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•AgGO with enhanced absorption in the visible spectrum through a single-step surfactant-free facile method was prepared.•WO3-x/AgrGO composite with better photocatalytic activity was ...prepared by doping WO3-x by AgGO via a hydrothermal process.•Better carrier separation and reduced impedance leading to RhB degradation and bacterial inactivation.•It exhibits versatilities for photocatalytic activities in visible regions.•Stability tests suggest its excellent reusability.
Suppressing charge recombination in semiconductors via triggering interfacial polarization and synergism provides an effective way to redeem multifunctionality and achieve environmental sustainability. Herein, we anchor a single-step facile synthesis of AgGO, providing bandgap control through varying oxidation time and subsequent simultaneous incorporation of Ag and rGO via the in situ hydrothermal method in WO3-x. The resulting WO3-x/AgrGO composite demonstrated a broadening of optical absorption and excellent suppression of carrier recombination, thereby improving the catalytic properties. The synergism and excellent conductivity of AgrGO enhance the interfacial polarization to store the carriers for longer times and help carriers carry most of their energy to the catalyst’s surface. When WO3-x/AgrGO was tested against RhB under visible light irradiation, its degradation constant reached 0.034/min, 7.4 times faster than pure WO3-x. It has left no viable bacteria during the photoinactivation of gram-negative E. coli bacteria, and even its inactivation rate is 1.07 times faster than AgGO. So, this study provides a direct method of metal-GO composite synthesis and subsequent introduction into WO3-x to broaden the versatility of environmental semiconductors.
Different concentrations of zirconium with a fixed quantity (4 wt%) of chitosan (CS) doped nickel cobaltite (NiCo2O4) nanorods were synthesized using a co-precipitation approach. This cutting-edge ...research explores the cooperative effect of Zr-doped CS-NiCo2O4 to degrade the Eriochrome black T (EBT) and investigates potent antibacterial activity against Staphylococcus aureus (S. aureus). Advanced characterization techniques were conducted to analyze structural textures, morphological analysis, and optical characteristics of synthesized materials. XRD pattern unveiled the spinal cubic structure of NiCo2O4, incorporating Zr and CS peak shifted to a lower 2θ value. UV–Vis spectroscopy revealed the absorption range increased with CS and the same trend was observed upon Zr, showing a decrease in bandgap energy (Eg) from 2.55 to 2.4 eV. The optimal photocatalytic efficacy of doped NiCo2O4 within the basic medium was around 96.26 %, and bactericidal efficacy was examined against S. aureus, revealing a remarkable inhibition zone (5.95 mm).
•To synthesis the cerium oxide nanoparticles using different sources.•Biomedical applications of cerium oxide nanoparticles.•Applications of cerium oxide nanoparticles in toxicity studies.
A cerium ...oxide nanoparticles (nanoceria) has a wide range of applications in different fields, especially biomedical division. As a matter of concern, it has a major impact on the human health and environment. The aim of this review is to address the different ways of synthesis of nanoceria using chemical and green synthesis methods and characterization and the applications of nanoceria for antioxidant, anticancer, antibacterial activities and toxicological studies including the most recent studies carried out in vivo and in vitro to study the problems. We have exclusively discussed on the toxicology of nanoceria exposed to the general public along with recent advances in the studies of antimicrobial, toxicity and anti-oxidant activity.
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•The carbon/cerium oxide composites were prepared with the assistance of the glucose-based surfactant and impregnated to Fabrics.•The resultant CeO2–C composites exhibited excellent ...antibacterial activity.•The nanocomposites demonstrate efficient sunlight-driven photocatalytic activity.•The nanocomposites results in a synergistic effect, enhancing both antibacterial and photocatalytic performances.•The developed textiles hold promise for various healthcare applications.
This work inspects the antibacterial activity and sunlight-driven photocatalytic activity effect of nanocomposites of CeO2 and carbon as a surface coating onto the fabric with self-cleaning properties. The nanocomposites of CeO2 and carbon were confirmed by XRD, FTIR, Laser Raman and TEM, revealing the amorphous nature of carbon and the crystallographic structure of CeO2 nanoparticles. TEM depicted a sheet-like structure of carbon and orbicular morphology of CeO2. The nanocomposite was impregnated onto fabrics using an immersion and ultrasonication method. The fabrics impregnated with nanocomposites exposed a clear zone of inhibition of E. Coli and S.aureus bacterial strains, indicating potent bactericidal properties. The nanocomposite-impregnated fabrics show efficient and strong photocatalytic activity against P-Rosaniline Hydrochloride (PRH) dye, which was investigated at different concentrations of dye, repeatability, and reusability with time. The notable photocatalytic activity of the fabrics underscores their potential for use in anti-infection applications.
Tigecycline is unique glycylcycline class of semisynthetic antimicrobial agents developed for the treatment of polymicrobial infections caused by multidrug-resistant Gram-positive and Gram-negative ...pathogens. Tigecycline evades the main tetracycline resistance genetic mechanisms, such as tetracycline-specific efflux pump acquisition and ribosomal protection, via the addition of a glycyclamide moiety to the 9-position of minocycline. The use of the parenteral form of tigecycline is approved for complicated skin and skin structure infections (excluding diabetes foot infection), complicated intra-abdominal infections, and community-acquired bacterial pneumonia in adults. New evidence also suggests the effectiveness of tigecycline for the treatment of severe
Clostridioides difficile
infections. Tigecycline showed in vitro susceptibility to
Coxiella
spp.,
Rickettsia
spp., and multidrug-resistant
Neisseria gonnorrhoeae
strains which indicate the possible use of tigecycline in the treatment of infections caused by these pathogens. Except for intrinsic, or often reported resistance in some Gram-negatives, tigecycline is effective against a wide range of multidrug-resistant nosocomial pathogens. Herein, we summarize the currently available data on tigecycline pharmacokinetics and pharmacodynamics, its mechanism of action, the epidemiology of tigecycline resistance, and its clinical effectiveness.
The cytotoxicity of 2D graphene-based nanomaterials (GBNs) is highly important for engineered applications and environmental health. However, the isotropic orientation of GBNs, most notably graphene ...oxide (GO), in previous experimental studies obscured the interpretation of cytotoxic contributions of nanosheet edges. Here, we investigate the orientation-dependent interaction of GBNs with bacteria using GO composite films. To produce the films, GO nanosheets are aligned in a magnetic field, immobilized by crosslinking of the surrounding matrix, and exposed on the surface through oxidative etching. Characterization by small-angle X-ray scattering and atomic force microscopy confirms that GO nanosheets align progressively well with increasing magnetic field strength and that the alignment is effectively preserved by crosslinking. When contacted with the model bacterium Escherichia coli, GO nanosheets with vertical orientation exhibit enhanced antibacterial activity compared with random and horizontal orientations. Further characterization is performed to explain the enhanced antibacterial activity of the film with vertically aligned GO. Using phospholipid vesicles as a model system, we observe that GO nanosheets induce physical disruption of the lipid bilayer. Additionally, we find substantial GO-induced oxidation of glutathione, a model intracellular antioxidant, paired with limited generation of reactive oxygen species, suggesting that oxidation occurs through a direct electrontransfer mechanism. These physical and chemical mechanisms both require nanosheet penetration of the cell membrane, suggesting that the enhanced antibacterial activity of the film with vertically aligned GO stems from an increased density of edges with a preferential orientation for membrane disruption. The importance of nanosheet penetration for cytotoxicity has direct implications for the design of engineering surfaces using GBNs.
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•Biosynthesis method using plant extract is more advantageous than chemical method.•The biomolecules in plants extracts affect particle size and shape of ZnO NPs.•Azo dyes toxicity ...can be due to their cleaved products in host mammals.•Photodegradation efficiency of ZnO NPs for azo dyes is limited by several factors.•Bactericidal efficacy of ZnO NPs is strongly affected by employed synthesis method.
These days, with the increasing problem of water contamination by effluents released from rising expansion of textile, leather, paper and ink industries and problems related to disease causing pathogenic microorganisms, the need for a substance with antimicrobial and photocatalytic activity is very high. Interesting properties of ZnO nanoparticles (NPs) such as non-toxicity, low cost, biocompatibility, chemical stability, thermal and photostability, high UV absorption ability have made it a promising photocatalyst for removing hazardous contaminants especially azo dyes in wastewater. However, the toxic nature of ZnO NPs for microbes, in particular, bacteria coupled with the properties mentioned have made it a preferable antimicrobial agent in medicine and food packaging for inhibiting microbial growth. In this review, the physical and chemical properties, synthesis approaches, antibacterial activity, and photocatalytic activity of ZnO NPs are discussed. Since many properties of ZnO NPs, and hence its application, depend on the synthesis method employed, focus is given on the biosynthesis of ZnO NPs from plant extracts. Moreover, factors affecting photocatalytic activity in the photocatalytic degradation of azo dyes in wastewater treatment as well as antibacterial activity of ZnO NPs are highlighted based on recent reports in the literature.
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Some novel 1,2,3-triazole-based pleuromutilin derivatives were designed. Compound 7c displayed antibacterial activities against S. aureus, MRSA and S. epidermidis with MIC values ...0.062 μg/mL, and molecular modeling was performed to further investigate the mechianism.
•A series of novel 1,2,3-triazole-based pleuromutilin derivatives were synthesized.•Compound 7c displayed highest potency with MIC values 0.0625 μg/mL against S. aureus, MRSA and S. epidermidis.•Killing kinetics test revealed that tested compound displayed concentration-dependent effect.•Molecular docking showed that three strong hydrogen bonds were formed between 7c and ribosomal residues.
A novel class of pleuromutilin derivatives possessing 1,2,3-triazole as the linker connected to phenyl analogues were designed. The antibacterial properties of the prepared compounds were assessed in vitro against five strains (E. coli, S. aureus, S. epidermidis, and E. faecalis). Most of the tested compounds displayed potent antibacterial activities against gram-positive bacteria and 14-O-2-(4-((2,4-dinitrophenoxy)-methyl-1H-1,2,3-triazol-1-yl) acetamide)-2-methylpropan-2-yl) thioacetylmutilin (7c) exerted antibacterial activities against S. aureus, MRSA and S. epidermidis with MIC values 0.0625 μg/mL, representing 64-fold, 4-fold and 8-fold higher than tiamulin respectively. Compound 6e, 7c and 8c were chosen to carry out killing kinetics, which exhibited concentration-dependent effect. Subsequently, molecular modeling was conducted to further explore the binding of compound 6e, 7a, 7c, 8c and tiamulin with 50S ribosomal subunit from deinococcus radiodurans. The investigation revealed that the main interactions between compound 7c and the ribosomal residues were three hydrogen bonds, π-π, and p-π conjugate effects. Additionally, the free binding energy and docking score of 7c with the ribosome demonstrated the lowest values of −11.90 kcal/mol and −7.97 kcal/mol, respectively, consistent with its superior antibacterial activities.
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•Nanofibrous wound dressing with comparable mechanical property to soft tissue was designed.•The dressing showed good electroactivity and anti-oxidant ability.•The dressing exhibited ...good biocompatibility and effective antibacterial activity.•The dressing significantly accelerated the healing process of full-thickness skin wound.
Developing a novel nanofibrous wound dressing with multi-functional properties, integrating suitable mechanical property, electroactivity, anti-oxidant and inherent antibacterial activity to promote wound healing process is urgently desired, which could meet the increasing requirements of clinical needs. Herein, a series of antibacterial, anti-oxidant and electroactive nanofibrous membranes were fabricated by electrospinning poly(ε-caprolactone) (PCL) and quaternized chitosan-graft-polyaniline (QCSP) polymer solutions which combined the good mechanical property of PCL and multi-functionality of QCSP. The nanofibrous wound dressings exhibited electroactivity, similar mechanical properties to soft tissue, free radical scavenging capacity, antibacterial property, and biocompatibility. In particular, PCL/QCSP15 (15 wt% of QCSP in the sample) showed a good balanced ability between antibacterial activity and cell proliferation, which significantly accelerated the healing process of wound in a mouse full-thickness wounds defect model than commercial dressing (Tegaderm™ Film) and pure PCL (PCL/QCSP0) nanofibrous membrane. Moreover, the histopathological examination and immunofluorescence staining showed that the wounds treated by PCL/QCSP15 nanofiber dressing exhibited higher collagen deposition, granulation tissue thickness, and more angiogenesis. In one word, these antibacterial, anti-oxidant, electroactivity nanofibrous membranes showed promising applications for full-thickness skin repair.
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