The Influence of Zinc Oxide with Carbon Nanotube Composite NanoMaterials on Antibacterial Activity

A novel hybrid substance, ZnO: MWCNT, are fabricated from prepared pellets using a pulsed laser ablation liquid technique at varied MWCNT concentrations (0, 3, 5, 10, and 15) wt%. The study cast at the effect of MWCNT concentration on the structure of prepared samples using FTIR and tested for different types of antimicrobial activity. From FTIR examination, one can observe that all the prepared ZnO: MWCNT samples with different concentrations have different types of band (stretching and bending). All the prepared composite samples with various concentrations have showed influence on different types of bacterial, however in general the annealing ZnO, MWCNT and the composite nanomaterial with 15%MWCNT have higher zone of antibacterial activity for studying types of bacterial inhibition.

Influence of blenching agents on the mechanical properties and colour of dental restorative nanocomposite

Purpose: Bleaching agents are commonly used to make the natural dentition look more attractive. Currently, in addition to products from reputable manufacturers, products of not fully known origin are available for purchase. The aim of the study was to investigate whether products of this type have a destructive influence on the mechanical and aesthetic properties of the dental restorative nanocomposite. Design/methodology/approach: Four bleaching agents were used, two recognized brands, and two products were purchased from Chinese websites (their manufacturer is unknown). Two gels and two types of whitening strips were used. One composite nanomaterial was used. Microhardness, diametral tensile strength,, compressive strength and colour measurements were tested. Findings: For some bleaching agents, studies have shown a relatively small effect on mechanical properties and an acceptable effect on colour changes. Regardless of the observed changes, the use of bleaching agents qualified for the experiment should be considered safe for composites. Research limitations/implications: The number of blenching agents used as well as dental composites in this study was limited. In future studies, increasing the number of cycles in the bleaching process should be considered. Practical implications: A popular method of improving the aesthetic properties of teeth is the use of a wide range of blenching agents. Most patients who use teeth whitening procedures are also users of composite fillings. The use of bleaching agents may have a different effect on the mechanical and aesthetic restorative composites. For economic reasons, many people decide to import cheap bleaching agents of unknown or dubious origin via Internet services to perform the bleaching process on their own. In this study, it was investigated whether products of this type have an influence on the mechanical and aesthetic properties of the dental restorative nanocomposite. Originality/value: Until now, no comparison of the safety of the use of bleaching agents of recognized manufacturers and of unknown origin in terms of the effect on composite materials has been presented, despite their high social importance.

Label Free Glucose Electrochemical Biosensor Based on Poly(3,4-ethylenedioxy thiophene):Polystyrene Sulfonate/Titanium Carbide/Graphene Quantum Dots

The electrochemical biosensor devices based on enzymes for monitoring biochemical substances are still considered attractive. We investigated the immobilization of glucose oxidase (GOx) on a new composite nanomaterial poly(3,4-ethylenedioxythiophene): polystyrene sulfonate (PEDOT:PSS)/titanium carbide,(Ti3C2)/graphene quantum dots(GQD) modified screen-printed carbon electrode (SPCE) for glucose sensing. The characterization and electrochemical behavior of PEDOT:PSS/Ti3C2/GQD towards the electrocatalytic oxidation of GOx was analyzed by FTIR, XPS, SEM, cyclic voltammetry (CV), and differential pulse voltammetry (DPV). This composite nanomaterial was found to tend to increase the electrochemical behavior and led to a higher peak current of 100.17 µA compared to 82.01 µA and 95.04 µA for PEDOT:PSS and PEDOT:PSS/Ti3C2 alone. Moreover, the detection results demonstrated that the fabricated biosensor had a linear voltammetry response in the glucose concentration range 0–500µM with a relatively sensitivity of 21.64 µAmM−1cm−2 and a detection limit of 65 µM (S/N = 3), with good stability and selectivity. This finding could be useful as applicable guidance for the modification screen printed carbon (SPCE) electrodes focused on composite PEDOT:PSS/Ti3C2/GQD for efficient detection using an enzyme-based biosensor.

Investigation of Magnetic Properties of Magnetic Poly (glycidyl methacrylate) Microspheres: Experimental and Theoretical

Biocompatible magnetic poly (glycidyl methacrylate) microsphere is a novel nanocomposite with a myriad of promising bioapplications. Investigation of their characteristics by experimental analysis methods has also been carried out in the past. However, a survey of the magnetic anisotropy constant has not been mentioned and the influence of the poly (glycidyl methacrylate) polymer matrix on the Fe3O4 magnetite nanoparticles embedded inside has also not been discussed. Moreover, the accurate characterization of the magnetite nanoparticle size distribution remains challenging. In this paper, we present an effective approach was used to solve these problems. First of all, we combine both experiment and theory to estimate the effective magnetic anisotropy constant. Besides that, we implement an accurate method to determine magnetite nanoparticle size distribution in the magnetic poly (glycidyl methacrylate) microspheres composite nanomaterial.

Electrosynthesis and Characterization of Novel CNx-HMMT Supported Pd Nanocomposite Material for Methanol Electro-Oxidation

In the current research work, palladium (Pd) nanoparticles were electrochemically deposited on a nitrogen doped montmorillonite (CNx-MMT) support using the underpotential deposition (UPD) method. The prepared Pd based composite electrode was studied as an electrocatalyst for methanol fuel oxidation. The catalysts and the supporting materials montmorillonite, acid activated montmorillonite, and nitrogen doped montmorillonite (MMT, HMMT and CNx-HMMT) were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDS) and electrochemical characterization by cyclic voltammetry (CV). The results indicated that Pd supported on CNx-HMMT possesses enhanced electrocatalytic activity and stability compared to commercial Pd/C, which was attributed to its higher electrochemical surface area (ECSA) (23.00 m2 g−1). The results demonstrated the potential application of novel Pd/CNx-HMMT composite nanomaterial as electrocatalysts for methanol electrooxidation in direct methanol fuel cells (DMFCs).

Technology of obtaining nanocomposites for sorption purification of aqueous media

The paper presents a technique for obtaining a universal composite nanomaterial for effective sorption water purification from pollutants of various chemical nature. The proposed material is a nanocomposite based on reduced graphene oxide modified with a functional organic component — polyaniline, which also includes oxidized carbon nanotubes as a structure former. The use of polyaniline makes it possible to significantly increase the activity and sorption capacity of the developed graphene material. The authors were developed a number of nanocomposites, which differ in the final stage of the pre-prepared hydrogel technology: drying in air (drying oven), freeze drying, drying under supercritical conditions (supercritical fluid — isopropyl alcohol). In addition, the effect of carbonization as an additional stage (T = 800 °C, argon) was studied in the article. The materials surface morphology was evaluated using scanning electron microscopy. The specific surface area and the parameters of the porous space were determined by nitrogen adsorption. The materials specific surface area increases depending on the choice of drying technology for the initial hydrogel (drying oven — 80 m2/g → freeze drying — 180 m2/g → supercritical drying — 290 m2/g), and also increases after the carbonization stage and reaches a value of ~ 350 m2/g. The nanocomposites sorption capacity to the organic dyes (methylene blue (MB) and solar yellow (SY)), as well as to heavy metals (for example, zinc ions) was determined. It was found that the value of MB sorption is up 1380 to 1800 mg/g, for SY — up 159 to 300 mg/g, for zinc — up 31 to 230 mg/g. At the same time, the sample processed under supercritical conditions, followed by carbonization, were shown the best characteristics.