This article attempt to synthesis titanium dioxide (TiO2) doped zinc oxide (ZnO) composite via Pulsed Laser Ablation in Liquids (PLAL) and study its antibacterial properties. The structure, optical, ...morphological of the prepared composite have been investigated via various technique. FT-IR results confirm existence of TiO2 doped ZnO. XRD measurements approved the enhanced crystallinity ZnO after doped by TiO2 via PLAL technique. The optical transmittance was enhanced from 78.6% of pure ZnO to 92.3% for TiO2 doped ZnO. TEM images of ZnO showed an obvious elongated rod-like shapes that were rectangular or hexagonal and spherical particles. Moreover, the cell viability has been studied for the papered pure ZnO and TiO2 doped ZnO. The minimum cell viability ratio was about 81.4 ± 4.2% for pure ZnO and was increased to 91.6 ± 5.1% for TiO2 doped ZnO. The antibacterial activity of the samples that measured via MIZ approved that the TiO2 doped ZnO make a raise in the activity index. It was suggested that TiO2 doped ZnO can be used in many antimicrobial application.
Nanocomposite thin film of silver/copper oxide has been performed by pulsed laser deposition (PLD) route. Second harmonic generation nanosecond laser (532 nm) has been utilized as laser source for ...PLD technique. This Ag/CuO nanocomposite thin film obtained as catalytic sheet used in reduction of nitrophenol. The properties of the synthesized Ag/CuO thin film were illustrated via different routes. XRD results obtained the crystallinity of the synthesized both CuO thin film and Ag/CuO nanocomposite thin film. UV–visible spectra showed enhancing in the transmittance values of Ag/CuO nanocomposite thin film comparing to the sample of CuO thin film. The value of direct energy band gap for CuO thin film was 2.51 eV that reduced to 2.15 eV in Ag/CuO nanocomposite thin film. FE-SEM photos showed a spherical shape of copper oxide nanoparticles with some dispersed spherical silver nanoparticles. The catalytic activity of 4-NP reduction for Ag/CuO nanocomposite thin film reducing the time of the reduction from 90 min to 30 min.
•Ag/CuO nanocomposite thin film was synthesized via PLD technique.•4-NP was completely converted to 4-AP by Ag/CuO nanocomposite thin film in 30 min.•Ag/CuO nanocomposite thin film shows enhanced degradation efficiency than CuO thin film.
A large fraction of population is suffering from waterborne diseases due to the contaminated drinking water. Both anthropogenic and natural sources are responsible for water contamination. Revolution ...in industrial and agriculture sectors along with a huge increase in human population has brought more amount of wastes like heavy metals, pesticides and antibiotics. These toxins are very harmful for human health, therefore, it is necessary to sense their presence in environment. Conventional strategies face various problems in detection and quantification of these pollutants such as expensive equipment and requirement of high maintenance with limited portability. Recently, nanostructured devices have been developed to detect environmental pollutants. Polymeric nanocomposites have been found robust, cost effective, highly efficient and accurate for sensing various environmental pollutants and this is due to their porous framework, multi-functionalities, redox properties, great conductivity, catalytic features, facile operation at room temperature and large surface area. Synergistic effects between polymeric matrix and nanomaterials are responsible for improved sensing features and environmental adaptability. This review focuses on the recent advancement in polymeric nanocomposites for sensing heavy metals, pesticides and antibiotics. The advantages, disadvantages, operating conditions and future perspectives of polymeric nanocomposites for sensing toxic pollutants have also been discussed.
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•Different polymer/inorganic nanocomposites based sensors have been discussed.•Polymer/inorganic nanocomposite as emerging tool for sensing environmental pollutants.•Selectivity, accuracy and stability of nanocomposites based sensors have been reviewed.
All-solid-state potentiometric sensors were prepared by using polyaniline (PANI) as the solid contact material. A film of PANI (thickness approximately being 0.25 µm) was deposited on a solid ...substrate (carbon screen printed platform). The PANI layer was subsequently coated with an ion-selective membrane (ISM) containing uniform-sized molecularly imprinted nanoparticles to produce a solid-contact ion-selective electrode (SC/ISE) for bispyribac herbicide (sensor I). In addition, aliquat 336 was also used as an ion exchanger in plasticized PVC membrane (sensor II). The proposed sensors revealed a remarkably improved sensitivity towards bispyribac ions with anionic slopes of -47.8 ± 1.1 (r² = 0.9995) and -44.4 ± 1.4 (r² = 0.9997) mV/decade over a linear range 1.0 × 10
⁻8.6 × 10
M, 1.0 × 10
⁻9.0 × 10
M and detection limits of 1.33 and 1.81 µg/mL for sensors I and II, respectively.Selectivity of both sensors is significantly high for different common pesticides and inorganic anions. The potential stability of the SC/ISEs was studied using chronopotentiometry. Electrochemical impedance spectrometry was used to understand the charge-transfer mechanisms of the different types of ion-selective electrodes studied. The impedance response of the electrodes was modelled by using equivalent electrical circuits. The sensors were used for a direct measurement of the bispyribac content in commercial herbicide formulations and soil samples collected from agricultural lands planted with rice and sprayed with bispyribac herbicide. The results agree fairly well with data obtained using HPLC method.
Blend of Polyvinyl Alcohol/Chitosan doped by selenium nanoparticles was synthesized via one step laser ablation route to improve the antibacterial activity of the pure blend. The effect of two ...concentrations of selenium on the optical, structural, and morphological properties of the synthesized PVA/Chitosan/SeNPs nanocomposite films were characterized. The antibacterial activity of the prepared samples has been investigated. XRD and FTIR-ATR results confirm the interaction between selenium nanoparticles and PVA/Chitosan. Furthermore, the change in the values of optical energy band gap confirms the scattered selenium nanoparticles into PVA/Chitosan film. The activity index shows an increase in the diameter zone with increasing the concentration of selenium nanoparticles content. The results confirmed that doping of selenium nanoparticles to (PVA/Chitosan) lead to increase the antibacterial activity of the pure PVA/Chitosan blend that suggests this nanocomposite could be used in several antimicrobial applications.
In this study, hybrid analogs of benzimidazole containing a thiazole moiety (1–17) were afforded and then tested for their ability to inhibit α-amylase and α-glucosidase when compared to acarbose as ...a standard drug. The recently available analogs showed a wide variety of inhibitory potentials that ranged between 1.31 ± 0.05 and 38.60 ± 0.70 µM (against α-amylase) and between 2.71 ± 0.10 and 42.31 ± 0.70 µM (against α-glucosidase) under the positive control of acarbose (IC50 = 10.30 ± 0.20 µM against α-amylase) (IC50 = 9.80 ± 0.20 µM against α-glucosidase). A structure–activity relationship (SAR) study was carried out for all analogs based on substitution patterns around both rings B and C respectively. It was concluded from the SAR study that analogs bearing either substituent(s) of smaller size (−F and Cl) or substituent(s) capable of forming hydrogen bonding (−OH) with the catalytic residues of targeted enzymes enhanced the inhibitory potentials. Therefore, analogs 2 (bearing meta-fluoro substitution), 3 (having para-fluoro substitution) and 4 (with ortho-fluoro group) showed enhanced potency when evaluated against standard acarbose drug with IC50 values of 4.10 ± 0.10, 1.30 ± 0.05 and 1.90 ± 0.10 (against α-amylase) and 5.60 ± 0.10, 2.70 ± 0.10 and 2.90 ± 0.10 µM (against α-glucosidase), correspondingly. On the other hand, analogs bearing substituent(s) of either a bulky nature (−Br) or that are incapable of forming hydrogen bonds (−CH3) were found to lower the inhibitory potentials. In order to investigate the binding sites for synthetic analogs and how they interact with the active areas of both targeted enzymes, molecular docking studies were also conducted on the potent analogs. The results showed that these analogs adopted many important interactions with the active areas of enzymes. The precise structure of the newly synthesized compounds was confirmed using several spectroscopic techniques as NMR and HREI-MS.
Targeted delivery of drug molecules to diseased sites is a great challenge in pharmaceutical and biomedical sciences. Fabrication of drug delivery systems (DDS) to target and/or diagnose sick cells ...is an effective means to achieve good therapeutic results along with a minimal toxicological impact on healthy cells. Biopolymers are becoming an important class of materials owing to their biodegradability, good compatibility, non-toxicity, non-immunogenicity, and long blood circulation time and high drug loading ratio for both macros as well as micro-sized drug molecules. This review summarizes the recent trends in biopolymer-based DDS, forecasting their broad future clinical applications. Cellulose chitosan, starch, silk fibroins, collagen, albumin, gelatin, alginate, agar, proteins and peptides have shown potential applications in DDS. A range of synthetic techniques have been reported to design the DDS and are discussed in the current study which is being successfully employed in ocular, dental, transdermal and intranasal delivery systems. Different formulations of DDS are also overviewed in this review article along with synthesis techniques employed for designing the DDS. The possibility of these biopolymer applications points to a new route for creating unique DDS with enhanced therapeutic qualities for scaling up creative formulations up to the clinical level.
Our findings revealed that the composition of the constituents, reaction conditions, and synthetic processes all influence the characteristics and therefore the applications of the resulting biopolymer composites.
Diabetes mellitus (DM) is a rapidly prevailing disease throughout the world that poses boundless risk factors linked to several health problems. Vildagliptin is the standard dipeptidyl peptidase-4 ...(DPP-4) inhibitor type of medication that is used for the treatment of diabetes anti-hyperglycemic agent (anti-diabetic drug). The current study aimed to synthesize vildagliptin-loaded ZnO NPs for enhanced efficacy in terms of increased retention time minimizing side effects and increased hypoglycemic effects. Herein, Zinc Oxide (ZnO) nanoparticles (NPs) were constructed by precipitation method then the drug vildagliptin was loaded and drug loading efficiency was estimated by the HPLC method. X-ray diffraction analysis (XRD), UV–vis spectroscopy, FT-IR, scanning electron microscope (SEM), and EDX analysis were performed for the characterization of synthesized vildagliptin-loaded ZnO NPs. The UV–visible spectrum shows a distinct peak at 363 nm which confirms the creation of ZnO NPs and SEM showed mono-dispersed sphere-shaped NPs. EDX analysis shows the presence of desired elements along with the elemental composition. The physio-sorption studies, which used adsorption isotherms to assess adsorption capabilities, found that the Freundlich isotherm model explains the data very well and fits best. The maximum adsorption efficiency of 58.83% was obtained. Further, In vitro, anti-diabetic activity was evaluated by determining the α-amylase and DPP IV inhibition activity of the product formed. The formulation gave maximum inhibition of 82.06% and 94.73% of α-amylase and DPP IV respectively. While at 1000 µg/ml concentration with IC50 values of 24.11 μg/per ml and 42.94 μg/ml. The inhibition of α-amylase can be ascribed to the interactive effect of ZnO NPs and vildagliptin.
Pure and Al, Fe doped/co-doped zinc oxide (ZnO) thin films were prepared using spray pyrolysis technique with optimised deposition parameters. Micro-structural properties of the films were carried ...out using X-ray diffraction (XRD), transmission electron microscopy (TEM) and Raman spectroscopy. XRD results have shown that the deposited thin films were polycrystalline in nature with Wurtize structure. Crystallite size was determined and it was found to be decreased with single dopants and increased while co-doping in the zinc oxide matrix. Morphological studies have been studied by using Atomic Force Microscopy and Field Emission Scanning Electron Microscopy. They have clearly shown that the deposited thin films are agglomerated spherical particles with uniform distribution. Optical properties of the films were measured by UV–Vis spectrophotometer. Optical band gap was determined using Touc plot. Gas sensing characterization of pure and doped/co-doped ZnO thin films were carried out at room temperature in static liquid distribution method towards different gases such as acetone, ethanol, xylene and ammonia. Response and recovery times were also calculated and reported.
In the current article di-aldehyde alginate (DAA) crosslinking gelatin (Ge) hydrogel was prepared and investigated for stabilizing silver nanoparticles. DAA/Ge decorated silver nanoparticles hydrogel ...was characterized by IR, XRD, TGA, SEM and AFM. The outcomes demonstrate that silver nanoparticles with uniform sizes were homogenously distributed through DAA/Ge hydrogel. DAA/Ge decorated silver nanocomposite was examined for the rejection of methylene blue (MB) from aqueous solutions. Comparing with DAA/Ge hydrogel, the nanocomposite has high efficiency for removal of MB. The highest MB removal efficiency was observed at pH 7 and the adsorption process is well described by pseudo-second order and Langmuir adsorption model with adsorption capacity of 625 mg/g. Our results proved that the DAA/Ge/Ag nanocomposite could be used for removal of MB from decontaminated solutions.
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