalization was confirmed by thermogravimetric analysis, Differential Scanning Calorimetry, Fourier-transform infrared spectroscopy (FTIR), UV-Vis spectroscopy, X-ray diffraction, scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDX), which confirmed the presence of Cu${}^{2+}$ and Ag${}^{+}$ ions. The Scherrer equation determined a grain size of 75.85 nm for GO. The electrical properties exhibited semiconductor and semimetal behavior, particularly in PhA-GO/Ag${}^{+}$ composites, making them suitable for electronic devices over a wide temperature range, presenting a promising pathway for advanced materials in electronic applications.

A platinum electrode (Pt) was coated with poly(2-hydroxyethyl methacrylate) (PHEMA) by electrochemical polymerization using chronopotentiometry. Electropolymerization of polyaniline nanowires doped with camphorsulfonic acid (PANI:CSA) was further performed on the surface of the Pt-PHEMA electrode by cyclic voltammetry. The coated Pt-PHEMA-PANI:CSA electrode was characterized by Fourier transform infrared spectroscopy (FTIR), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and scanning electron microscopy (SEM). According to EIS, the Pt-PHEMA electrode exhibits a charge transport resistance (Rct) of 169.19 kΩ. The EIS analysis of Pt-PHEMA-PANI:CSA electrode reveals a less resistive character (Rct=1.28 Ω) than the observed for the Pt electrode coated with PANI:CSA (Rct=0.47 kΩ). As demonstrated by SEM, the Pt-PHEMA-PANI:CSA electrode has a high surface area due to the PANI:CSA nanowires embedded in Pt-PHEMA. The biocompatibility of PHEMA, allied to the electrochemical characteristics of PANI:CSA, could be useful to the development of implantable electrodes for biomedical applications.

Graphene oxide (GO) was electropolymerized with polyaniline (PANI) during graphite exfoliation in 0.1 M H₂SO₄ electrolyte and 0.1 M aniline monomer solution. Characterization techniques, including Infrared Absorption Spectroscopy (FTIR), Thermogravimetric Analysis (TGA), UV-vis spectroscopy, X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), and cyclic voltammetry, were utilized. XRD analysis confirmed GO multilayer exfoliation from the graphite anode, while UV-vis and FTIR techniques confirmed PANI electropolymerization. SEM images revealed PANI distributed between GO multilayers with a nanoneedle morphology. Cyclic voltammetry in 1 M H₂SO₄ demonstrated that the GO/PANI composite achieved a specific capacitance of 117.440 Fg^-1, in contrast to GO's 1.243 Fg^-1, both at a scan rate of 1 mVs^-1. This enhancement is attributed to the improved electrical conductivity from PANI and graphene oxide. These results highlight the potential of the GO/PANI composite for high-performance supercapacitors and energy storage systems.