Environmentally benign production of cupric oxide nanoparticles and various utilizations of their polymeric hybrids in different technologies

Histotoxicity induced by copper oxide nanoparticles (CuO-NPs) on developing mice (Mus musculus)

The wide range of applications of nanoparticles (NPs) in various industries have led to serious consequences in terms of teratogenic toxicity. The aim of current work was to evaluate the teratogenic effects of copper oxide (CuO) nanoparticles in albino mice.In this experimental study, after mating, inseminated 40 female mice were divided randomly into 4 pools (1 control and 3 experimental), ten each. Doses were administered intravenously (We followed the protocol by Yaqub et al. (2018), intravenous application is faster route as compared to oral dosage)to all the experimental groups on the 6th day of gestation (GD), dose concentrations were 200, 133.3 and 100 mg/kg body weights respectively.The doses were prepared in sequence (1/2, 1/3, 1/4 0f LD50) according to already published work. The effects of CuO-NPs show linear relationship with the above sequence. The control group was administered only with distilled water.The gravid females were sacrificed through cervical disruption at the 18th day of gestation, fetuses were removed and divided into four sets (pools) for morphometric, morphological and histological studies. Data were subjected to statistical analysis by using Tukey's test in light of ANOVA at p < 0.05 level of significance. Findings of the present study showed that CuO-NPs various concentrations affect developmental abnormalities i.e.runt embryos, resorbed uteri, exencephaly, hygroma, macroglossia, micromelia, open eye, omphalocoel, scoliosis, kyphosis and kinked tail. It is concluded that exposure to CuO-NPs may potentially lead to the developmental deformities in mice.

A robust carbon dot-based antibacterial CDs-PVA film as a wound dressing for antibiosis and wound healing

Developing highly effective antibacterial films to promote wound healing remains a huge challenge. Herein, homogeneous and self-standing CDs-PVA composite films (PVA₃, PVA₅ and PVA₈) were constructed by doping various mass ratios (3, 5 and 8 wt%) of carbon dots (CDs) into polyvinyl alcohol (PVA), which had no cracks or macroscopic defects. Moreover, the robust mechanical strength and flexibility enabled them to be cut into diverse patterns as required, which provided unique advantages for being employed as a wound dressing. PVA₅ and PVA₈ were powerful broad-spectrum bactericides and they could kill both Gram-negative bacteria and Gram-positive bacteria like Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) with the antibacterial efficacy over 90.0%. More significantly, the biocompatible films could be readily processed into a "band-aid" type dressing for wound healing. The PVA₅ band-aids were just pasted on the wounds for two days and then removed, and the wounds were completely closed after fourteen days. Neither introducing any metals or antibiotics, nor with the help of any external activation, these kinds of CD-based films have the strengths of low cost, being easy to use, excellent biocompatibility and outstanding antibacterial performance, and are desirable wound dressings for various skin injuries.

Facile synthesis of CuO/g-C3N4 nanolayer composites with superior catalytic reductive degradation behavior

The cupric oxide (CuO) loaded graphitic carbon nitride (g-C₃N₄) nanocomposites (CuO/g-C₃N₄) were prepared by a facile calcination method. The formation of monoclinic CuO nanocrystals along with g-C₃N₄ was confirmed by X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopic analysis. X-ray photoelectron spectral (XPS) analysis further confirms the formation of CuO/g-C₃N₄. Distribution of CuO stone-like crystalline nanoparticles on g-C₃N₄ nanosheets was observed by transmission electron microscopic images. The influence of CuO loading on the optical property of g-C₃N₄ was determined by ultraviolet (UV)-visible absorption and photoluminescence (PL) spectral analysis. Band gap was decreased from 2.7 to 2.3 eV by the addition of CuO nanoparticles. The catalytic performance of the synthesized samples in 4-nitrophenol (4-NP) and methyl orange (MO) reduction was evaluated. The 5 wt% CuO/g-C₃N₄ showed 99.5% (7 min) and 99.7% (4 min) reduction efficiency for 4-NP and MO respectively. The 5 wt% CuO/g-C₃N₄ could become a potential catalyst in the chemical treatment of organic pollutants.

Emerging 2D Copper-Based Materials for Energy Storage and Conversion: A Review and Perspective

2D materials have shown great potential as electrode materials that determine the performance of a range of electrochemical energy technologies. Among these, 2D copper-based materials, such as Cu-O, Cu-S, Cu-Se, Cu-N, and Cu-P, have attracted tremendous research interest, because of the combination of remarkable properties, such as low cost, excellent chemical stability, facile fabrication, and significant electrochemical properties. Herein, the recent advances in the emerging 2D copper-based materials are summarized. A brief summary of the crystal structures and synthetic methods is started, and innovative strategies for improving electrochemical performances of 2D copper-based materials are described in detail through defect engineering, heterostructure construction, and surface functionalization. Furthermore, their state-of-the-art applications in electrochemical energy storage including supercapacitors (SCs), alkali (Li, Na, and K)-ion batteries, multivalent metal (Mg and Al)-ion batteries, and hybrid Mg/Li-ion batteries are described. In addition, the electrocatalysis applications of 2D copper-based materials in metal-air batteries, water-splitting, and CO₂ reduction reaction (CO₂ RR) are also discussed. This review also discusses the charge storage mechanisms of 2D copper-based materials by various advanced characterization techniques. The review with a perspective of the current challenges and research outlook of such 2D copper-based materials for high-performance energy storage and conversion applications is concluded.

Chitosan-Grafted Polyacrylic Acid-Doped Copper Oxide Nanoflakes Used as a Potential Dye Degrader and Antibacterial Agent: In Silico Molecular Docking Analysis

This study examined the catalytic and bactericidal properties of polymer-doped copper oxide (CuO). For this purpose, a facile co-precipitation method was used to synthesize CuO nanostructures doped with CS-g-PAA. Various concentrations (2, 4, and 6%) of dopants were systematically incorporated into a fixed amount of CuO. The prepared samples were analyzed by different optical, structural, and morphological characterizations. Field emission scanning electron microscopy and transmission electron microscopy micrographs indicated that doping transformed CuO's agglomerated rod-like surface morphology to form nanoflakes. UV-vis spectroscopy revealed that the optical spectra of the samples exhibit a redshift after doping, leading to a decrease in band gap energy from 3.3 to 2.5 eV. The purpose of the study was to test the catalytic activity of pristine and CS-g-PAA doped CuO for the degradation of methylene blue in acidic, basic, and neutral conditions using NaBH₄ as a reducing agent in an aqueous medium. Furthermore, antibacterial activity was evaluated against Gram-positive and Gram-negative bacteria, namely, Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Overall, enhanced bactericidal performance was observed upon doping CS-g-PAA into CuO, i.e., 4.25-6.15 and 4.40-8.15 mm against S. aureus and 1.35-4.20 and 2.25-5.25 mm against E. coli at the lowest and highest doses, respectively. The relevant catalytic and bactericidal action mechanisms of samples are also proposed in the study. Moreover, in silico molecular docking studies illustrated the role of these prepared nanomaterials as possible inhibitors of FabH and FabI enzymes of the fatty acid biosynthetic pathway.

Development of Environmentally Friendly Biocidal Coatings Based on Water-soluble Copolymers for Air-cleaning Filters

Air pollution by pathogens has posed serious concern on global health during the last decades, especially since the breakout of the last pandemic. Therefore, advanced high-efficiency techniques for air purification are highly on demand. However, in air-filtering devices, the prevention of secondary pollution that may occur on the filters remains a challenge. Toward this goal, in the present work, we demonstrate a facile and eco-friendly process for the biocidal treatment of commercial high-efficiency particulate air filters. The antibacterial filters were successfully prepared through spray coating of aqueous solutions based on biocidal water-soluble polymers, poly(sodium 4-styrene sulfonate-co-cetyl trimethylammonium 4-styrene sulfonate-co-glycidyl methacrylate) [P(SSNa24-co-SSAmC₁₆56-co-GMA20)] and poly(2-dimethylaminoethyl)methacrylate. Significantly, an optimized green route was developed for the synthesis of the used polymers in aqueous conditions and their stabilization through cross-linking reaction, leading to biocidal air filters with long-lasting activity. The developed coatings presented strong and rapid antibacterial activity against Staphylococcus aureus (in 5 min) and Escherichia coli (in 15 min). Moreover, the cytotoxicity test of the polymeric materials toward Α549 lung adenocarcinoma cells indicated very low toxicity as they did not affect either the cell growth or cell morphology. The above-mentioned results together with the scalable and easy-to-produce green methodology suggest that these materials can be promising candidates as filter coatings for use on air-purification devices.

Bioengineering of CuO porous (nano)particles: role of surface amination in biological, antibacterial, and photocatalytic activity

Nanotechnology is one of the most impressive sciences in the twenty-first century. Not surprisingly, nanoparticles/nanomaterials have been widely deployed given their multifunctional attributes and ease of preparation via environmentally friendly, cost-effective, and simple methods. Although there are assorted optimized preparative methods for synthesizing the nanoparticles, the main challenge is to find a comprehensive method that has multifaceted properties. The goal of this study has been to synthesize aminated (nano)particles via the Rosmarinus officinalis leaf extract-mediated copper oxide; this modification leads to the preparation of (nano)particles with promising biological and photocatalytic applications. The synthesized NPs have been fully characterized, and biological activity was evaluated in antibacterial assessment against Bacillus cereus as a model Gram-positive and Pseudomonas aeruginosa as a model Gram-negative bacterium. The bio-synthesized copper oxide (nano)particles were screened by MTT assay by applying the HEK-293 cell line. The aminated (nano)particles have shown lower cytotoxicity (~ 21%), higher (~ 50%) antibacterial activity, and a considerable increase in zeta potential value (~ + 13.4 mV). The prepared (nano)particles also revealed considerable photocatalytic activity compared to other studies wherein the dye degradation process attained 97.4% promising efficiency in only 80 min and just 7% degradation after 80 min under dark conditions. The biosynthesized copper oxide (CuO) (nano)particle's biomedical investigation underscores an eco-friendly synthesis of (nano)particles, their noticeable stability in the green reaction media, and impressive biological activity.

Fabrication of air filters with advanced filtration performance for removal of viral aerosols and control the spread of COVID-19

COVID-19 is caused via the SARS-CoV-2 virus, a lipid-based enveloped virus with spike-like projections. At present, the global epidemic of COVID-19 continues and waves of SARS-CoV-2, the mutant Delta and Omicron variant which are associated with enhanced transmissibility and evasion to vaccine-induced immunity have increased hospitalization and mortality, the biggest challenge we face is whether we will be able to overcome this virus? On the other side, warm seasons and heat have increased the need for proper ventilation systems to trap contaminants containing the virus. Besides, heat and sweating accelerate the growth of microorganisms. For example, medical staff that is in the front line use masks for a long time, and their facial sweat causes microbes to grow on the mask. Nowadays, efficient air filters with anti-viral and antimicrobial properties have received a lot of attention, and are used to make ventilation systems or medical masks. A wide range of materials plays an important role in the production of efficient air filters. For example, metals, metal oxides, or antimicrobial metal species that have anti-viral and antimicrobial properties, including Ag, ZnO, TiO₂, CuO, and Cu played a role in this regard. Carbon nanomaterials such as carbon nanotubes, graphene, or derivatives have also shown their role well. In addition, natural materials such as biopolymers such as alginate, and herbal extracts are employed to prepare effective air filters. In this review, we summarized the utilization of diverse materials in the preparation of efficient air filters to apply in the preparation of medical masks and ventilation systems. In the first part, the employing metal and metal oxides is examined, and the second part summarizes the application of carbon materials for the fabrication of air filters. After examination of the performance of natural materials, challenges and progress visions are discussed.

Recent advancements in synthesis and drug delivery utilization of polysaccharides-based nanocomposites: The important role of nanoparticles and layered double hydroxides

Drug delivery systems are explained as methods to deliver a specific drug to desired organs, tissues, and cells for drug release to diseases treatment. Recently, considerable development has been interested in stimuli-responsive nano-systems, which respond to the essential pathological and physicochemical issues in diseased sites. During the last decades, researchers in the world presented, investigated, and implemented novel different nanomaterials with a focus on developing drug delivery. Polysaccharides including chitosan, alginate, hyaluronic acid, gums, and cellulose, as natural bio-materials, are suitable candidates for designing and formulations of these nano-systems because of the outstanding merits such as bio-compatibility, bio-degradability, non-toxicity, and gelling characteristics. On the other side, nanoparticles including metals (Au, Ag), metal oxides (Fe₃O₄, ZnO, CuO), or non-metal oxides (SiO₂) and also, layered double hydroxides nanostructures have appealed significant consideration in the fields of biomedical therapeutics and cancer therapy owing to the bio-compatibility, great surface area, good chemical and mechanical features, and also proper magnetic characteristics. This comprehensive review provides an overview of current advancements in drug delivery strategies, and manufacturing methods using chitosan, alginate, hyaluronic acid, gums, and also, metals, metal oxides, non-metal oxides, and LDHs for delivery system uses.

Copper Rich Composite Materials Based on Carboxylic Cation Exchangers and Their Thermal Transformation

The effect of a cupric deposit (Cu2+, CuO) on the thermal decomposition of carboxylic cation exchangers (CCEs) is not known, and such studies may have practical significance. CCEs have a very high ion exchange capacity, so an exceptionally large amount of CuO (which is a catalyst) can be precipitated inside them. Two CCEs, macroreticular (Amberlite IRC50) and gel-like (Amberlite IRC86), served as a polymeric support to obtain copper-rich hybrid ion exchangers. Composites with CuO particles inside a polyacrylic matrix (up to 35.0 wt% Cu) were obtained. Thermal analyses under air and under N2 were performed for CCEs in the H+ and Cu2+ form with and without a CuO deposit. The results of sixteen experiments are discussed based on the TG/DTG curves and XRD patterns of the solid residues. Under air, the cupric deposit shifted the particular transformations and the ultimate polymeric matter decomposition (combustion) toward lower temperatures (even about 100-150 °C). Under N2, the reduction of the cupric deposit to metallic copper took place. Unique composite materials enriched in carbonaceous matter were obtained, as the products of polymeric matrix decomposition (free radicals and hydrogen) created an additional amount of carbon char due to the utilization of a certain amount of hydrogen to reduce Cu (II) to Cu0.

Bioinspired triangular ZnO nanoclusters synthesized by Argyreia nervosa nascent leaf extract for the efficient electrochemical determination of vitamin C

This work deals with the synthesis of bioinspired triangular ZnO nanoclusters (bT-ZnO NCs) from Argyreia nervosa nascent leaf extract for their effective antibacterial activity and further utilization as a platform for the electrocatalytic determination of ascorbic acid (AA; vitamin C) for applications in the agricultural domain. The structural, optical, and morphological characteristics of the synthesized bT-ZnO NCs were analyzed by UV-vis, FT-IR, XRD, AFM, SEM, TEM, HR-TEM, and EDX techniques. After this, bT-ZnO NCs were electrophoretically deposited onto an indium-tin-oxide (ITO) glass substrate and assessed for the electro-oxidation of AA by cyclic voltammetry (CV), and from this it was proven that bT-ZnO NCs had a very high electrochemical sensitivity of 29.88 μA cm⁻² toward AA and a low limit of detection of 0.5321 mM under the optimized experimental conditions. Thus, it provides a potential sensing platform for electrochemical studies to detect AA. Moreover, bT-ZnO NCs were preliminarily investigated for their antibacterial activity, and the obtained results showed that the bT-ZnO NCs have potency as an antibacterial agent.

This study reports the synthesis of bioinspired triangular ZnO nanoclusters (bT-ZnO NCs) from Argyreia nervosa nascent leaf extract and their use in the agricultural domain for the label-free detection of vitamin C and its antibacterial efficiency.

Protection, disinfection, and immunization for healthcare during the COVID-19 pandemic: Role of natural and synthetic macromolecules

The world is trying to improve public health while the outbreak of the COVID-19 is at its worst. So far, countless people have died from the COVID-19 disease and it is still a serious threat to human health. Synthetic and natural polymers are unavoidable materials in the healthcare sector. During the COVID-19 outbreak, diverse medical equipment and devices were designed and developed by using these macromolecules for the protection, disinfection, and immunization applications. Synthetic polymers such as polypropylene, polystyrene, poly(lactic acid), poly(ethylene terephthalate), and so forth have been successfully applied for the design and fabrication of diverse face masks, shields, anti-viral coatings, as well as diagnostic kits. Natural polymers having great features such as biodegradability and environmentally friendly are made from algae, plants, and animals. These polymers including sodium alginate, chitosan, cellulose, and gums have been shown a critical role in the fabrication of personal protective equipment, immunosensors, and anti-viral spray for control and fight against COVID-19. Besides, the problem of plastic waste can be solved by replacing them with natural polymers. This mini-review aims to show the application of polymer-based materials during the COVID-19 epidemic.

State-of-the-art of 3D printing technology of alginate-based hydrogels-An emerging technique for industrial applications

Recently, three-dimensional (3D) printing (also known as additive manufacturing) has received unprecedented consideration in various fields owing to many advantages compared to conventional manufacturing equipment such as reduced fabrication time, one-step production, and the ability for rapid prototyping. This promising technology, as the next manufacturing revolution and universal industrial method, allows the user to fabricate desired 3D objects using a layer-by-layer deposition of material and a 3D printer. Alginate, a versatile polysaccharide derived from seaweed, is popularly used for this advanced bio-fabrication technique due to its printability, biodegradability, biocompatibility, excellent availability, low degree of toxicity, being a relatively inexpensive, rapid gelation in the presence of Ca²⁺ divalent, and having fascinating chemical structure. In recent years, 3D printed alginate-based hydrogels have been prepared and used in various fields including tissue engineering, water treatment, food, electronics, and so forth. Due to the prominent role of 3D printed alginate-based materials in diverse fields. So, this review will focus and highlight the latest and most up-to-date achievements in the field of 3D printed alginate-based materials in biomedical, food, water treatment, and electronics.

Recent breakthroughs of antibacterial and antiviral protective polymeric materials during COVID-19 pandemic and after pandemic: Coating, packaging, and textile applications

The global epidemic owing to COVID-19 has generated awareness to ensuring best practices for avoiding the microorganism spread. Indeed, because of the increase in infections caused by bacteria and viruses such as SARS-CoV-2, the global demand for antimicrobial materials is growing. New technologies by using polymeric systems are of great interest. Virus transmission by contaminated surfaces leads to the spread of infectious diseases, so antimicrobial coatings are significant in this regard. Moreover, antimicrobial food packaging is beneficial to prevent the spread of microorganisms during food processing and transportation. Furthermore, antimicrobial textiles show an effective role. We aim to provide a review of prepared antimicrobial polymeric materials for use in coating, food packaging, and textile during the COVID-19 pandemic and after pandemic.

Tunable electrochemistry and efficient antibacterial activity of plant-mediated copper oxide nanoparticles synthesized by Annona squamosa seed extract for agricultural utility

The present report deals with the synthesis of plant-mediated copper oxide nanoparticles (pm-CuO NPs) from Annona squamosa aqueous seed extract for effective antibacterial activity and the further utilization of this as a platform for the electrocatalytic determination of hydrogen peroxide (H₂O₂) for applications in the agricultural domain. The structural, optical and morphological characteristics of the synthesized pm-CuO NPs were analyzed by UV-Vis, XRD, FT-IR, AFM, SEM, TEM, HR-TEM and EDX. After this, pm-CuO NPs were preliminarily investigated for antibacterial activity on Gram-positive and Gram-negative bacterial strains, and further, their activity was validated for assessing their antibacterial efficiency on the Xanthomonas oryzae, a plant pathogenic bacteria strain, and the obtained results showed that pm-CuO NPs have potency as an effective antibacterial agent for the treatment of the bacterial blight of rice caused by X. oryzae in the rice crop, which reduces the rice crop productivity. Further, pm-CuO NPs were electrophoretically deposited onto an indium–tin–oxide (ITO) glass substrate and assessed for the electro-oxidation of H₂O₂ by cyclic voltammetry (CV), and from this it was proved that pm-CuO NPs had a very high electrochemical sensitivity of 49 μA μM⁻¹ cm⁻² towards H₂O₂ and a low detection limit of 574 μM, with these responses obtained under optimized experimental conditions. Thus, pm-CuO NPs also provide a potential sensing platform for electrochemical studies to detect H₂O₂ produced during plant stress surroundings to properly manage crops susceptible to oxidative damage by elevated H₂O₂ levels during stress.

This study reports plant mediated-copper oxide nanoparticles synthesis from Annona squamosa and their real-life application in agricultural domain for label-free detection of H₂O₂ and its antibacterial efficiency for combating rice crop pathogen.

Sustainable plant and microbes-mediated preparation of Fe3O4 nanoparticles and industrial application of its chitosan, starch, cellulose, and dextrin-based nanocomposites as catalysts

Iron oxide nanoparticles (Fe₃O₄ NPs) attracted significant scientific interest, considering their immense diversity of usage and biocompatibility. Perceiving the growing importance of sustainable chemistry, many efforts have been made to prepare these NPs using naturally occurring materials mostly plant extracts and microbes. Magnetic NPs (MNPs) are commonly used as composites and are considered in two matters: synthesis and modification of their functional groups. Biopolymeric nanocomposites are a group of hybrid materials composed of natural polymers and inorganic nanomaterials. Biopolymers such as alginate, cellulose, starch, gelatin, chitosan, etc. have been considered extensively and provided composites with better electrical and mechanical thermal properties. Fe₃O₄ NPs incorporated in a polymer and biopolymer matrix is a good instance of the functional nanostructure, which has been able to enhance the properties of both ingredients. These hybrids can have impressive applications in various scopes such as magneto-optical storage, electromagnetic interference shielding, catalyst, water remediation, biomedical sensing, and so on. In this study, we have tried to briefly introduce Fe₃O₄ NPs, investigate the green and sustainable methods that have been suggested for its synthesis and review recent utilization of their biopolymeric nanocomposite (NC) including starch, chitosan, dextrin, etc. as catalysts and photocatalysts.

Chitosan/carbon nanotube hybrids: recent progress and achievements for industrial applications

This review focuses on the state-of-the-art of the recent research development on chitosan/CNT nanomaterials in biomedicine, (bio)sensors, and pollution management.

Emerging new-generation hybrids based on covalent organic frameworks for industrial applications

This review highlights the advancement of COF hybrid-based materials for diverse industrial applications.

The latest strategies in the fight against the COVID-19 pandemic: the role of metal and metal oxide nanoparticles

In this review, we summarize and highlight the latest achievements based on nanoparticles in the fight against COVID-19.