Electrospun network based on polyacrylonitrile-polyphenyl/titanium oxide nanofibers for high-performance supercapacitor device.

Nanofibers and mat-like polyacrylonitrile-polyphenyl/titanium oxide (PAN-Pph./TiO2) with proper electrochemical properties were fabricated via a single-step electrospinning technique for supercapacitor application. Scanning electron microscopy (SEM), scanning transmission electron microscopy (STEM), thermogravimetry (TGA), fourier transform infrared (FTIR), X-ray diffraction (XRD) and energy dispersive X-ray (EDX) were conducted to characterize the morphological and chemical composition of all fabricated nanofibers. Furthermore, the electrochemical activity of the fabricated nanofibers for energy storage applications (supercapacitor) was probed by cyclic voltammetry (CV), charge-discharge (CD), and electrochemical impedance spectroscopy (EIS). The PAN-PPh./TiO2 nanofiber electrode revealed a proper specific capacitance of 484 F g-1 at a current density of 11.0 A g-1 compared with PAN (198 F g-1), and PAN-PPh. (352 F g-1) nanofibers using the charge-discharge technique. Furthermore, the PAN-PPh./TiO2 nanofiber electrode displayed a proper energy density of 16.8 Wh kg-1 at a power density (P) of 2749.1 Wkg-1. Moreover, the PAN-PPh./TiO2 nanofiber electrode has a low electrical resistance of 23.72 Ω, and outstanding cycling stability of 79.38% capacitance retention after 3000 cycles.

Adsorptive stripping voltammetric sensor based on Cd zeolitic imidazole framework-67 for electrochemical detection of sarin simulant.

A selective and reliable modified glassy carbon sensor, based on a 1.0% Cd zeolitic imidazole framework-67 modified glassy carbon sensor (GCS2), has been developed for ultrasensitive detection of dimethyl methyl phosphonate (DMMP) in human biological fluid. The synthesis of porous nanoparticles of Cd zeolitic imidazole framework-67 (Cd ZIF-67) was carried out via the hydrothermal method. The resulting Cd ZIF-67 powder emerges with good crystallinity, a rhombic dodecahedral morphology with particle size in the range 300 ~ 500 nm, and a specific surface area of 1780 m2·g-1. Furthermore, the fabricated sensor exhibited superior performance in the detection of DMMP with two linearity ranges of 0.02-2.0 nM and 2.0-9.0 nM and a limit of detection (LOD) of 0.06 pM. The fabricated sensor exhibited good reliability, long-term stability, and repeatability, which are favourable attributes for electroanalytical detection. In addition, the fabricated sensor displayed superior performance without significant interference during the assay of DMMP in a biological fluid (human serum sample) within two linearity ranges of 0.1-1.0 nM and 1.0-6.0 nM and a LOD of 0.03 nM.

Dopamine / Artesunate loaded polyhydroxybutyrate-g-cellulose- magnetite zinc oxide core shell nanocomposites: Synergistic antimicrobial and anticancer efficacy.

In this study, polyhydroxybutyrate-g-cellulose - Fe3O4/ZnO (PHB-g-cell- Fe3O4/ZnO) nanocomposites (NCs) was synthesized and used as a delivery system for Dopamine (DO) /Artesunate (ART) drugs. Different types of cells (Ccell, Scell, Pcell) grafted with PHB were designed and mixed with different contents of Fe3O4/ZnO. Physical and chemical features of PHB-g-cell-Fe3O4/ZnO NCs were detected by FTIR, XRD, dynamic light scattering, transmission electron microscopy, and scanning electron microscopy. ART/DO drugs were loaded into PHB-g-cell- Fe3O4/ZnO NCs by single emulsion technique. The rate of drugs release was studied at different pHs (5.4, 7.4). Owing to the overlap between the absorption bands of both drugs, differential pulse adsorptive cathodic stripping voltammetry (DP-AdCSV) was used for the estimation of ART. To study the mechanism of ART and DO release, zero-order, first order, Hixon Crowell, Higuchi and Korsmeyer-Peppas models were applied to the experiment results. The results showed that Ic50 of ART @PHB-g-Ccell-10% DO@ Fe3O4/ZnO, ART @PHB-g-Pcell-10% DO@ Fe3O4/ZnO and ART @PHB-g-Scell-10% DO@ Fe3O4/ZnO were 21.22, 12.3, and 18.11 µg/mL, respectively. The results revealed that ART @PHB-g-Pcell-10% DO@ Fe3O4/ZnO was more effective against HCT-116 than the carriers loaded by a single drug. The antimicrobial efficacy of the nano-loaded drugs was considerably improved compared with free drugs.

Electrochemical stripping voltammetrical sensor based on polypyrrole exfoliated polyetheramine-montmorillonite nanocomposite for nanomolar detection of nifuroxazide.

A series of polypyrrole/polyetheramine-montmorillonite nanocomposites have been fabricated by the intercalation of different types of polyoxyalkylene amine hydrochloride (Jeffamines: D400, D2000, T5000, and T403) into montmorillonite layers via the cation-exchange process followed by in situ polymerization of pyrrole. The physicochemical characteristics of as-prepared nanocomposites were investigated using Fourier transform infrared (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET), and electrochemical impedance spectroscopy (EIS) instruments. The change of the types of Jeffamine causes a change in the geometrical structure, and surface area of nanocomposites. Noteworthy, the resulting polypyrrole/D2000-montmorillonite ([PDM-50]) nanocomposite exhibited a cauliflower-like shape with a specific surface area (116.2 m2 g-1) with the highest conductivity. Furthermore, the modified stripping voltammetric carbon paste sensor was fabricated based on 1.0% [PDM-50] nanocomposites to detect the drug nifuroxazide (NF). The sensor achieved detection limits (LD) of 0.24, and 0.9 nM of NF in the medication, and human urine fluid, respectively. This sensor showed appropriate repeatability, reproducibility, stability, and selectivity for NF sensing in different fluids accompanied by other interferents.

Synthesis and validation of ultrasensitive stripping voltammetric sensor based on polypyrrole@ZnO/Fe3O4 core-shell nanostructure for picomolar detection of artesunate and dopamine drugs.

A stripping voltammetric sensor for ultrasensitive detection of artesunate (ART) and dopamine HCl (DA) has been successfully developed using a Ppy@ZnO/Fe3O4 core-shell nanocomposite ([PZM])-modified carbon paste sensor (MCPS). Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, dynamic light scattering, Brunauer-Emmett-Teller surface area method, and high-resolution transmission electron microscopy were used to characterize the physicochemical properties of the nanomaterials. Noteworthily, the morphology of [PZM] reveals a spherical core-shell nanostructure with an increase in the average diameter range of 20-37.5 nm (specific surface area (SSA) of 28.5 m2 g-1 (0.0247 cm3 g-1)) when compared with the average diameter range 7.5-15.7 nm (SSA of 5.43 m2 g-1 (0.0111 cm3 g-1)) of ZnO/Fe3O4[ZM]. The [PZM] MCPS provided the best electroactive surface area (0.078 cm2) and the least electrocatalytic activity (Rst = 370 Ω). Furthermore, the MCPS showed low detection limits (LODs) of 0.092 pg mL-1 (0.24 pM) and 0.0046 pg mL-1 (0.03 pM) for ART and DA, respectively. Moreover, LODs were found to be 0.029 pg mL-1 (0.75 pM) and 0.014 pg mL-1 (0.09 pM) for ART mixed with 0.7 pM of DA (ART1) and DA in the presence of 2.0 pM of ART drug (DA1), respectively. In addition, the MCPS revealed a proper repeatability, reproducibility, and storage stability (93.5-90.48%). During the routine analysis, the [PZM] MCPS detected ART and DA concentrations in human urine, without interference.

Vanillin-crosslinked chitosan/ZnO nanocomposites as a drug delivery system for 5-fluorouracil: study on the release behavior via mesoporous ZrO2-Co3O4 nanoparticles modified sensor and antitumor activity.

Herein, a series of vanillin-crosslinked chitosan (Vn-CS) nanocomposites (NCs) containing various contents of ZnO nanoparticles (NPs) was prepared and characterized via FTIR spectroscopy, XRD, TGA, SEM and TEM. Changing the weight% of ZnO NPs in the prepared NCs resulted in an improvement in their antibacterial activity against Gram-negative and Gram-positive bacteria strains compared with the unmodified CS, and the encapsulation efficiency of 5-fluorouracil (5-FU) was found to be in the range of 61.4-69.2%. Subsequently, the release of 5-FU was monitored utilizing the mesoporous ZrO2-Co3O4 NPs modified carbon paste sensor via the square-wave adsorptive anodic stripping voltammetry (SW-AdASV) technique. Also, the release mechanism of 5-FU from each NC was studied by applying the zero-order, first-order, Hixson-Crowell and Higuchi models to the experimental results. The cytotoxicity of prepared NCs and 5-FU-encapsulated NCs was evaluated against the HePG-2, MCF-7 and HCT-116 cancer cell lines, in addition to the WI-38 and WISH normal cell lines using the MTT assay. Notably, 5-FU/CV10 NC exhibited the highest antitumor activity towards all tested cancer cell lines and a moderate activity against WI-38 and WISH normal cell lines with IC50 values of 28.02 ± 2.5 and 31.65 ± 2.7 µg mL-1, respectively. The obtained nanocomposites exhibited suitable selectivity with minimum toxicity against normal cells.

Advances of the highly efficient and stable visible light active photocatalyst Zr(IV)-phthalate coordination polymer for the degradation of organic contaminants in water.

This work presents the restoration of the Zr-phthalate coordination polymer (Zr-Ph CP) via valuable application in photocatalysis. Zr-Ph CP was facilely synthesized using a soft hydrothermal method at 70 °C, and was characterized utilizing FTIR, Raman Spectrosopy, XPS, PXRD, SEM/EDX, BET, and a hyperspectral camera. Assessment of its photocatalytic degradation potential was performed against two different dyes, the cationic methylene blue (MB) and the anionic methyl orange (MO), as frequent models of organic contaminants, under properly selected mild visible illumination (9 W) where the bandgap energy (Eg) was determined to be 2.72 eV. Effects of different initial pH values and different dyes' initial concentrations were covered. Photocatalytic degradation studies showed that Zr-Ph CP effectively degraded both dyes for initial pH 7 within about 40-60 minutes. Degradation rate constants were calculated as 0.17 and 0.13 min-1 for MB and MO, respectively. Generally, both direct and indirect mechanisms share in the degradation, where adsorption has shown an important role. The repeated use of Zr-Ph CP does not significantly affect its photocatalytic performance suggesting high water stability.

Green fabrication of 3D hierarchical blossom-like hybrid of peeled montmorillonite-ZnO for in-vitro electrochemical sensing of diltiazem hydrochloride drug.

Herein, a 3D hierarchical blossom-like of Montmorillonite-ZnO (MMt/ZnO) micro-hybrids modified sensors have been successfully fabricated as an extraordinarily electrochemical sensor for detecting of the Diltiazem hydrochloride (DZM.HCl). The 3D hierarchical blossom-like of ZnO and series of MMt/ZnO hybrids have been synthesized using different contents of MMt [FMZ1-5] via a hydrogel polymer template method using alginate ions. The effect of incorporation of different contents of MMt on the morphology, surface area of hybrids were investigated using Fourier transform infrared (FTIR), X-ray diffraction (XRD), Field emission scanning electron microscopy (FE-SEM), Energy-dispersive X-ray spectroscopy (EDS), Brunauer-Emmett-Teller (BET) surface area method, and High-resolution transmission electron microscopy (HR-TEM). The obtained hybrid [FMZ3] with 2.0% of MMt presented the most perfect blossom-like morphology and the highest surface area (190.06 m2/g) with the lowest resistivity. The hierarchical structure of [FMZ3] reveals nanospheres of ZnO with an average diameter of 5.49 nm, which are assembled into nanorods followed by assembling to form a blossom-like shape with the inclusion of MMt peeled layers inside the rod with d-spacing ranges from 1.1-7.4 nm. Meanwhile, the implemented modified sensor 1.0% [FMZ3] CPS retained excellent conductivity and electrocatalytic activity as appraised from the cyclic voltammetry (CV) measurements. Consequently, the electrochemical behavior and the oxidation mechanism of DZM.HCl drug has been investigated at the surface of the constructed sensor. Under the optimum operational conditions, the proposed sensor was successfully achieved detection limits 0.177, and 0.21 nmol·L-1 of DZM.HCl in a commercial and human biological fluid (Serum samples), respectively. The constructed sensor accomplished an appropriate accuracy and free of obstruction from other ordinarily drug excipients.

Fabrication of biosensor based on Chitosan-ZnO/Polypyrrole nanocomposite modified carbon paste electrode for electroanalytical application.

A sensitive conductive nanocomposite sensor consisting of chitosan, zinc oxide nanoparticles, and polypyrrole was developed. The sensor was prepared by oxidative polymerization of pyrrole using (NH4)2S2O8 as the oxidant followed by mixing a Chitosan-Zinc oxide composite with a different content of Chitosan. The morphology and surface area of the nanocomposites were changed by changing the percentage of chitosan. The newly developed nanocomposites also showed a significant improvement in electrical conductivity as mentioned from the cyclic voltammetry measurements of the K3[Fe(CN)6] sample. A square-wave adsorptive anodic stripping voltammetry method successfully measured Isoxsuprine hydrochloride using different types of nanocomposite modified CPEs and showed a large enhancement of stripping peak current compared to bare CPE. Consequently, the proposed sensors proved to have a promissing feature for applications in biosensors.