Green Synthesis, Characterization and Antimicrobial Activity of Copper Oxide Nanomaterial Derived from Momordica charantia

Unveiling the potency of ZnO and CuO nanocomposites in combating hepatocellular carcinoma by inducing cell death and suppressing migration

Human hepatocellular carcinoma (HCC) is recognized as one of the leading causes of death globally and is resistant to several anticancer drugs. As a result, it is critical to identify more effective druggable therapies. Metal oxide nanoparticles (MO-NPs), especially nanocomposites, have recently received much attention owing to their potential applications in cancer therapy. In this study, we synthesized zinc oxide (ZnO) and copper oxide (CuO) nanocomposites in different ratios (N1, N2, and N3). We evaluated their cytotoxicity against two HCC cell lines (HepG2 and HuH-7) and one normal liver cell (BNL), compared with Sorafenib as a standard therapy. Then, we investigated the potential underlying mechanisms of anticancer action employing flow cytometry, migration assay, and western blot. The results showed that the nanocomposite with an equal ratio of both ZnO and CuO-NPs (N1) exhibited the highest cytotoxic activity on the HuH7 cell line while exerting no detrimental impact on normal rat liver epithelial cells. Further investigation into the toxicity mechanisms of N1 revealed three modalities of induced cell death (apoptotic, necrotic, and autophagic) along with S- and G2/M cell cycle arrest, suggesting mitotic catastrophe. Furthermore, N1 displayed potent anti-migratory activity, surpassing sorafenib, upregulated the protein level of autophagy marker beclin-1, while downregulated the protein level of EMT-marker vimentin. Overall, our findings showed that combining ZnO-NPs and CuO-NPs is more intriguing in combating HCC, providing prospective guidance for evolving liver cancer therapy employing bimetallic NPs.

Characterization and machine learning analysis of hybrid alumina-copper oxide nanoparticles in therminol 55 for medium temperature heat transfer fluid

Efficient heat dissipation is crucial for various industrial and technological applications, ensuring system reliability and performance. Advanced thermal management systems rely on materials with superior thermal conductivity and stability for effective heat transfer. This study investigates the thermal conductivity, viscosity, and stability of hybrid Al2O3-CuO nanoparticles dispersed in Therminol 55, a medium-temperature heat transfer fluid. The nanofluid formulations were prepared with CuO-Al2O3 mass ratios of 10:90, 20:80, and 30:70 and tested at nanoparticle concentrations ranging from 0.1 wt% to 1.0 wt%. Experimental results indicate that the hybrid nanofluids exhibit enhanced thermal conductivity, with a maximum improvement of 32.82% at 1.0 wt% concentration, compared to the base fluid. However, viscosity increases with nanoparticle loading, requiring careful optimization for practical applications. To further analyze and predict thermal conductivity, a Type-2 Fuzzy Neural Network (T2FNN) was employed, demonstrating a correlation coefficient of 96.892%, ensuring high predictive accuracy. The integration of machine learning enables efficient modeling of complex thermal behavior, reducing experimental costs and facilitating optimization. These findings provide insights into the potential application of hybrid nanofluids in solar thermal systems, heat exchangers, and industrial cooling applications.

Biosynthesis of Silver, Copper, and Their Bi-metallic Combination of Nanocomposites by Staphylococcus aureus: Their Antimicrobial, Anticancer Activity, and Cytotoxicity Effect

The present study outlines an easy, cheap, and environmentally friendly way to make Staphylococcus aureus-mediated bimetallic silver-copper nanocomposites (Ag/Cu) that can fight cancer and germs. The gram-positive S. aureus synthesized Ag, Cu, and their bi-metallic nanocomposites extracellularly. We aimed to prepare the bimetallic nanocomposite in two different ways, and we compared them in terms of characterization and biological applications. The first one is a bimetallic nanocomposite (Ag/Cub) that was made by mixing Ag and Cu metal ions in equal amounts (50:50). Then, the whole mixture was reduced. The second is the after-reduction bimetallic nanocomposite (Ag/Cua), in which each metal ion was reduced separately, and then the nanocomposites were mixed (50:50%) during biological applications. Nanocomposites were characterized using UV-visible spectrophotometry, Fourier-transform infrared spectroscopy, dynamic light scattering, and transmission electron microscopy. The results demonstrated that surface plasmon bands were at 320 nm for Ag NPs and 525 nm for Cu NPs, and a shift from these peaks was observed at 290 nm in the Ag/Cub bimetallic nanocomposite. The synthesized nanocomposites were confirmed to be in the nanoscale with 20, 40, and 80 nm spherical crystals, respectively. Nanocomposites were assayed for their antimicrobial activity against the gram-negative Pseudomonas aeruginosa, the acid-fast Mycobacterium smegmatis, the gram-positive Bacillus cereus, and S. aureus, in addition to three fungal species, which were Aspergillus flavus, A. fumigatus, and Candida albicans. The minimum inhibitory concentration and minimum bactericidal concentration were determined. The Ag/Cua/Cuaetallic nanocomposite was the most potent antimicrobial compound. The anticancer activity of the tested compounds was assayed against the hepatocellular carcinoma cell line (HepG-2). Low cytotoxic activity was recorded in most assayed nanocomposites against the baby hamster kidney cell line (BHK).

Supplementary Information

The online version contains supplementary material available at 10.1007/s12088-024-01229-2.

Biogenic Synthesis of Copper Oxide Nanoparticles from Aloe vera: Antibacterial Activity, Molecular Docking, and Photocatalytic Dye Degradation

Green synthesis methods offer a cost-effective and environmentally friendly approach to producing nanoparticles (NPs), particularly metal-based oxides. This study explores the green synthesis of copper oxide nanoparticles using Aloe vera (Aloe barbadensis Miller) leaf extract. The characterization revealed a unique sago-shaped morphology revealed by field-emission scanning electron microscopy and X-ray diffraction analysis. Distinctive metal-oxygen bonds at 521 and 601 cm-1 were confirmed by Fourier-transform infrared (FT-IR) spectroscopy. Furthermore, UV-visible spectroscopy revealed absorbance at 248 nm, suggesting electron transitions across energy bands and varying surface conduction electrons. The band gap value indicated the presence of quantum confinement effects, which were probably caused by the distinctive morphology and surface structure of the biogenic NPs. Additionally, molecular docking studies were carried out against key proteins of Salmonella typhi and Listeria monocytogenes, namely, listeriolysin O (PDB ID: 4CDB), internalin (InlA) (PDB ID: 1O6T), Salmonella effector protein (SopB) (PDB ID: 4DID), and YfdX (PDB ID: 6A07) using AutoDock 4.2. The results revealed binding energies against S. typhi and L. monocytogenes proteins, indicating potential interactions establishing the foundation for further in-depth understanding of the molecular basis underlying the observed antibacterial effects in vitro against S. typhi, Klebsiella pneumoniae, Pseudomonas aeruginosa, and L. monocytogenes. Antibacterial activity evaluation yielded impressive results, with CuO NPs displaying significant activity against S. typhi and L. monocytogenes, exhibiting zones of inhibition values of 13 ± 0.02 and 15 ± 0.04 mm, respectively. Moreover, the CuO NPs demonstrated remarkable photocatalytic efficacy, resulting in the degradation of 77% of the methylene blue dye when exposed to UV irradiation. This study highlighted the potential of green-synthesized CuO NPs derived from A. vera with their unique morphology, interesting spectroscopic properties, and promising antibacterial and photocatalytic activities.

Zinc oxide and copper oxide nanoparticles as a potential solution for controlling Phytophthora infestans, the late blight disease of potatoes

Late blight, caused by Phytophthora infestans, is a major potato disease globally, leading to significant economic losses of $6.7 billion. To address this issue, we evaluated the antifungal activity of ZnO and CuO nanoparticles (NPs) against P. infestans for the first time in laboratory and greenhouse conditions. Nanoparticles were synthesized via a chemical precipitation method and characterized using various techniques. The XRD results revealed that the synthesized ZnO nanoparticles had a pure hexagonal wurtzite crystalline structure, whereas the CuO NPs had a monoclinic crystalline structure. TEM images confirmed the synthesis of quasi-spherical nanoparticles with an average size of 11.5 nm for ZnO NPs and 24.5 nm for CuO NPs. The UV-Vis Spectral Report showed peaks corresponding to ZnO NPs at 364 nm and 252 nm for CuO NPs.In an in vitro study, both ZnO and CuO NPs significantly (p < 0.05) inhibited the radial growth of P. infestans at all tested concentrations compared to the untreated control. The highest inhibitory effect of 100% was observed with ZnO and CuO NPs at 30 mg/L. A lower inhibition of 60.4% was observed with 10 mg/L CuO NPs. Under greenhouse conditions, 100 mg/L ZnO NPs was the most effective treatment for controlling potato late blight, with an efficacy of 71%. CuO NPs at 100 mg/L followed closely, with an efficacy of 69%. Based on these results, ZnO and CuO NPs are recommended as promising eco-friendly fungicides for the management and control of potato late blight after further research.

Enhanced and copper concentration dependent virucidal effect against SARS-CoV-2 of electrospun poly(vinylidene difluoride) filter materials

Virucidal filter materials were prepared by electrospinning a solution of 28 wt % poly(vinylidene difluoride) in N,N-dimethylacetamide without and with the addition of 0.25 wt %, 0.75 wt %, 2.0 wt %, or 3.5 wt % Cu(NO3)2 · 2.5H2O as virucidal agent. The fabricated materials had a uniform and defect free fibrous structure and even distribution of copper nanoclusters. X-ray diffraction analysis showed that during the electrospinning process, Cu(NO3)2 · 2.5H2O changed into Cu2(NO3)(OH)3. Electrospun filter materials obtained by electrospinning were essentially macroporous. Smaller pores of copper nanoclusters containing materials resulted in higher particle filtration than those without copper nanoclusters. Electrospun filter material fabricated with the addition of 2.0 wt % and 3.5 wt % of Cu(NO3)2 · 2.5H2O in a spinning solution showed significant virucidal activity, and there was 2.5 ± 0.35 and 3.2 ± 0.30 logarithmic reduction in the concentration of infectious SARS-CoV-2 within 12 h, respectively. The electrospun filter materials were stable as they retained virucidal activity for three months.

Green Synthesis of Copper and Copper Oxide Nanoparticles From Brown Algae Turbinaria Species' Aqueous Extract and Its Antibacterial Properties

Background Copper and copper oxide nanoparticles synthesized by green methods have attracted considerable attention due to their environmentally friendly properties and potential applications. Green synthesis involves non-hazardous and sustainable techniques used in the production of a wide range of substances, including nanoparticles, pharmaceuticals, and chemicals. These methods often use different organisms, including bacteria, fungi, algae, and plants, each offering different advantages in terms of simplicity, cost-effectiveness, and environmental sustainability. The environmentally friendly nature of these green synthesis methods responds to the growing need for sustainable nanotechnologies. Brown algae have gained popularity due to their distinct morphological characteristics and diverse biochemical composition. This research focuses on the process of synthesizing copper and copper oxide nanoparticles from the brown algae Turbinaria. It emphasizes the natural ability of the bioactive compounds contained in the algae extract to reduce and stabilize the nanoparticles. The green synthesis of copper and copper oxide nanoparticles from brown algae has demonstrated a wide range of applications, including antibacterial activity. Materials and methods Fresh Turbinaria algae were collected from marine environments to ensure that they were free of contaminants. The algae underwent a purification process to remove impurities and were dried. An aqueous extract was prepared by pulverizing the dried algae and mixing them with distilled water. A copper salt solution utilizing copper nitrate was prepared. The algae extract was mixed with the copper salt solution. There are bioactive compounds in the algae extract that help reduce copper ions, which makes copper and copper oxide nanoparticles come together. The reaction mixture was incubated in a controlled environment to facilitate the growth and enhance the stability of the nanoparticles. To separate the nanoparticles from the reaction mixture, centrifugation was employed, or filtration was done with Whatman filter paper (Merck, Burlington, MA). The nanoparticles were dried to yield a stable powder. Results Copper and copper oxide nanoparticles derived from brown algae extract showed antibacterial effects against Streptococcus mutans, Klebsiella sp., and Staphylococcus mutans. The scanning electron microscopy (SEM) analysis verified the irregular shape and elemental content of the synthesized copper and copper oxide nanoparticles. The X-ray diffraction (XRD) analysis indicated that the synthesized nanoparticles exhibited a crystallinity nature and were composed of a mixture of copper and copper oxide species, namely face-centered cubic and monoclinic structures. The transmission electron microscopy (TEM) images showed copper and copper oxide nanoparticles that were evenly distributed and had a rectangular shape. They exhibited substantial antimicrobial activity against both Gram-positive and Gram-negative bacteria. Conclusions This study enhances the field of green synthesis techniques by showcasing the adaptability of Turbinaria brown algae to synthesize copper and copper oxide nanoparticles. It underscores the potential advantages of these nanoparticles in terms of their antibacterial properties.

Green and cost-effective biofabrication of copper oxide nanoparticles: Exploring antimicrobial and anticancer applications

Nanotechnology has made remarkable advancements in recent years, revolutionizing various scientific fields, industries, and research institutions through the utilization of metal and metal oxide nanoparticles. Among these nanoparticles, copper oxide nanoparticles (CuO NPs) have garnered significant attention due to their versatile properties and wide-range applications, particularly, as effective antimicrobial and anticancer agents. CuO NPs can be synthesized using different methods, including physical, chemical, and biological approaches. However, conventional chemical and physical approaches are expensive, resource-intensive, and involve the use of hazardous chemicals, which can pose risks to human health and the environment. In contrast, biological synthesis provides a sustainable and cost-effective alternative by eliminating chemical pollutants and allowing for the production of CuO NPs of tailored sizes and shapes. This comprehensive review focused on the green synthesis of CuO NPs using various biological resources, such as plants, microorganisms, and other biological derivatives. Current knowledge and recent trends in green synthesis methods for CuO NPs are discussed, with a specific emphasis on their biomedical applications, particularly in combating cancer and microbial infections. This review highlights the significant potential of CuO NPs in addressing these diseases. By capitalizing on the advantages of biological synthesis, such as environmental safety and the ability to customize nanoparticle characteristics, CuO NPs have emerged as promising therapeutic agents for a wide range of conditions. This review presents compelling findings, demonstrating the remarkable achievements of biologically synthesized CuO NPs as novel therapeutic agents. Their unique properties and mechanisms enable effective combating against cancer cells and various harmful microbial infections. CuO NPs exhibit potent anticancer activity through diverse mechanisms, including induction of apoptosis, inhibition of angiogenesis, and modulation of signaling pathways. Additionally, their antimicrobial activity manifests through various mechanisms, such as disrupting microbial membranes, generating reactive oxygen species, and interfering with microbial enzymes. This review offers valuable insights into the substantial potential of biologically synthesized CuO NPs as an innovative approach for future therapeutic interventions against cancer and microbial infections.

Nano-based theranostic approaches for infection control: current status and perspectives

Nano-based theranostic platforms constructed from various nanomaterials possess unique advantages in tackling bacterial and fungal infections while detecting pathogenic cells, making them a potential modality for addressing global healthcare burdens.

Evaluation of the in vitro anti-inflammatory and anti-Helicobacter pylori activities of chitosan-based biomaterials modified with copper oxide nanoparticles

For chemical modification, p-aminobenzoic acid was incorporated into chitosan Schiff base (ACsSB) and chitosan (ACs). Two ACs-based CuO nanoparticles composites; ACs/CuONPs-1 % and ACs/CuONPs-5 %, were also synthesized. Their structures were emphasized utilizing several analytical techniques; elemental analysis, FTIR, 1H NMR, XRD, SEM, EDX and TEM. Compared with standard cyclooxygenase (COX) inhibitor, Celecoxib, the prepared biomaterials showed in vitro selective inhibitory effectiveness against COX-2 enzyme that could be sorted, according to their MIC values that produce 50 % inhibition of COX-2 enzyme activity, as follows: Celecoxib (0.28 μg/mL) > ACs/CuONPs-5 % (4.1 μg/mL) > ACs/CuONPs-1 % (14.8 μg/mL) > ACs (38.5 μg/mL) > ACsSB (58.9 μg/mL) > chitosan (>125 μg/mL). Further, ACs/CuONPs-5 % has more in vitro inhibition efficiency towards Helicobacter pylori (H. pylori) than the other prepared biomaterials. Interestingly, the MIC value of 100 % growth inhibition of H. pylori for ACs/CuONP-5 % is equal to that of drug Clarithromycin (1.95 μg/mL). Thus, ACs/CuONPs-5 % has a promising potential as anti-H. pylori and selective anti-inflammatory agent. ACs/CuONPs-5 % is safe on the human gastric normal cells (GES-1). Therefore, amalgamation of both p-aminobenzoic acid and CuONPs into chitosan extremely promoted its anti-inflammatory and anti-H. pylori activity. This is a promising approach to achieve methods successful to compete the conventional antibiotics.

Green adeptness in synthesis of non-toxic copper and cobalt oxide nanocomposites with multifaceted bioactivities

Background

In the present era, we are facing different health problems mainly concerning with drug resistance in microorganisms as well as in cancer cells. In addition, we are also facing the problems of controlling oxidative stress and insect originated diseases like dengue, malaria, chikungunya, etc. originated from mosquitoes. In this investigation, we unfurled the potential of Achatina fulica mucus in green synthesis of mucus mediated copper oxide bio-nanocomposites (SM-CuONC) and cobalt oxide bio-nanocomposites (SM-Co3O4NC). Herein we carried out the physico-chemical characterization like UV–Vis spectra, X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), Transmission electron microscopy (TEM), Energy Dispersive X-ray Analysis (EDAX) and X-ray photoelectron spectroscopy (XPS) of as synthesized bio-nanocomposites. Both the bio-nanocomposites were tested for their potential as antimicrobial activity using well diffusion assay, anticancer activity by MTT assay, antioxidant activity by phosphomolybdenum assay and mosquito larvicidal activity.

Results

The results of this study revealed that, SM-CuONC and SM-Co3O4NC were synthesized successfully using A. fulica mucus. The FESEM and TEM data reveal the formation of nanoparticles with quasi-spherical morphology and average particle size of ~ 18 nm for both nanocomposites. The EDAX peak confirms the presence of elemental copper and cobalt in the analyzed samples. The X-ray diffraction analysis confirmed the crystalline nature of the CuO and Co3O4. The result of anti microbial study exhibited that, SM-CuONC showed maximum antimicrobial activity against Escherichia coli NCIM 2065 and Aspergillus fumigatus NCIM 902 which were noted as 2.36 ± 0.31 and 2.36 ± 0.59 cm resp. at 60 µg/well concentration. The result of anticancer activity for SM-CuONC was exhibited as, 68.66 ± 3.72, 62.66 ± 3.61 and 71.00 ± 2.36 percent kill, while SM-Co3O4NC exhibited 61.00 ± 3.57, 72.66 ± 4.50 and 71.66 ± 4.22 percent kill against Human colon cancer (HCT-15), Cervical cancer (HeLa), and Breast cancer (MDA-MB-231) cell lines, respectively, at 20 µg/well concentration. Both the nanocomposites also exhibited better antioxidant activity. Total antioxidant activity for SM-CuONC at 50 µg/ml concentration was found to be highest as 55.33 ± 3.72 while that of SM-Co3O4Ns was 52.00 ± 3.22 mM of ascorbic acid/µg respectively. Both bio-nanocomposites also exhibited 100% mosquito larvicidal activity at concentration ranging from 40 to 50 mg/l. During cytotoxicity study it is noted that at 5 µg/well concentration, SM-CuO and SM-Co3O4NCs suspension showed more than 97% viability of normal (L929) cell lines. We also studied phytotoxicity of both bio-nanocomposites on Triticum aestivum. In this study, 100% seed germination was observed when seeds are treated with SM-CuONC and SM-Co3O4NC at 500 mg/l and 250 mg/l concentration respectively.

Conclusions

This study concludes that in future as synthesized SM-CuONC and SM-Co3O4NC can be used in pharmaceutical, health care system for betterment and welfare of human life as both bio-nanocomposites exhibits better antimicrobial, anticancer, antioxidant and mosquito larvicidal potential.

Green synthetized Cu-Oxide Nanoparticles: Properties and applications for enhancing healing of wounds infected with Staphylococcus aureus

Treating wound infections is a challenging concern in various clinical settings in Egypt, especially in the increasing global problem of resistance to antimicrobials. Here, we aimed to fabricate CuO NPs via green synthesis using aqueous Yucca gigantea extract. Then, the effect of green synthesized CuO NPs on Staphylococcus aureus clinical isolates has been studied in vivo and in vitro. The aqueous extract of Yucca gigantea has been employed in our study as a scale-up approach to safely, affordably, sustainably, and practically fabricate copper oxide nanoparticles (CuO NPs). Fourier transforms infrared (FT-IR), X-ray Diffraction (XRD), and UV-vis spectroscopy were utilized in vitro to describe the bonding features of CuO NPs.Scanning Electron microscopy (SEM), Transmission electron microscopy (TEM), Energy dispersive X-ray (EDX), and dynamic light scattering (DLS) were used to detect the morphological and elemental composition of the resulting CuO NPs. The fabrication of CuO NPs was confirmed by the IR spectral band at 515 cm-1, ensuring the metal-oxygen bondCu-O with two strong bands at 229 and 305 nm. SEM and TEM show CuO NPs with a size range from 30 to 50 nm. Cu and O comprised most of the particles produced through green synthesis, with weight percentages of 57.82 and 42.18 %, respectively. CuO NPs were observed to have a Zeta-potential value of -15.7 mV, demonstrating their great stability. CuO NPs revealed antibacterial potential toward the tested isolates with minimum inhibitory concentration values of 128 to 512 µg/mL. CuO NPs had antibiofilm potential by crystal violet assay, downregulating the expression of icaA and icaD genes in 23.07 % and 19.32 of the S. aureus isolates. The wound-healing potential of CuO NPs was investigated in vivo. It significantly decreased the bacterial burden and increased wound healing percentage compared to the positive control group. Moreover, CuO NPs caused an upregulation of the genes encoding platelet-derived growth factor (PDGF) and fibronectin in tissue repair. Thus, we can use CuO NPs as a future source for wound healing materials, especially in infected wounds.

Facile synthesis of CuONPs using Citrus limon juice for enhancing antibacterial activity against methicillin-resistant Staphylococcus aureus, beta-lactamase and tetracycline-resistant Escherichia coli

Antimicrobial resistance (AMR) resulting from indiscriminate use of antibiotics in various fields of agriculture such as livestock farming, aquaculture, and croup fields become an emerging catatroph for the health (human, animal) and environment. Among those, poultry farming has been considered as one of the major contributors of multidrug-resistant (MDR) bacteria. Focusing this, the present research is designed for green synthesis of copper oxide nanoparticles (CuONPs) with the aim of their application in antibiotic-free poultry farming for curving use of antibiotics in that sector. For that, antibacterial CuONPs were nanoformulated to decrease the required doses of bulk CuSO4. We used a CuSO4·5H2O solution as a Cu2+ source and Citrus limon juice as a reducing agent as well as capping agent. Particle yield was initially confirmed by the λmax specific to CuONPs (295 nm) using UV-Vis spectroscopy. The presence of the Cu-O group during particle formation and crystallinity with the purity of yielded NPs was confirmed with Fourier-transform infrared spectroscopy and X-ray diffractometry. The round to spherical CuONPs of 92-155 nm average size was confirmed with atomic force, scanning electron, and transmission electron microscopy. The concentration of yielded NPs was calculated with the dynamic light scattering. The physical characterization tools indicated a maximum CuONPs yield with a 0.001 M ion source with 15% reducing agents after 12 h reduction. Antibacterial effectivity was tested against methicillin-resistant Staphylococcus aureus and tetracycline- and beta-lactamase-resistant Escherichia coli, confirmed by PCR amplicon band at 163 bp, 643 bp, and 577 bp for the mecA, blaTEM-1 and tetA genes, respectively. An antibiogram assay of CuONPs showed a maximum zone of inhibition of 26 ± 0.5 mm for the synthesized particles. The minimum inhibitory and bactericidal concentrations were 1.6 μg ml-1 and 3.1 μg ml-1, respectively, for broad-spectrum application. Finally, the biocompatibility of CuONPs was determined by demonstrating a nonsignificant decrease of BHK-21 cell viability at <2 MIC doses for complying their future in vivo applicability.

Copper and Copper-Based Nanoparticles in Medicine-Perspectives and Challenges

Nanotechnology has ushered in a new era of medical innovation, offering unique solutions to longstanding healthcare challenges. Among nanomaterials, copper and copper oxide nanoparticles stand out as promising candidates for a multitude of medical applications. This article aims to provide contemporary insights into the perspectives and challenges regarding the use of copper and copper oxide nanoparticles in medicine. It summarises the biomedical potential of copper-based nanoformulations, including the progress of early-stage research, to evaluate and mitigate the potential toxicity of copper nanomaterials. The discussion covers the challenges and prospects of copper-based nanomaterials in the context of their successful clinical translation. The article also addresses safety concerns, emphasizing the need for toxicity assessments of nanomedicines. However, attention is needed to solve the current challenges such as biocompatibility and controlled release. Ongoing research and collaborative efforts to overcome these obstacles are discussed. This analysis aims to provide guidance for the safe and effective integration of copper nanoparticles into clinical practice, thereby advancing their medical applications. This analysis of recent literature has highlighted the multifaceted challenges and prospects associated with copper-based nanomaterials in the context of their translation from the laboratory to the clinic. In particular, biocompatibility remains a formidable hurdle, requiring innovative solutions to ensure the seamless integration into the human body. Additionally, achieving the controlled release of therapeutic agents from copper nanoparticles poses a complex challenge that requires meticulous engineering and precise design.

Fabrication of chitosan and Trianthema portulacastrum mediated copper oxide nanoparticles: Antimicrobial potential against MDR bacteria and biological efficacy for antioxidant, antidiabetic and photocatalytic activities

Biopolymer based metal oxide nanoparticles, prepared by eco-friendly approach, are gaining interest owing to their wide range of applications. In this study, aqueous extract of Trianthema portulacastrum was used for the green synthesis of chitosan base copper oxide (CH-CuO) nanoparticles. The nanoparticles were characterized through UV-Vis Spectrophotometry, SEM, TEM, FTIR and XRD analysis. These techniques provided evidence for the successful synthesis of the nanoparticles, having poly-dispersed spherical shaped morphology with average crystallite size of 17.37 nm. The antibacterial activity for the CH-CuO nanoparticles was determined against multi-drug resistant (MDR), Escherichia coli, Pseudomonas aeruginosa (gram-negative), Enterococcus faecium and Staphylococcus aureus (gram-positive). Maximum activity was obtained against Escherichia coli (24 ± 1.99 mm) while least activity was observed against Staphylococcus aureus (17 ± 1.54 mm). In-vitro analysis for biofilm inhibition, EPS and cell surface hydrophobicity showed >60 % inhibitions for all the bacterial isolates. Antioxidant and photocatalytic assays for the nanoparticles showed significant activities of radical scavenging (81 ± 4.32 %) and dye degradation (88 %), respectively. Antidiabetic activity for the nanoparticles, determined by in-vitro analysis of alpha amylase inhibition, showed enzyme inhibition of 47 ± 3.29 %. The study signifies the potential of CH-CuO nanoparticle as an effective antimicrobial agent against MDR bacteria along with the antidiabetic and photocatalytic activities.

Toxicological assessment of Phormidium sp. derived copper oxide nanoparticles for its biomedical and environmental applications

Driven by the need to biosynthesized alternate biomedical agents to prevent and treat infection, copper oxide nanoparticles (CuONPs) have surfaced as a promising avenue. Cyanobacteria-derived synthesis of CuONPs is of substantive interest as it offers an eco-friendly, cost-effective, and biocompatible route. In the present study biosynthesized CuONPs were characterized and investigated regarding their toxicity. Morphological analysis using TEM, SEM and AFM showed the spherical particle size of 20.7 nm with 96% copper that confirmed the purity of CuONPs. Biogenic CuONPs with IC₅₀ value of 64.6 µg ml^-1 showed 90% scavenging of free radicals in superoxide radical scavenging assay. CuONPs showed enhanced anti-inflammatory activity by 86% of protein denaturation with IC₅₀ value of 89.9 µg ml^-1. Biogenic CuONPs exhibited significant toxicity against bacterial strains with lowest MIC value of 62.5 µg ml^-1 for B. cereus and fungal strain with a MIC value of 125 µg ml^-1 for C. albicans. In addition CuONPs demonstrated a high degree of synergistic interaction when combined with standard drugs. CuONPs exhibited significant cytotoxicity against non-small cell lung cancer with an IC₅₀ value of 100.8 µg ml^-1 for A549 and 88.3 µg ml^-1 for the H1299 cell line with apoptotic activities. Furthermore, biogenic CuONPs was evaluated for their photocatalytic degradation potential against methylene blue dye and were able to removed 94% dye in 90 min. Free radical scavenging analysis suggested that CuONPs assisted dye degradation was mainly induced by hydroxide radicals. Biogenic CuONPs appears as an eco-friendly and cost effective photocatalyst for the treatment of wastewater contaminated with synthetic dyes that poses threat to aquatic biota and human health. The present study highlighted the blend of biomedical and photocatalytic potential of Phormidium derived CuONPs as an attractive approach for future applications in nanomedicine and bioremediation.

Concurrent Tissue Engineering for Wound Healing in Diabetic Rats Utilizing Dual Actions of Green Synthesized CuO NPs Prepared from Two Plants Grown in Egypt

Purpose

Diabetes mellitus is among the disrupting factors of orchestrated events in wound healing. This necessitates the urge for tailored medications, which are continually offered by nano-sized materials. Herein, we present greenly synthesized copper oxide nanoparticles (CuO NPs), obtained from either Punica granatum L. (PG) or Pisidium guajava L. (GV) extract, to function as potent bactericidal and fungicidal materials that promote regeneration and healing of the targeted diabetic wounded tissues.

Methods

PG or GV plant extracts were compared as source of reducing agents for CuO NPs synthesis process. The yield and photocatalytic degradation potential were compared. NPs obtained from the superior extract, PG, were characterized using particles size, zeta potential, XRD, TEM, SEM, and EDX. The antimicrobial effects were evaluated on multidrug-resistant human pathogens and then the percentage biofilm inhibitory concentration was determined. The cytotoxicity and wound scratch study were conducted on a normal human skin cell line. In-vivo wound healing activity in diabetic rats was assessed along with histopathological and immunohistochemical examination of CD45 and α-SMA.

Results

The greenly synthesized CuO NPs are spherical in shape having a diameter of 233nm. CuO NPs (250µg/mL) acted as promising biocontrol agent against a variety of multidrug-resistant human pathogens. They significantly exhibited 29.460±0.811% healing of the scratched wound compared to only 2.001±0.155% for the control. Wound healing experiments revealed the safety of a low CuO NPs concentration in a diabetic animal model as well as on human normal skin fibroblast cell line. The treated group with a dose of 2mg/cm2 showed superior results with a WC50 value of 7.2 days, and 92% wound contraction after 13-days. Immunohistochemical investigation of the same group demonstrated well-established fibrous tissue (5.7±3.7/HPF), and an amplified granulation tissue of recently developed blood vessels (70±1.5/HPF).

Conclusion

Green synthesized CuO NPs could overcome drug resistance and promote wound healing process effectively.

Green synthesis and antimicrobial mechanism of nanoparticles: applications in agricultural and agrifood safety

The growing demand for food and its safety are a challenge for agriculture and agrifood. This has led to the incorporation of alternatives such as organic agriculture, the use of biocontrollers, the development of transgenic plants resistant to pathogens and the incorporation of nanotechnology. In this sense, agrochemicals based on nanoparticles (NPs) have been developed. Recently, the green synthesis of NPs has grown rapidly and, for this reason, molecules, microorganisms, fungi and plants are used. Synthesis from plant extracts offers a broad spectrum and, despite the fact that NPs are usually dispersed in size and shape, extensive antimicrobial effectiveness has been demonstrated at nanomolar concentrations. It has been shown that the mechanism of action can be through the dissipation of the driving force of the protons, the alteration of cellular permeability, the formation of bonds with the thiol group of the proteins, the generation of reactive species of oxygen, and the hyperoxidation of DNA, RNA and even the cell membrane. To improve the efficiency of NPs, modifications have been made such as coating with other metals, the addition of antibiotics, detergents and surfactants, as well as the acidification of the solution. Consequently, NPs are considered as a promising method for achieving safety in the agricultural and agrifood area. However, it is necessary to investigate the side effects of NPs, when applied in agroecological systems, on the textural, nutriment and sensory properties of food, as well as the impact on human health. © 2022 Society of Chemical Industry.

Phytochemical-Based Nanomaterials against Antibiotic-Resistant Bacteria: An Updated Review

Antibiotic-resistant bacteria (ARB) is a growing global health threat, leading to the search for alternative strategies to combat bacterial infections. Phytochemicals, which are naturally occurring compounds found in plants, have shown potential as antimicrobial agents; however, therapy with these agents has certain limitations. The use of nanotechnology combined with antibacterial phytochemicals could help achieve greater antibacterial capacity against ARB by providing improved mechanical, physicochemical, biopharmaceutical, bioavailability, morphological or release properties. This review aims to provide an updated overview of the current state of research on the use of phytochemical-based nanomaterials for the treatment against ARB, with a special focus on polymeric nanofibers and nanoparticles. The review discusses the various types of phytochemicals that have been incorporated into different nanomaterials, the methods used to synthesize these materials, and the results of studies evaluating their antimicrobial activity. The challenges and limitations of using phytochemical-based nanomaterials, as well as future directions for research in this field, are also considered here. Overall, this review highlights the potential of phytochemical-based nanomaterials as a promising strategy for the treatment against ARB, but also stresses the need for further studies to fully understand their mechanisms of action and optimize their use in clinical settings.

Novel Microwave Synthesis of Copper Oxide Nanoparticles and Appraisal of the Antibacterial Application

The exceptional characteristics of bio-synthesized copper oxide nanoparticles (CuO NPs), including high surface-to-volume ratio and high-profit strength, are of tremendous interest. CuO NPs have cytotoxic, catalytic, antibacterial, and antioxidant properties. Fruit peel extract has been recommended as a valuable alternative method due to the advantages of economic prospects, environment-friendliness, improved biocompatibility, and high biological activities, such as antioxidant and antimicrobial activities, as many physical and chemical methods have been applied to synthesize metal oxide NPs. In the presence of apple peel extract and microwave (MW) irradiation, CuO NPs are produced from the precursor CuCl₂. 2H₂O. With the help of TEM analysis, and BET surface area, the average sizes of the obtained NPs are found to be 25-40 nm. For use in antimicrobial applications, CuO NPs are appropriate. Disk diffusion tests were used to study the bactericidal impact in relation to the diameter of the inhibition zone, and an intriguing antibacterial activity was confirmed on both the Gram-positive bacterial pathogen Staphylococcus aureus and Gram-negative bacterial pathogen Escherichia coli. Moreover, CuO NPs did not have any toxic effect on seed germination. Thus, this study provides an environmentally friendly material and provides a variety of advantages for biomedical applications and environmental applications.

Hybrid Nanosystems of Antibiotics with Metal Nanoparticles-Novel Antibacterial Agents

The appearance and increasing number of microorganisms resistant to the action of antibiotics is one of the global problems of the 21st century. Already, the duration of therapeutic treatment and mortality from infectious diseases caused by pathogenic microorganisms have increased significantly over the last few decades. Nanoscale inorganic materials (metals and metal oxides) with antimicrobial potential are a promising solution to this problem. Here we discuss possible mechanisms of pathogenic microorganisms' resistance to antibiotics, proposed mechanisms of action of inorganic nanoparticles on bacterial cells, and the possibilities and benefits of their combined use with antibacterial drugs. The prospects of using metal and metal oxide nanoparticles as carriers in targeted delivery systems for antibacterial compositions are also discussed.

Bacteria assisted green synthesis of copper oxide nanoparticles and their potential applications as antimicrobial agents and plant growth stimulants

Copper oxide nanoparticles (CuO-NPs) have piqued the interest of agricultural researchers due to their potential application as fungicides, insecticides, and fertilizers. The Serratia sp. ZTB29 strain, which has the NCBI accession number MK773873, was a novel isolate used in this investigation that produced CuO-NPs. This strain can survive concentrations of copper as high as 22.5 mM and can also remove copper by synthesizing pure CuO-NPs. UV-VIS spectroscopy, DLS, Zeta potential, FTIR, TEM, and XRD techniques were used to investigate the pure form of CuO-NPs. The synthesized CuO-NPs were crystalline in nature (average size of 22 nm) with a monoclinic phase according to the XRD pattern. CuO-NPs were found to be polydisperse, spherical, and agglomeration-free. According to TEM and DLS inspection, they ranged in size from 20 to 40 nm, with a typical particle size of 28 nm. CuO-NPs were extremely stable, as demonstrated by their zeta potential of -15.4 mV. The ester (C=O), carboxyl (C=O), amine (NH), thiol (S-H), hydroxyl (OH), alkyne (C-H), and aromatic amine (C-N) groups from bacterial secretion were primarily responsible for reduction and stabilization of CuO-NPs revealed in an FTIR analysis. CuO-NPs at concentrations of 50 μg mL^-1 and 200 μg mL^-1 displayed antibacterial and antifungal activity against the plant pathogenic bacteria Xanthomonas sp. and pathogenic fungus Alternaria sp., respectively. The results of this investigation support the claims that CuO-NPs can be used as an efficient antimicrobial agent and nano-fertilizer, since, compared to the control and higher concentrations of CuO-NPs (100 mg L^-1) considerably improved the growth characteristics of maize plants.

The anti SARS-CoV-2 activity of nanofibrous filter materials activated with metal clusters

Nanofibrous filter materials were prepared by electrospinning a solution of 28 wt% poly(vinylidene fluoride) in N,N-dimethylacetamide with and without the addition of 2 wt% AgNO₃, Cu(NO₃)₂·2.5H₂O or ZnCl₂. X-ray diffraction, scanning electron microscopy with energy dispersive X-ray spectroscopy, inductively coupled plasma mass spectroscopy, thermogravimetric analysis, contact angle measurement, nitrogen sorption, and mercury intrusion porosimetry methods were used for the characterization of physical structure as well as the chemical composition of the electrospun materials. Particle filtration efficiency and antiviral activity against the SARS-CoV-2 alpha variant were tested in order to estimate the suitability of the prepared electrospun filter materials for application as indoor air filtration systems with virucidal properties. All filter materials prepared with salts demonstrated very high particle filtration efficiency (≥98.0%). The best antiviral activity was demonstrated by a material containing Cu(NO₃)₂·2.5H₂O in the spinning solution, which displayed the decrease in the number of infectious virions by three orders of magnitude after a contact time of 12 h. Materials with the addition of AgNO₃ and ZnCl₂ decreased the number of infectious virions after the same contact time by only ∼8 and ∼11 times, respectively.

One Pot Synthesis of Copper Oxide Nanoparticles for Efficient Antibacterial Activity

The unique semiconductor and optical properties of copper oxides have attracted researchers for decades. However, using fruit waste materials such as peels to synthesize the nanoparticles of copper oxide (CuO NPs) has been rarely described in literature reviews. The main purpose of this part of the research was to report on the CuO NPs with the help of apple peel extract under microwave irradiation. Metal salts and extracts were irradiated at 540 W for 5 min in a microwave in a 1:2 ratio. The crystallinity of the NPs was confirmed by the XRD patterns and the crystallite size of the NPs was found to be 41.6 nm. Elemental mapping of NPs showed homogeneous distributions of Cu and O. The NPs were found to contain Cu and O by EDX and XPS analysis. In a test involving two human pathogenic microbes, NPs showed antibacterial activity and the results revealed that the zone of inhibition grew significantly with respect to the concentration of CuO NPs. In a biofilm, more specifically, NPs at 25.0 µg/mL reduced mean thickness and biomass values of S. aureus and E. coli biofilms by >85.0 and 65.0%, respectively, with respect to untreated controls. In addition, environmentally benign materials offer a number of benefits for pharmaceuticals and other biomedical applications as they are eco-friendly and compatible.

Effect of the green synthesis of CuO plate-like nanoparticles on their photodegradation and antibacterial activities

Green synthesis of copper oxide nanoparticles and its effects on photocatalytic dye degradation and antibacterial activities are reported. The synthesis of nanoparticles by green routes provides many advantages over chemical routes, including simplicity, cost-effectiveness, and fast processing route without using any costly or harmful chemicals. Tridax procumbense (coat buttons) plant root extract was used to synthesize copper oxide nanoparticles. The synthesized Tridax procumbense-copper oxide nanoparticles (TP-CuO NPs) were characterized by UV-visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), dynamic light scattering spectroscopy (DLS), and X-ray diffraction (XRD) techniques. The synthesized TP-CuO NPs were applied for photocatalytic dye degradation and antibacterial activity studies. The TP-CuO NPs exhibited a maximum antibacterial activity at 500 μg mL^-1 concentration against Staphylococcus aureus and E. coli showing inhibition zones of 7.5 mm and 7.2 mm, respectively. The photocatalytic ability of the TP-CuO was also tested against the textile dye Trypan blue (TB), and showed about 55% degradation after 48 h for 500 μg mL^-1 CuO NP concentration, showing a concentration-dependent degradation efficiency. This is the first work on TP-derived CuO nanoparticles and their photocatalytic and antimicrobial applications. Overall, this study supports the superiority of green-synthesized TP-CuO NPs as photocatalytic and antimicrobial agents.

The mechanism of metal-based antibacterial materials and the progress of food packaging applications: A review

Food packages have been detected carrying novel coronavirus in multi-locations since the outbreak of COVID-19, causing major concern in the field of food safety. Metal-based supported materials are widely used for sterilization due to their excellent antibacterial properties as well as low biological resistance. As the principal part of antibacterial materials, the active component, commonly referred to Ag, Cu, Zn, etc., plays the main role in inhibiting and killing pathogenic microorganisms by destroying the structure of cells. As another composition of metal-based antibacterial materials, the carrier could support and disperse the active component, which on one hand, could effectively decrease the usage amount of active component, on the other hand, could be processed into various forms to broaden the application range of antibacterial materials. Different from other metal-based antibacterial reviews, in order to highlight the detailed function of various carriers, we divided the carriers into biocompatible and adsorptable types and discussed their different antibacterial effects. Moreover, a novel substitution antibacterial mechanism was proposed. The coating and shaping techniques of metal-based antibacterial materials as well as their applications in food storage at ambient and low temperatures are also comprehensively summarized. This review aims to provide a theoretical basis and reference for researchers in this field to develop new metal-based antibacterial materials.

Nano-microbial based technology employing polyvalent phage conjugate: A next generation weapon for antimicrobial resistance lurking behind wastewater

Worldwide, due to a dearth of innovative interventions, new forms of antimicrobial resistance (AMR) are being discovered every day in clinical and environmental settings. Therefore, it is necessary to remove these contaminants directly or indirectly from the environment. Nanomicrobial-based technology employing nanomaterials with microbes is a new paradigm that finds a place in the antimicrobial crisis. Microbial entities such as phages can be used to treat antimicrobial resistance, but phage resistance is challenging and limits its applicability. Similarly, nanotechnology will not be able to selectively remove resistant strains from the environment individually. Therefore, we employ nanomicrobial-based technology that aims to fill these gaps. In the present study, polyvalent phages were isolated from wastewater with an easy-to-use modified multi-host sequential approach, characterized and conjugated with magnetite (Fe₃O₄) nanoparticles with the modified formulation to form nanomicrobial conjugates (NMCs). These NMCs were subjected to characterization and in vitro antibacterial studies. The results indicated a significant polyvalency of phages in the order of Caudovirales. Transmission electron microscopy (TEM) analysis of Fe₃O₄ nanoparticles formed by the co-precipitation method showed a particle size of 30 ± 5 nm and the selected area electron diffraction (SAED) pattern indicates a single-phase crystalline structure. To form NMCs, isolated phages (10⁵ PFU/mL) were immobilized onto Fe₃O₄ nanoparticles. Further, surface modification of Fe₃O₄ nanoparticles enables the covalent association of phages. Biosurfactant-functionalized Fe₃O₄ nanoparticles (FNMCs) were found to have higher phage loading capacity, with a significant value of p < 0.0127 and a zeta potential of -22.2 mV. TEM studies and in vitro biofilm assay showed that NMCs exhibit promising antibacterial activity against various resistant bacterial strains. Pilot studies showed that NMCs can selectively eliminate up to 98.3% of AMR in wastewater. Thus, these findings indicate a synergistic effect of both phage and nanomaterial and this technology is expected to be a new lead in wastewater management.

Comparison of In Vitro Approaches to Assess the Antibacterial Effects of Nanomaterials

The antibacterial properties of nanomaterials (NMs) can be exploited in a range of consumer products (e.g., wound dressings, food packaging, textiles, medicines). There is also interest in the exploitation of NMs as treatments for infectious diseases to help combat antibiotic resistance. Whilst the antibacterial activity of NMs has been assessed in vitro and in vivo in numerous studies, the methodology used is very varied. Indeed, while numerous approaches are available to assess the antibacterial effect of NMs in vitro, they have not yet been systematically assessed for their suitability and sensitivity for testing NMs. It is therefore timely to consider what assays should be prioritised to screen the antibacterial properties of NMs. The majority of existing in vitro studies have focused on investigating the antibacterial effects exhibited by silver (Ag) NMs and have employed a limited range of assays. We therefore compared the antibacterial effects of copper oxide (CuO) NMs to Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis at various concentrations (12.5-200 µg/mL) using a battery of tests (well and disc diffusion, plate counts-time-kill method, optical density measurement-OD, Alamar Blue and live/dead viability assays, and quantitative polymerase chain reaction). CuO NMs were most toxic to B. subtilis and E. coli, while P. aeruginosa was the least sensitive strain. All assays employed detected the antibacterial activity of CuO NMs; however, they varied in their sensitivity, time, cost, technical difficulty and requirement for specialized equipment. In the future, we suggest that a combination of approaches is used to provide a robust assessment of the antibacterial activity of NMs. In particular, we recommend that the time-kill and OD assays are prioritised due to their greater sensitivity. We also suggest that standard operating protocols are developed so that the antibacterial activity of NMs can be assessed using a harmonised approach.

Autophagy and lipid droplets are a defense mechanism against toxic copper oxide nanotubes in the eukaryotic microbial model Tetrahymena thermophila

The widespread use of inorganic nanomaterials of anthropogenic origin has significantly increased in the last decade, being now considered as emerging pollutants. This makes it necessary to carry out studies to further understand their toxicity and interactions with cells. In the present work we analyzed the toxicity of CuO nanotubes (CuONT) in the ciliate Tetrahymena thermophila, a eukaryotic unicellular model with animal biology. CuONT exposure rapidly induced ROS generation in the cell leading to oxidative stress and upregulation of genes encoding antioxidant enzymes (catalase, superoxide dismutase, glutathione peroxidase), metal-chelating metallothioneins and cytochrome P450 monooxygenases. Comet assays and overexpression of genes involved in DNA repair confirmed oxidative DNA damage in CuONT-treated cells. Remarkably, both electron and fluorescent microscopy revealed numerous lipid droplets and autophagosomes containing CuONT aggregates and damaged mitochondria, indicating activation of macroautophagy, which was further confirmed by a dramatic upregulation of ATG (AuTophaGy related) genes. Treatment with autophagy inhibitors significantly increased CuONT toxicity, evidencing the protective role of autophagy towards CuONT-induced damage. Moreover, increased formation of lipid droplets appears as an additional mechanism of CuONT detoxification. Based on these results, we present a hypothetical scenario summarizing how T. thermophila responds to CuONT toxicity. This study corroborates the use of this ciliate as an excellent eukaryotic microbial model for analyzing the cellular response to stress caused by toxic metal nanoparticles.

Combination Strategies of Different Antimicrobials: An Efficient and Alternative Tool for Pathogen Inactivation

Despite the discovery and development of an array of antimicrobial agents, multidrug resistance poses a major threat to public health and progressively increases mortality. Recently, several studies have focused on developing promising solutions to overcome these problems. This has led to the development of effective alternative methods of controlling antibiotic-resistant pathogens. The use of antimicrobial agents in combination can produce synergistic effects if each drug invades a different target or signaling pathway with a different mechanism of action. Therefore, drug combinations can achieve a higher probability and selectivity of therapeutic responses than single drugs. In this systematic review, we discuss the combined effects of different antimicrobial agents, such as plant extracts, essential oils, and nanomaterials. Furthermore, we review their synergistic interactions and antimicrobial activities with the mechanism of action, toxicity, and future directions of different antimicrobial agents in combination. Upon combination at an optimum synergistic ratio, two or more drugs can have a significantly enhanced therapeutic effect at lower concentrations. Hence, using drug combinations could be a new, simple, and effective alternative to solve the problem of antibiotic resistance and reduce susceptibility.

Recent Advances in Copper and Copper-Derived Materials for Antimicrobial Resistance and Infection Control

Antibacterial properties of copper have been known for ages. With the rise of antimicrobial resistance (AMR), hospital-acquired infections, and the current SARS-CoV-2 pandemic, copper and copper-derived materials are being widely researched for healthcare ranging from therapeutics to advanced wound dressing to medical devices. We cover current research that highlights the potential uses of metallic and ionic copper, copper alloys, copper nanostructures, and copper composites as antibacterial, antifungal, and antiviral agents, including those against the SARS-CoV-2 virus. The applications of copper-enabled engineered materials in medical devices, wound dressings, personal protective equipment, and self-cleaning surfaces are discussed. We emphasize the potential of copper and copper-derived materials in combating AMR and efficiently reducing infections in clinical settings.

Nanoparticles of Bioactive Metals/Metal Oxides and Their Nanocomposites with Antibacterial Drugs for Biomedical Applications

The increasing appearance of new strains of microorganisms resistant to the action of existing antibiotics is a modern problem that requires urgent decision. A promising potential solution is the use of nanoparticles of bioactive metals and their oxides as new antibacterial agents, since they are capable of affecting pathogenic microorganisms by mechanisms different from the mechanisms of action of antibiotics. Inorganic nanoparticles possess a wide spectrum of antibacterial activity. These particles can be easily conjugated with drug molecules and become carriers in targeted drug-delivery systems. This paper discusses the benefits and prospects of the application of nanoparticles from metals and metal oxides and their nanocomposites with antibacterial drugs.

Biogenic Synthesis and Characterization of Chitosan-CuO Nanocomposite and Evaluation of Antibacterial Activity against Gram-Positive and -Negative Bacteria

Chitosan-copper oxide (CHT-CuO) nanocomposite was synthesized using olive leaf extract (OLE) as reducing agent and CuSO4⋅5H2O as precursor. CHT-CuO nanocomposite was prepared using an in situ method in which OLE was added to a solution of chitosan and CuSO4⋅5H2O mixture in the ratio of 1:5 (v/v) and heated at a temperature of 90 °C. The obtained CHT-CuO nanocomposite was characterized using field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), ultraviolet-visible (UV-Vis) spectrophotometry, energy-dispersive X-ray spectroscopy (EDAX), Fourier transform infrared spectroscopy (FTIR), and high-resolution transmission electron microscopy (TEM). TEM results indicated that CHT-CuO nanocomposite are spherical in shape with size ranging from 3.5 to 6.0 nm. Antibacterial activity of the synthesized nanocomposites was evaluated against Gram-positive (Bacillus cereus, Staphyloccous haemolytica and Micrococcus Luteus) and Gram-negative (Escherichia coli, Pseudomonas citronellolis, Pseudomonas aeruginosa, kliebisella sp., Bradyrhizobium japonicum and Ralstonia pickettii) species by cup platting or disc diffusion method. Overall, against all tested bacterial strains, the diameters of the inhibition zone of the three nanocomposites fell between 6 and 24 mm, and the order of the antimicrobial activity was as follows: CuO-1.0 > CuO-0.5 > CuO-2.0. The reference antibiotic amoxicillin and ciprofloxacin showed greater activity based on the diameter of zones of inhibition (between 15−32 mm) except for S. heamolytica and P. citronellolis bacteria strains. The nanocomposites MIC/MBC were between 0.1 and 0.01% against all tested bacteria, except S. heamolityca (>0.1%). Based on MIC/MBC values, CuO-0.5 and CuO-1.0 were more active than CuO-2.0, in line with the observations from the disc diffusion experiment. The findings indicate that these nanocomposites are efficacious against bacteria; however, Gram-positive bacteria were less susceptible. The synthesized CHT-CuO nanocomposite shows promising antimicrobial activities and could be utilized as an antibacterial agent in packaging and medical applications.

Phyto-Mediated Copper Oxide Nanoparticles for Antibacterial, Antioxidant and Photocatalytic Performances

The greatest challenge of the current generation and generations to come is antimicrobial resistance, as different pathogenic bacteria have continuously evolved to become resistant to even the most recently synthesized antibiotics such as carbapenems. Resistance to carbapenems limits the therapeutic options of MDR infections as they are the only safe and effective drugs recommended to treat such infections. This scenario has complicated treatment outcomes, even to the commonest bacterial infections. Repeated attempts to develop other approaches have been made. The most promising novel therapeutic option is the use of nanomaterials as antimicrobial agents. Thus, this study examined the efficacy of Camellia sinensis extract (CSE) and Prunus africana bark extract (PAE) green synthesized Copper oxide nanoparticles (CuONPs) against carbapenem-resistant bacteria. Furthermore, the photocatalytic and antioxidant activities of CuONPs were evaluated to determine the potential of using them in a wide range of applications. CuONPs were biosynthesized by CSE and PAE. UV vis spectroscopy, X-ray Diffraction (XRD), Dynamic light scattering (DLS), Fourier Transform Infrared spectroscopy (FTIR), and Scanning Electron Microscopy (SEM) were used to characterize the nanoparticles. CuONPs susceptibility tests were carried out by the agar well diffusion method. The photocatalytic and antioxidant activities of the CuONPs were determined by the methylene blue and DPPH free radical scavenging assays, respectively. UV vis absorbance spectra registered surface plasmon resonance peaks between 272 and 286 nm, confirming the presence of CuONPs. The XRD array had nine strong peaks at 2θ values typical of CuONPs. FTIR spectra exhibited bands associated with organic functional groups confirming capping and functionalization of the CuONPs by the phytochemicals. DLS analysis registered a net zeta potential of +12.5 mV. SEM analysis revealed that the nanoparticles were spherical and clustered with a mean diameter of 6 nm. Phytosynthesized CuONPs exhibited the highest growth suppression zones of 30 mm with MIC ranging from 30 to 125 μg/ml against MDR bacteria. Furthermore, the CuONPs achieved a methylene blue dye photocatalysis degradation efficiency of 85.5% and a free radical scavenging activity of 28.8%. PAE and CSE successfully bio-reduced copper ions to the nanoscale level with potent antimicrobial, photocatalysis, and antioxidant activities.

Recent Advancements in Plant-Derived Nanomaterials Research for Biomedical Applications

Engineering, physics, chemistry, and biology are all involved in nanotechnology, which comprises a wide variety of multidisciplinary scientific field devices. The holistic utilization of metallic nanoparticles in the disciplines of bio-engineering and bio-medicine has attracted a great deal of attention. Medical nanotechnology research can offer immense health benefits for humans. While the advantages of developing nanomaterials have been well documented, it is precisely apparent that there are still some major issues that remain unattended to those need to be resolved immediately so as to ensure that they do not adversely affect living organisms in any manner. The existence of nanoparticles gives them particular value in biology and materials science, as an emerging scientific field, with multiple applications in science and technology, especially with numerous frontiers in the development of new materials. Presented here is a review of recent noteworthy developments regarding plant-derived nanomaterials and their use in the development of medicine and biomedical applications around the world.

One-pot synthesis of a highly disperse core–shell CuO–alginate nanocomposite and the investigation of its antibacterial and catalytic properties

Sodium alginate extracted from native algae of the Persian Gulf for use in the synthesis of a highly disperse CuO–alginate nanocomposite, which is used as an antibacterial agent as well as a catalyst in the synthesis of amides.

Past and Current Progress in the Development of Antiviral/Antimicrobial Polymer Coating towards COVID-19 Prevention: A Review

The astonishing outbreak of SARS-CoV-2 coronavirus, known as COVID-19, has attracted numerous research interests, particularly regarding fabricating antimicrobial surface coatings. This initiative is aimed at overcoming and minimizing viral and bacterial transmission to the human. When contaminated droplets from an infected individual land onto common surfaces, SARS-CoV-2 coronavirus is able to survive on various surfaces for up to 9 days. Thus, the possibility of virus transmission increases after touching or being in contact with contaminated surfaces. Herein, we aim to provide overviews of various types of antiviral and antimicrobial coating agents, such as antimicrobial polymer-based coating, metal-based coating, functional nanomaterial, and nanocomposite-based coating. The action mode for each type of antimicrobial agent against pathogens is elaborated. In addition, surface properties of the designed antiviral and antimicrobial polymer coating with their influencing factors are discussed in this review. This paper also exhibits several techniques on surface modification to improve surface properties. Various developed research on the development of antiviral/antimicrobial polymer coating to curb the COVID-19 pandemic are also presented in this review.

CuO Bionanocomposite with Enhanced Stability and Antibacterial Activity against Extended-Spectrum Beta-Lactamase Strains

Worldwide, bacterial resistance to beta-lactam antibiotics is the greatest challenge in public health care. To overcome the issue, metal-based nanoparticles were extensively used as an alternative to traditional antibiotics. However, their unstable nature limits their use. In the present study a very simple, environmentally friendly, one-pot synthesis method that avoids the use of organic solvents has been proposed to design stable, novel nanocomposites. Formulation was done by mixing biogenic copper oxide (CuO) nanomaterial with glycerol and phospholipids isolated from egg yolk in an appropriate ratio at optimum conditions. Characterization was done using dynamic light scattering DLS, Zeta potential, high performance liquid chromatography (HPLC), and transmission electron microscopy (TEM). Further, its antibacterial activity was evaluated against the extended-spectrum beta-lactamase strains based on zone of inhibition and minimal inhibitory concentration (MIC) indices. Results from this study have demonstrated the formulation of stable nanocomposites with a zeta potential of 34.9 mV. TEM results indicated clear dispersed particles with an average of 59.3 ± 5 nm size. Furthermore, HPLC analysis of the egg yolk extract exhibits the presence of phospholipids in the sample and has significance in terms of stability. The newly formed nanocomposite has momentous antibacterial activity with MIC 62.5 μg/mL. The results suggest that it could be a good candidate for drug delivery in terms of bactericidal therapeutic applications.

Copper oxide nanoparticles synthesized from an endophytic fungus Aspergillus terreus: Bioactivity and anti-cancer evaluations

The mycofabricated metal nanoparticles (NPs) plays a significant role in cancer therapeutics and imparts a strategy in medicine. The current investigation focused to synthesize the Copper Oxide Nanoparticles (CuONPs) using an endophytic fungus isolated from Aegle marmelosa medicinal tree located in Western Ghats, India. The endophytic fungus FCBY1 explored the highest antagonistic and antioxidant activities among the 16 pigmented endophytic fungal strains which were isolated from the collected samples. The fungus FCBY1 was identified for its morphological and molecular characteristics where the (Internal Transcribed Spacer) ITS 1, 5.8 ribosomal gene and ITS 2 were sequenced; and the organism FCBY1 is Aspergillus terreus. The endophyte was put through for the synthesis of CuONPs and the size and structure of the synthesized particles were characterized by Scanning Electron Microscope (SEM). The confirmation of the CuONPs was characterized by FT-IR, EDAX and XRD analyses. The CuONPs exhibited the maximized antibacterial and antifungal activities against the human clinical pathogens; moreover the particles also explicated the free radicals/ROS scavenging at minimum concentration, which was assessed through DPPH, nitric oxide radical scavenging assays, and reductive power ability. The anti-cancer activity of CuONPs on colon cancer cell lines (HT-29) was evaluated by MTT (IC50: 22 μg/mL) and FACS analyses (32.11% cells gated in S phase of cell cycle). Angiogenesis inhibition in tumor cells was estimated through in vivo HET- CAM assessment and the highest concentration 60 μL tested inhibited the blood vessels at the percentage of 31.36% and 81.81%. The CuONPs explicated the anti-cancer activities in a concentration - dependent manner and the results of this investigation manifest the significant role of the CuONPs in cancer therapeutics.

Endophytic Nanotechnology: An Approach to Study Scope and Potential Applications

Nanotechnology has become a very advanced and popular form of technology with huge potentials. Nanotechnology has been very well explored in the fields of electronics, automobiles, construction, medicine, and cosmetics, but the exploration of nanotecnology's use in agriculture is still limited. Due to climate change, each year around 40% of crops face abiotic and biotic stress; with the global demand for food increasing, nanotechnology is seen as the best method to mitigate challenges in disease management in crops by reducing the use of chemical inputs such as herbicides, pesticides, and fungicides. The use of these toxic chemicals is potentially harmful to humans and the environment. Therefore, using NPs as fungicides/ bactericides or as nanofertilizers, due to their small size and high surface area with high reactivity, reduces the problems in plant disease management. There are several methods that have been used to synthesize NPs, such as physical and chemical methods. Specially, we need ecofriendly and nontoxic methods for the synthesis of NPs. Some biological organisms like plants, algae, yeast, bacteria, actinomycetes, and fungi have emerged as superlative candidates for the biological synthesis of NPs (also considered as green synthesis). Among these biological methods, endophytic microorganisms have been widely used to synthesize NPs with low metallic ions, which opens a new possibility on the edge of biological nanotechnology. In this review, we will have discussed the different methods of synthesis of NPs, such as top-down, bottom-up, and green synthesis (specially including endophytic microorganisms) methods, their mechanisms, different forms of NPs, such as magnesium oxide nanoparticles (MgO-NPs), copper nanoparticles (Cu-NPs), chitosan nanoparticles (CS-NPs), β-d-glucan nanoparticles (GNPs), and engineered nanoparticles (quantum dots, metalloids, nonmetals, carbon nanomaterials, dendrimers, and liposomes), and their molecular approaches in various aspects. At the molecular level, nanoparticles, such as mesoporous silica nanoparticles (MSN) and RNA-interference molecules, can also be used as molecular tools to carry genetic material during genetic engineering of plants. In plant disease management, NPs can be used as biosensors to diagnose the disease.

Study of antimicrobial activity of Unani poly herbal toothpaste "Sunoon Zard"

Objective

The present study was envisioned to develop Sunoon Zard a traditional Unani toothpowder into toothpaste form along with its physicochemical standardization and evaluation of anti microbial activity against oral pathogens by in vitro study.

Materials and methods

Herbal extracts based powder was redesigned to toothpaste as per the Pharmacopoeial guidelines and its pharmaceutical evaluation was conceded as per the Indian Government Tooth Paste Specifications. In vitro study was done to evaluate the antibacterial activity by using agar well diffusion method against dental pathogens. Zone of Inhibition was taken as the end parameter against the test pathogens after appropriate incubation period. It was compared with Dimethyl sulphoxide (DMSO) used as solvent (0.01%) as Negative control whereas Ciprofloxacin 5μg/disk (standard antibiotic for gram positive) and Gentamicin 10μg/disk (standard antibiotic for gram negative) were used as Positive control. All the experiment was done as per the Clinical and Laboratory Standards Institute (CLSI) Guidelines in triplicates.

Results

Sunoon Zard was developed into toothpaste form and its physicochemical values were found to in consonance with the optimum values as mentioned in Bureau of Indian Standard. In vitro study of the Sunoon Zard toothpaste was found to be effective against various dental pathogens with specific sensitivity with good zone of inhibition towards gram negative bacterial strains viz. P.aeruginosa and K.pneuomoniae while among gram positive a significant inhibition was found against C.xerosis and S.viridans.

Conclusion

The developed toothpaste from classical Unani herbal tooth powder will provide the better patient compliance. Moreover its scientific screening which exhibited potential antibacterial activity in controlling pathogenic oral microflora compared to the standard drugs also revalidated the claim of Unani Physicians that the Sunoon Zard is quite effective in various oro-dental disorders.

Multimetallic Nanoparticles as Alternative Antimicrobial Agents: Challenges and Perspectives

Recently, infectious diseases caused by bacterial pathogens have become a major cause of morbidity and mortality globally due to their resistance to multiple antibiotics. This has triggered initiatives to develop novel, alternative antimicrobial materials, which solve the issue of infection with multidrug-resistant bacteria. Nanotechnology using nanoscale materials, especially multimetallic nanoparticles (NPs), has attracted interest because of the favorable physicochemical properties of these materials, including antibacterial properties and excellent biocompatibility. Multimetallic NPs, particularly those formed by more than two metals, exhibit rich electronic, optical, and magnetic properties. Multimetallic NP properties, including size and shape, zeta potential, and large surface area, facilitate their efficient interaction with bacterial cell membranes, thereby inducing disruption, reactive oxygen species production, protein dysfunction, DNA damage, and killing potentiated by the host's immune system. In this review, we summarize research progress on the synergistic effect of multimetallic NPs as alternative antimicrobial agents for treating severe bacterial infections. We highlight recent promising innovations of multimetallic NPs that help overcome antimicrobial resistance. These include insights into their properties, mode of action, the development of synthetic methods, and combinatorial therapies using bi- and trimetallic NPs with other existing antimicrobial agents.

Green-synthesized copper oxide nanostructures for potential multifaceted biomedical applications

The novelty of the present work is the in-vitro and in vivo nano-antibitoic combinational therapy along with in vitro anti-cancer and biocompatibility activities of green synthesized CuO NLs.