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Abstract The environmental-friendly hydrothermal method has been carried out to synthesize Bi2WO6 and g-C3N4/PVP doped Bi2WO6 nanorods (NRs) by incorporating different concentrations of graphitic carbon nitride (g-C3N4) as well as a specified quantity of polyvinylpyrrolidone (PVP). Bi2WO6 doped with g-C3N4 provides structural and chemical stability, reduces charge carriers, degrades dyes, and, owing to lower bandgap energy, is effective for antibacterial, catalytic activity, and molecular docking analysis. The purpose of this research is the treatment of polluted water and to investigate the bactericidal behavior of a ternary system. The catalytic degradation was performed to remove the harmful rhodamine B (RhB) dye using NaBH4 in conjunction with prepared NRs. The specimen compound demonstrated antibacterial activity against Escherichia coli (E. coli) at both high and low concentrations. Higher doped specimens of g-C3N4/PVP-doped Bi2WO6 exhibited a significant improvement in efficient bactericidal potential against E. coli (4.55 mm inhibition zone). In silico experiments were carried out on enoyl-[acylcarrier-protein] reductase (FabI) and β-lactamase enzyme for E. coli to assess the potential of Bi2WO6, PVP doped Bi2WO6, and g-C3N4/PVP-doped Bi2WO6 NRs as their inhibitors and to justify their possible mechanism of action.

Abstract Various concentrations of samarium‐grafted‐carbon nitride (Sm‐g‐C3N4) doped‐bismuth oxobromide (BiOBr) quantum dots (QDs) are prepared by the co‐precipitation method. Elemental evaluation, morphological, optical, and functional group assessment are studied employing characterization techniques. Based on the XRD pattern analysis, it is determined that BiOBr exhibits a tetragonal crystal structure. The electronic spectroscopy revealed an absorption peak for BiOBr at 315 nm and the bandgap energy (Eg) decreasing from 3.9 to 3.8 eV with the insertion of Sm‐g‐C3N4. The presence of vibrational modes related to BiOBr at 550 cm−1 is confirmed through FTIR spectra. TEM revealed that pure BiOBr possessed non‐uniform QDS, and agglomeration increased with the addition of Sm‐g‐C3N4. The catalytic performance of Sm‐g‐C3N4 into BiOBr (6 mL) in a neutral medium toward rhodamine B exhibited excellent results (99.66%). The bactericidal activity is evaluated against multi‐drug resistance (MDR) Escherichia coli once the surface area is increased by dopant and the measured inhibition zone is assessed to be 3.65 mm. Molecular docking results supported the in vitro bactericidal potential of Sm‐g‐C3N4 and Sm‐g‐C3N4 doped‐BiOBr as DNA gyraseE. coli inhibitors. This study shows that the novel Sm‐g‐C3N4 doped‐BiOBr is a better catalyst that increases specific semiconductor's catalytic activity (CA).

Abstract Microplastic pollution has adversely affected the aquatic ecosystem, living creatures, and human health. Several studies in Malaysia have provided baseline information on the existence of microplastics in surface water, ingestion by marine life and sediment. Also, humans are exposed to microplastic due to consumption of contaminated abiotic and biotic products, such as processed seafood. Nonetheless, knowledge is still scarce among Malaysian on the potential remediation and pollution management of microplastics, which poses a significant challenge to preserve a good environmental status. Green technologies also other alternative to mitigate the contamination of microplastics for sustainable future. Hence, this review aims to provide an overview of microplastic's occurrence, fate, and implications in Malaysia's aquatic environment. Detection of microplastics from the water surface, ingestion by aquatics, and sediment samples are highlighted. Available different treatment processes toward microplastic remediation are also discussed. Additionally, the potential challenges, current perspective for plastic management in Malaysia, as well as green strategies for reducing microplastic contamination are also put forward. The goal of this work is to improve the understanding of the seriousness of microplastic contamination in aquatic environments, thus encouraging key concerns that need to be investigated further.

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Abstract A wide range of hard contaminants in wastewater is generated from different industries as byproducts of the organic compound. In this review, various metal oxide‐based nanomaterials are employed for the photocatalytic removal of malachite green (MG) dye from wastewater. Some cost‐effective and appropriate testing conditions are used for degrading these hard dyes to get higher removal efficiency. The effects of specific parameters are considered such as how the catalyst is made, how much dye is in the solution at first, how much nanocatalyst is needed to break down the dye, the initial pH of the dye solution, the type of light source used, the year of publications, and how long the dye has to be exposed to light to be removed. This study suggests that Scopus‐based core collected data employ bibliometric methods to provide an objective analysis of global MG dye from 2011 to 2022 (12 years). The Scopus database collects all the information (articles, authors, keywords, and publications). For bibliometric analysis, 658 publications are retrieved corresponding to MG dye photodegradation, and the number of publications increases annually. A bibliometric study reveals a state‐of‐art review of metal oxide‐based nanomaterials' effects on photocatalytic degradation of MG dyes (12 years).

Huge plastic consumption and depletion of fossil fuels are at the top of the world's environmental and energy challenges. The scientific community has tackled these issues through different approaches. Catalytic pyrolysis of plastic wastes to valuable products has been proved as a sustainable route which fits with the circular economy aspects. The design of catalytic materials is the central factor for performing the catalytic conversion of plastic wastes. This review aims to conduct a Bibliometric analysis of the pyrolysis of plastic wastes and non-precious-based catalysts by mapping research studies over the last fifty years. The analysis was developed via VOSviewer and RStudio tools. It showed the historical progress regarding plastic waste pyrolysis to produce valuable products and chemicals worldwide. The research shows that the top five countries with the highest citations and publications in this field were Spain, China, England, the USA and India. The Journal of Analytical and Applied Pyrolysis had the most comprehensive coverage of plastic waste. The relationship between the catalyst and the mechanism of plastic waste can influence the production yield and selectivity. The research gap and underrepresented research topics were identified, and previous research studies on developing non-precious-based catalysts that were most relevant to the current topic were reviewed and discussed. The challenges and perspectives on catalyst preparation and development for material complexity were critically discussed. Challenges of previous studies and directions for future research were provided. This report might guide the reader to take a general look at plastic waste valorization by pyrolysis and easily understand the main challenges.

In this study, MoO3 nanostructures were prepared, doped with various concentrations of graphene oxide (2 and 4% GO) and a fixed amount of polyvinylpyrrolidone (PVP) using the co-precipitation method. The motive of this study was to examine the catalytic and antimicrobial efficacy with evidential molecular docking analyses of GO/PVP-doped MoO3. GO and PVP were utilized as doping agents to reduce the exciton recombination rate of MoO3 by providing more active sites that increase the antibacterial activity of MoO3. The prepared binary dopant (GO and PVP)-dependent MoO3 was used as an effective antibacterial agent against Escherichia coli (E. coli). Notably, 4% GO/PVP-doped MoO3 showed good bactericidal potential against E. coli at higher concentrations in comparison to ciprofloxacin. Furthermore, in silico docking revealed the possible inhibitory impact of the synthesized nanocomposites on folate and fatty acid synthesis enzymes, dihydrofolate reductase and enoyl-[acyl carrier protein] reductase, respectively.

Abstract The development of efficient catalysts with a large number of active sites, tunable bandgap, and large surface area has been very challenging. In addition, a significant bottleneck in the application of catalysts for water treatment is their dissolution under extreme conditions, such as highly acidic or highly alkaline conditions that lead to poor application of the reported materials in real‐world applications. In this study, the lanthanum (La)‐doped molybdenum disulfide (MoS2) nanosheets are reported for efficient breakdown of toxic pollutants from wastewater under a wide pH range from strongly alkaline to strongly acidic solutions. The La‐MoS2 nanosheets (NSs) are prepared by a facile hydrothermal approach using a two‐step methodology. A redshift is observed upon La doping, indicating that the bandgap is lowered after La doping in MoS2. The changes in bandgap and electronic structure are further investigated using the density functional theory (DFT), which reveal that doping of La introduces new states within the bandgap region, allowing for further induced energy transitions. The La‐MoS2, having a doping concentration of 2%, exhibits the highest catalytic activity against methylene blue (MB) in neutral, acidic, and alkaline solutions, as well as substantial inhibitory activity for bacterial strains such as Escherichia coli (E. coli). In summary, the modified catalyst provides a pathway to design highly efficient catalysts for all pH range water treatment as well as good activity against microbes.

This research lays the groundwork for preparing graphene oxide (GO)-doped CaO nanocomposites for efficient antibacterial potential and dye degradation. The study aimed to reduce the recombination rate of the electron hole (e−/h+) of CaO and improve charge transfer. This issue can be minimized by doping high-surface area GO into CaO quantum dots (QDs). Herein, the one-pot co-precipitation technique has prepared various concentrations (1, 3, and 5 wt%) of GO-doped CaO. Characterization techniques were used to investigate optical, elemental analysis, microstructural, functional, and morphological properties. The addition of GO into QDs showed excellent catalytic activity (CA) to control sample CaO against methylene blue (MB) in basic and acidic media compared to the neutral media. The synergistic effect of morphological alternation attributed to an increase in the mechanism of CA upon doping. Various concentrations of GO to QDs promised remarkable bactericidal potency against Escherichia coli.

In this research work, pristine and various concentrations (2.4 wt%) of graphene oxide (GO)/carbon sphere (CS)–doped Al2O3 nanostructures (NSs) were synthesized with the chemical sol–gel method. Aluminum oxide (Al2O3) exhibits quick recombination of electrons and holes with a low specific surface to limit catalytic and antibacterial activities. Al2O3 doped with CS is good in wastewater treatment and reduces the size of NSs. The incorporation of graphene oxide (GO) into Al2O3 at different concentrations (2 and 4 wt%) enhances both the structural and chemical stabilities of the resulting material while concurrently decreasing the number of charge carriers and reducing the band gap energy. This modified Al2O3-GO composite exhibits promising potential for utilization in dye degradation and antibacterial activity. A series of characterizations were performed to investigate the structural, morphological, and optical properties. The NSs exhibited excellent catalytic activity (CA) against rhodamine B (RhB) dye in acidic, basic, and neutral media. The antimicrobial activity was tested against Escherichia coli. Pairs of electrons and holes are the primary building blocks for the production of reactive oxygen species (ROS), which causes bacteria to die. The significant inhibition zones against E. coli were calculated to be approximately 5.65 mm when compared to ciprofloxacin. Moreover, in silico investigations have revealed the possible inhibitory impact of produced nanomaterials (GO/CS-doped Al2O3) on DNA gyrase and FabI enzymes of fatty acid biosynthesis.

The emergence of multi-drug resistance (MDR) in aquatic pathogens and the presence of cationic dyes are the leading causes of water contamination on a global scale. In this context, nanotechnology holds immense promise for utilizing various nanomaterials with catalytic and antibacterial properties. This study aimed to evaluate the catalytic and bactericidal potential of undoped and Sr-doped Cr2O3 nanostructures (NSs) synthesized through the co-precipitation method. In addition, the morphological, optical, and structural properties of the resultant NSs were also examined. The optical bandgap energy of Cr2O3 has been substantially reduced by Sr doping, as confirmed through extracted values from absorption spectra recorded by UV-Vis studies. The field-emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) micrographs illustrate that the composition of Cr2O3 primarily consisted of agglomerated, irregularly shaped NSs with a morphology resembling nanoflakes. Moreover, the presence of Sr in the lattice of Cr2O3 increased the roughness of the resulting NSs. The catalytic activity of synthesized NSs was analyzed by their reduction ability of Rhodamine B (RhB) dye in the dark under different pH conditions. Their antibacterial activity was evaluated against MDR Escherichia coli (E. coli). Sr doping increased antibacterial efficiency against MDR E. coli, as indicated by inhibition zone measurements of 10.15 and 11.75 mm at low and high doses, respectively. Furthermore, a molecular docking analysis was conducted to determine the binding interaction pattern between NSs and active sites in the target cell protein. The findings corroborated antimicrobial test results indicating that Sr-Cr2O3 is the most effective inhibitor of FabH and DHFR enzymes.

Breast cancer is considered the second-leading cancer after lung cancer and is the most prevalent cancer among women globally. Currently, cancer immunotherapy via vaccine has gained great attention due to specific and targeted immune cell activity that creates a potent immune response, thus providing long-lasting protection against the disease. Despite peptides being very susceptible to enzymatic degradation and poor immunogenicity, they can be easily customized with selected epitopes to induce a specific immune response and particulate with carriers to improve their delivery and thus overcome their weaknesses. With advances in nanotechnology, the peptide-based vaccine could incorporate other components, thereby modulating the immune system response against breast cancer. Considering that peptide-based vaccines seem to show remarkably promising outcomes against cancer, this review focuses on and provides a specific view of peptide-based vaccines used against breast cancer. Here, we discuss the benefits associated with a peptide-based vaccine, which can be a mainstay in the prevention and recurrence of breast cancer. Additionally, we also report the results of recent trials as well as plausible prospects for nanotechnology against breast cancer.

Antibiotics and non-steroidal anti-inflammatory drugs (NSAIDs) are among the top pharmaceutical contaminants that have been often found in the aquatic environment. The presence of these contaminants in the aquatic environment is of great concern since it has a negative impact on both ecology and human health. In contrast to other tertiary treatments, adsorption stands out as a viable treatment approach since it provides benefits such as easier operating conditions with no byproduct formation. Commercial activated carbon is widely researched as a pharmaceutical adsorbent, but its large-scale applicability is constrained by its high cost. Agricultural waste also contains a large amount of various functional groups, which may be adapted to surface modification to increase its adsorption ability. In this regard, this study is designed to review the recent progress of efficient adsorbents derived from various agricultural wastes for the removal of antibiotics and NSAIDs contaminants from water bodies. Adsorbents made from agricultural waste have important benefits over commercial activated carbon for the reduction in waste while controlling water pollution.

Recently, the research on the remediation of aqueous organic pollutants over visible-light-active photocatalysts has got much attention. Therefore, this study reports the fabrication of visible-light-active Co3O4-Bi2O3 heterojunction photocatalyst for the photodegradation of rhodamine B dye. The Co3O4-Bi2O3 heterojunction was synthesized by the coprecipitation method and characterized by XRD, EDS, SEM, TEM, TGA, and FTIR. The as-prepared Co3O4-Bi2O3 heterojunction was utilized as a photocatalyst for the abatement of rhodamine B dye. It was observed that Co3O4-Bi2O3 showed the best catalytic performance with ∼92% degradation of rhodamine B dye than Co3O4 and Bi2O3 with 14 and 34% removal of rhodamine B dye, respectively. The rate constant for Co3O4-Bi2O3 catalyzed photodegradation of rhodamine B was 6 times and 3 times higher than the rate constant for Co3O4 catalyzed and Bi2O3 catalyzed photodegradation of rhodamine B, respectively. The as-prepared Co3O4-Bi2O3 exhibited the highest catalytic performance at pH 8.

A key element in ensuring successful immunization is the efficient delivery of vaccines. However, poor immunogenicity and adverse inflammatory immunogenic reactions make the establishment of an efficient vaccine delivery method a challenging task. The delivery of vaccines has been performed via a variety of delivery methods, including natural-polymer-based carriers that are relatively biocompatible and have low toxicity. The incorporation of adjuvants or antigens into biomaterial-based immunizations has demonstrated better immune response than formulations that just contain the antigen. This system may enable antigen-mediated immunogenicity and shelter and transport the cargo vaccine or antigen to the appropriate target organ. In this regard, this work reviews the recent applications of natural polymer composites from different sources, such as animals, plants, and microbes, in vaccine delivery systems.

Natural polymers have received a great deal of interest for their potential use in the encapsulation and transportation of pharmaceuticals and other bioactive compounds for disease treatment. In this perspective, the drug delivery systems (DDS) constructed by representative natural polymers from animals (gelatin and hyaluronic acid), plants (pectin and starch), and microbes (Xanthan gum and Dextran) are provided. In order to enhance the efficiency of polymers in DDS by delivering the medicine to the right location, reducing the medication’s adverse effects on neighboring organs or tissues, and controlling the medication’s release to stop the cycle of over- and under-dosing, the incorporation of Fe3O4 magnetic nanoparticles with the polymers has engaged the most consideration due to their rare characteristics, such as easy separation, superparamagnetism, and high surface area. This review is designed to report the recent progress of natural polymeric Fe3O4 magnetic nanoparticles in drug delivery applications, based on different polymers’ origins.

Full factorial experimental design with 32 runs was used to investigate the significant and interaction variable of the reaction parameters on phenol steam reforming toward hydrogen production. Effects of selected factors on the phenol conversion (Y1) and hydrogen yield (Y2) were evaluated. These factors were as follows: (A) temperature (500 and 800 °C); (B) feed flow rate (0.16–0.46 mL/min); (C) catalyst weight (0.1–0.3 g); (D) Ni-Co ratio (0–1); and (E) phenol concentration in the feed (2–10 wt %). Ni and Co over ZrO2 support for catalytic performance of phenol steam reforming (SRP) was prepared by the impregnation method. The result indicated that all the main independent variables had significant influence on the dependent variable of Y1 and Y2 with a range of 2.7%–96.8% and 21.4%–72.4%, respectively. Additionally, some interaction variables like AE, BE, CE, and DE have also influenced the Y1 and Y2 responses. This design showed that the best initial conditions that produced maximum Y1 and Y2 responses were at 800 °C, 0.16 mL/min feed flow rate, 0.3 g of catalyst, 0 ratio of Ni-Co (Co/ZrO2), and 10 wt % of phenol in the feed, where the phenol conversion was predicted to be 94.98% and the hydrogen yield was predicted to be 67.4%. Within the limits the variables were examined, a regression model which well-fitted the experimental data was proposed. The regression model were reduced to simplify and to get the significant regression coefficient with p-value less than 0.05.