Metal Oxide Nanoparticles: Review of Synthesis, Characterization and Biological Effects

Zingerone based green synthesized sodium doped zinc oxide nanoparticles eliminate U87 glioblastoma cells by inducing apoptosis

Grade IV astrocytoma, also referred to as glioblastoma (GBM), is the most common type of glioma, accounting for over 60% of all brain tumors. It is still a fatal illness in spite of years of investigation and does not currently have a treatment. Thus, scientists and medical professionals are constantly trying to understand the molecular processes and heterogeneity of GBM as well as looking for new ways to improve treatment results. Numerous studies have indicated that nanomaterials, and more especially nanoparticles, offer a great deal of potential for killing cancer cells; as a result, they are being considered as a potential alternative cancer treatment. Several studies have demonstrated that ZnO NPs have shown specific cytotoxicity against cancer cells while leaving normal cells unharmed. In this study we aim to synthesize sodium doped zinc oxide NPs using zingerone in an environmentally friendly manner to evaluate their cytotoxic effects on U87 GBM cell line and normal HEK cell line and investigate the occurrence of apoptosis via apoptosis assay by flowcytometry and gene expression study of TP53 and related genes to apoptosis and cell cycle regulation pathways. It was demonstrated that Na-doped ZnO NPs had a significant cytotoxic effect on U87 cells while having significantly less effect on normal HEK cells. Na-doped ZnO NPs eliminated cancerous cells through apoptosis induction and possibly cell cycle regulation via up-regulation of TP53, PTEN, BAX, P21 and down-regulation of Bcl2. The unique physicochemical properties of nanoparticles turn them into fascinating agents to treat GBM. Hence, the necessity of exploring the vast, yet unknown field of nanoparticles potentials cannot be over looked.

Artificial Bone Materials for Infected Bone Defects: Advances in Antimicrobial Functions

Infected bone defects, caused by bacterial contamination following disease or injury, result in the partial loss or destruction of bone tissue. Traditional bone transplantation and other clinical approaches often fail to address the therapeutic complexities of these conditions effectively. In recent years, advanced biomaterials have attracted significant attention for their potential to enhance treatment outcomes. This review explores the pathogenic mechanisms underlying infected bone defects, including biofilm formation and bacterial internalization into bone cells, which allow bacteria to evade the host immune system. To control bacterial infection and facilitate bone repair, we focus on antibacterial materials for bone regeneration. A detailed introduction is given on intrinsically antibacterial materials (e.g., metal alloys, oxide materials, carbon-based materials, hydroxyapatite, chitosan, and Sericin). The antibacterial functionality of bone repair materials can be enhanced through strategies such as the incorporation of antimicrobial ions, surface modification, and the combined use of multiple materials to treat infected bone defects. Key innovations discussed include biomaterials that release therapeutic agents, functional contact biomaterials, and bioresponsive materials, which collectively enhance antibacterial efficacy. Research on the clinical translation of antimicrobial bone materials has also facilitated their practical application in infection prevention and bone healing. In conclusion, advancements in biomaterials provide promising pathways for developing more biocompatible, effective, and personalized therapies to reconstruct infected bone defects.

Determination of metal oxide and metallic nanoparticles in indoor air samples using mixed cellulose esters filters and spICP-MS: dissolve and shoot

In recent years, there has been increasing concern about the adverse health effects of the metallic and metal-containing nanoparticles (NPs) present in indoor environments. Unfortunately, there is no well-stablish method to simultaneously characterize their number and composition. Recently, our research group proposed a strategy for the determination of metallic nanoparticles in air by means spICP-MS based on the aerosol collection on micro-quartz filters and the subsequent extraction using microwave heating in basic media. Although the proposed method allows accurate and precise characterization of NPs, it suffers from practical drawbacks: (i) micro-quartz filter fibers are released into the sample and must be removed prior to analysis to avoid clogging the nebulizer and (ii) the particle distribution detection limits (LODsize) achieved are not low enough (28 nm). In this work, we evaluate the NPs trapping capabilities and possible fiber release of filters of different nature commonly used for indoor air quality control (polytetrafluoroethylene (PTFE), nylon, polycarbonate, and mixed cellulose ester (MCE) filters) and NPs of different chemical composition (ZrO2-, TiO2-, Pt-, AuNPs), size (20-150 nm), and capping agent (citrate, polyethylene glycol, branched polyethyleneimine, and lipoic acid). The results show that MCE is an optimal solution because it is completely dissolved during the microwave heating step and NPs are recovered quantitatively irrespective of their composition and size. The LODs are also improved down to 15 nm and 120 particles per liter of air, low enough to be used for indoor air pollution control. Finally, the proposed method was successfully tested in a simulated (NPs enriched) indoor environment.

Plant extract-mediated green-synthesized CuO nanoparticles for environmental and microbial remediation: a review covering basic understandings to mechanistic study

This review provides a comprehensive overview of nanoparticles, with a particular focus on plant extract-mediated green-synthesized copper oxide nanoparticles (CuO NPs). This article is one of the simplest to read as it aims at beginner researchers, who may not have advanced knowledge on topics like nanoparticles, including metal and metal oxide nanoparticles, their classification, and techniques to prepare them. Various synthesis procedures are discussed, emphasizing green synthesis methods that utilize plant extracts as reducing and stabilizing agents. Subsequently, the mechanisms involved in the formation of CuO NPs are highlighted. Their significant applications with a mechanistic overview on environmental remediation, especially in the eradication of textile dyes and pharmaceutical wastes, and their antimicrobial properties are elucidated. By carefully scrutinizing the information available in the literature, this article aims to equip novice researchers with a foundational understanding of nanoparticles, their synthesis, and their practical applications, fostering further exploration in the field of nanotechnology.

Beyond antibiotics: exploring multifaceted approaches to combat bacterial resistance in the modern era: a comprehensive review

Antibiotics represent one of the most significant medical breakthroughs of the twentieth century, playing a critical role in combating bacterial infections. However, the rapid emergence of antibiotic resistance has become a major global health crisis, significantly complicating treatment protocols. This paper provides a narrative review of the current state of antibiotic resistance, synthesizing findings from primary research and comprehensive review articles to examine the various mechanisms bacteria employ to counteract antibiotics. One of the primary sources of antibiotic resistance is the improper use of antibiotics in the livestock industry. The emergence of drug-resistant microorganisms from human activities and industrial livestock production has presented significant environmental and public health concerns. Today, resistant nosocomial infections occur following long-term hospitalization of patients, causing the death of many people, so there is an urgent need for alternative treatments. In response to this crisis, non-antibiotic therapeutic strategies have been proposed, including bacteriophages, probiotics, postbiotics, synbiotics, fecal microbiota transplantation (FMT), nanoparticles (NPs), antimicrobial peptides (AMPs), antibodies, traditional medicines, and the toxin-antitoxin (TA) system. While these approaches offer innovative solutions for addressing bacterial infections and preserving the efficacy of antimicrobial therapies, challenges such as safety, cost-effectiveness, regulatory hurdles, and large-scale implementation remain. This review examines the potential and limitations of these strategies, offering a balanced perspective on their role in managing bacterial infections and mitigating the broader impact of antibiotic resistance.

Ovalbumin-Mediated Biogenic Synthesis of ZnO and MgO Nanostructures: A Path Toward Green Nanotechnology

Sustainable and eco-friendly synthesis methods for nanoparticles are crucial for advancing green nanotechnology. This study presents the biogenic synthesis of zinc oxide (ZnO) and magnesium oxide (MgO) nanoparticles using ovalbumin, an abundant and non-toxic protein from egg white. The synthesis process was optimized by varying metal ion concentrations to control particle size and morphology. Characterization using ATR-FTIR, XRD, SEM, and UV-VIS confirmed the successful formation of uniform, well-crystallized nanoparticles with sizes ranging from 7.9 to 13.5 nm. ZnO nanoparticles exhibited superior antimicrobial efficacy against Escherichia coli and Enterococcus faecalis, while MgO nanoparticles showed enhanced potential environmental remediation. These findings highlight ovalbumin as a versatile agent for the green synthesis of ZnO and MgO nanomaterials, with promising applications in the medical, environmental, and optoelectronic fields. The results indicate that this biogenic method can serve as a sustainable proposal to produce nanostructured materials with diverse applications in the medical and environmental fields, such as eliminating pathogenic bacteria and purifying contaminated environments. Overall, this study significantly contributes to the development of sustainable nanomaterials and opens up new perspectives on the use of ovalbumin protein in the synthesis of multifunctional nanostructured materials.

A review of recent progress in alginate-based nanocomposite materials for tissue engineering applications

Integrating nanotechnology with tissue engineering has revolutionized biomedical sciences, enabling the development of advanced therapeutic strategies. Tissue engineering applications widely utilize alginate due to its biocompatibility, mild gelation conditions, and ease of modification. Combining different nanomaterials with alginate matrices enhances the resulting nanocomposites' physicochemical properties, such as mechanical, electrical, and biological properties, as well as their surface area-to-volume ratio, offering significant potential for tissue engineering applications. This review thoroughly overviews various nanomaterials, such as metal and metal oxide nanoparticles, carbon-based nanomaterials, MXenes, and hydroxyapatite, that modify alginate-based nanocomposites. It covers multiple preparation techniques, including layer-by-layer assembly, blending, 3D printing, and in situ synthesis. These techniques apply to tissue engineering applications, including bone tissue engineering, cardiac tissue engineering, neural tissue engineering, wound healing, and skin regeneration. Additionally, it highlights current advancements, challenges, and future perspectives.

Quercetin protective potential against nanoparticle-induced adverse effects

The rapid development of nanotechnology has resulted in the widespread use of nanoparticles (NPs) in various sectors due to their unique properties and diverse applications. However, the increased exposure of humans to NPs raises concerns about their potential negative impact on human health and the environment. The pathways through which NPs exert adverse effects, including inflammation and oxidative stress, are primarily influenced by their size, shape, surface charge, and chemistry, underscoring the critical need to comprehend and alleviate their potential detrimental impacts. In this context, the natural flavonoid quercetin is a promising candidate for counteracting the toxicity induced by NPs due to its anti-inflammatory and antioxidant properties. This review provides an overview of the existing literature on quercetin's protective effects against NPs-induced toxicity, highlighting its therapeutic benefits and mechanisms of action, focusing on its ability to alleviate oxidative stress, inflammation, and cellular damage caused by various types of NPs. Insights from both in vitro and in vivo studies demonstrate the effectiveness of quercetin in preserving cellular function, modulating apoptotic pathways, and maintaining tissue integrity in the presence of NPs. The potential of quercetin as a natural therapeutic agent against NPs-induced toxicity provides valuable insights for safer use of NPs in various daily applications.

Galleria mellonella (Greater Wax Moth) as a Reliable Animal Model to Study the Efficacy of Nanomaterials in Fighting Pathogens

The spread of multidrug-resistant microbes has made it necessary and urgent to develop new strategies to deal with the infections they cause. Some of these are based on nanotechnology, which has revolutionized many fields in medicine. Evaluating the safety and efficacy of these new antimicrobial strategies requires testing in animal models before being tested in clinical trials. In this context, Galleria mellonella could represent a valid alternative to traditional mammalian and non-mammalian animal models, due to its low cost, ease of handling, and valuable biological properties to investigate host-pathogen interactions. The purpose of this review is to provide an updated overview of the literature concerning the use of G. mellonella larvae as an animal model to evaluate safety and efficacy of nanoparticles and nanomaterials, particularly, of those that are used or are under investigation to combat microbial pathogens.

Cancer treatment approaches within the frame of hyperthermia, drug delivery systems, and biosensors: concepts and future potentials

This work presents a review of the therapeutic modalities and approaches for cancer treatment. A brief overview of the traditional treatment routes is presented in the introduction together with their reported side effects. A combination of the traditional approaches was reported to demonstrate an effective therapy until a few decades ago. With the improvement in the fabrication of nanomaterials, targeted therapy represents a novel therapeutic approach. This improvement established on nanoparticles is categorized into hyperthermia, drug delivery systems, and biosensors. Hyperthermia presents a personalized medicine-based approach in which targeted zones are heated up until the diseased tissue is destroyed by the thermal effect. The use of magnetic nanoparticles further improved the effectiveness of hyperthermia owing to the enhanced heating action, further increasing the accuracy of the targeting process. Nanoparticle-based biosensors present a smart nanodevice that can detect, monitor, and target tumor tissues by following the biomarkers in the body fluids. Magnetic nanoparticles offer a controlled thermo-responsive device that can be manipulated by changing the magnetic field, offering a more personalized and controlled hyperthermia therapeutic modality. Similarly, gold nanoparticles offer an effective aid in the hyperthermia treatment approach. Furthermore, carbon nanotubes and metal-organic frameworks present a cutting-edge approach to cancer treatment. A combination of functionalized nanoparticles offers a unique route for drug delivery systems, in which therapeutic agents carried by nanoparticles are guided into the human body and then released in the target spot.

Targeting the tumor microenvironment with biomaterials for enhanced immunotherapeutic efficacy

The tumor microenvironment (TME) is a complex system characterized by low oxygen, low pH, high pressure, and numerous growth factors and protein hydrolases that regulate a wide range of biological behaviors in the tumor and have a profound impact on cancer progression. Immunotherapy is an innovative approach to cancer treatment that activates the immune system, resulting in the spontaneous killing of tumor cells. However, the therapeutic efficacy of these clinically approved cancer immunotherapies (e.g., immune checkpoint blocker (ICB) therapies and chimeric antigen receptor (CAR) T-cell therapies) is far from satisfactory due to the presence of immunosuppressive TMEs created in part by tumor hypoxia, acidity, high levels of reactive oxygen species (ROS), and a dense extracellular matrix (ECM). With continuous advances in materials science and drug-delivery technologies, biomaterials hold considerable potential for targeting the TME. This article reviews the advances in biomaterial-based targeting of the TME to advance our current understanding on the role of biomaterials in enhancing tumor immunity. In addition, the strategies for remodeling the TME offer enticing advantages; however, the represent a double-edged sword. In the process of reshaping the TME, the risk of tumor growth, infiltration, and distant metastasis may increase.

Green Synthesis of Zinc Oxide Nanoparticles Using Puerarin: Characterization, Antimicrobial Potential, Angiogenesis, and In Ovo Safety Profile Assessment

BACKGROUND

Zinc oxide nanobiocomposites were successfully synthesized using a green synthesis approach. The process involves the utilization of the isoflavone puerarin, resulting in the formation of PUE-ZnO NPs.

METHODS

Physico-chemical and biological characterization techniques including X-ray dif-fraction (XRD), UV-vis spectroscopy, Fourier transform infrared spectroscopy (ATR-FTIR), scanning electron microscopy (SEM), atomic force microscopy (AFM), and in ovo methods were employed to study the main characteristics of this novel hybrid material.

RESULTS

The PUE-ZnO NPs were confirmed to have been successfully synthesized with a UV absorption peak at 340 nm, the XRD analysis demonstrating their high purity and crystallinity. The energy band-gap value of 3.30 eV suggests possible photocatalytic properties. Both SEM and AFM images revealed the nanoparticle`s quasi-spherical shape, roughness, and size. Good tolerability and anti-irritative effects were recorded in ovo on the chorioallantoic membrane (CAM).

CONCLUSIONS

According to these results, the synthesis of green PUE-ZnO NPs may be a promising future approach for biomedical and personal care applications.

Eco-friendly synthesis, characterization, and properties of copper oxide nanoparticles in cashew gum/polypyrrole blend for energy storage applications

Conducting biopolymer blend nanocomposites of cashew gum (CG) and polypyrrole (PPy), with varying concentrations of copper oxide (CuO) nanoparticles were synthesized through an in-situ polymerization method using water as a sustainable solvent. The formation of blend nanocomposites was characterized using UV-visible (UV-vis) spectroscopy, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). UV spectroscopy revealed a significant reduction in absorption intensity with the addition of CuO, indicating enhanced optical properties. FT-IR and XRD analysis confirmed the successful incorporation of CuO into the CG/PPy blend. FE-SEM images revealed the uniform distribution of nanoparticles throughout the biopolymer blend, particularly in the 7 wt% sample. TGA and DSC results demonstrated a significant enhancement in thermal stability, increasing from 352 °C to 412 °C and a rise in the glass transition temperature from 89 °C to 106 °C in the blend nanocomposites. The dielectric constant, dielectric loss, impedance, Nyquist plot, electrical conductivity, and electric modulus were extensively examined at different temperatures and frequencies. The dielectric constant of the CG/PPy blend increased from 2720 to 92,950 with the addition of 7 wt% CuO, measured at 100 Hz. The improved glass transition temperature, thermal stability, and superior electrical properties imply potential usage of the developed nanocomposite in nanoelectronics and energy storage applications.

Design of a nanozyme-based magnetic nanoplatform to enhance photodynamic therapy and immunotherapy

The tumor microenvironment, particularly the hypoxic property and glutathione (GSH) overexpression, substantially inhibits the efficacy of cancer therapy. In this article, we present the design of a magnetic nanoplatform (MNPT) comprised of a photosensitizer (Ce6) and an iron oxide (Fe3O4)/manganese oxide (MnO2) composite nanozyme. Reactive oxygen species (ROS), such as singlet oxygen (1O2) radicals produced by light irradiation and hydroxyl radicals (·OH) produced by catalysis, are therapeutic species. These therapeutic substances stimulate cell apoptosis by increasing oxidative stress. This apoptosis then triggers the immunological response, which combines photodynamic therapy and T-cell-mediated immunotherapy to treat cancer. Furthermore, MNPT can be utilized as a contrast agent in magnetic resonance and fluorescence dual-modality imaging to give real-time tracking and feedback on treatment.

Inflammatory response of nanoparticles: Mechanisms, consequences, and strategies for mitigation

Numerous nano-dimensioned materials have been generated as a result of several advancements in nanoscale science such as metallic nanoparticles (mNPs) which have aided in the advancement of related research. As a result, several significant nanoscale materials are being produced commercially. It is expected that in the future, products that are nanoscale, like mNPs, will be useful in daily life. Despite certain benefits, widespread use of metallic nanoparticles and nanotechnology has negative effects and puts human health at risk because of their continual accumulation in closed biological systems, along with their complex and diverse migratory and transformation pathways. Once within the human body, nanoparticles (NPs) disrupt the body's natural biological processes and trigger inflammatory responses. These NPs can also affect the immune system by activating separate pathways that either function independently or interact with one another. Cytotoxic effects, inflammatory response, genetic material damage, and mitochondrial dysfunction are among the consequences of mNPs. Oxidative stress and reactive oxygen species (ROS) generation caused by mNPs depend upon a multitude of factors that allow NPs to get inside cells and interact with biological macromolecules and cell organelles. This review focuses on how mNPs cause inflammation and oxidative stress, as well as disrupt cellular signaling pathways that support these effects. In addition, possibilities and problems to be reduced are addressed to improve future research on the creation of safer and more environmentally friendly metal-based nanoparticles for commercial acceptance and sustainable use in medicine and drug delivery.

Souza AB, Levita DP, Mello CC, da Silva AFM, dos Santos TC, Ronconi CM. Innovating Leishmaniasis Treatment: A Critical Chemist's Review of Inorganic Nanomaterials

Leishmaniasis, a critical Neglected Tropical Disease caused by Leishmania protozoa, represents a significant global health risk, particularly in resource-limited regions. Conventional treatments are effective but suffer from serious limitations, such as toxicity, prolonged treatment courses, and rising drug resistance. Herein, we highlight the potential of inorganic nanomaterials as an innovative approach to enhance Leishmaniasis therapy, aligning with the One Health concept by considering these treatments' environmental, veterinary, and public health impacts. By leveraging the adjustable properties of these nanomaterials─including size, shape, and surface charge, tailored treatments for various diseases can be developed that are less harmful to the environment and nontarget species. We review recent advances in metal-, oxide-, and carbon-based nanomaterials for combating Leishmaniasis, examining their mechanisms of action and their dual use as standalone treatments or drug delivery systems. Our analysis highlights a promising yet underexplored frontier in employing these materials for more holistic and effective disease management.

Advances in hybridized nanoarchitectures for improved oro-dental health

On a global note, oral health plays a critical role in improving the overall human health. In this vein, dental-related issues with dentin exposure often facilitate the risk of developing various oral-related diseases in gums and teeth. Several oral-based ailments include gums-associated (gingivitis or periodontitis), tooth-based (dental caries, root infection, enamel erosion, and edentulous or total tooth loss), as well as miscellaneous diseases in the buccal or oral cavity (bad breath, mouth sores, and oral cancer). Although established conventional treatment modalities have been available to improve oral health, these therapeutic options suffer from several limitations, such as fail to eradicate bacterial biofilms, deprived regeneration of dental pulp cells, and poor remineralization of teeth, resulting in dental emergencies. To this end, the advent of nanotechnology has resulted in the development of various innovative nanoarchitectured composites from diverse sources. This review presents a comprehensive overview of different nanoarchitectured composites for improving overall oral health. Initially, we emphasize various oral-related diseases, providing detailed pathological circumstances and their effects on human health along with deficiencies of the conventional therapeutic modalities. Further, the importance of various nanostructured components is emphasized, highlighting their predominant actions in solving crucial dental issues, such as anti-bacterial, remineralization, and tissue regeneration abilities. In addition to an emphasis on the synthesis of different nanostructures, various nano-therapeutic solutions from diverse sources are discussed, including natural (plant, animal, and marine)-based components and other synthetic (organic- and inorganic-) architectures, as well as their composites for improving oral health. Finally, we summarize the article with an interesting outlook on overcoming the challenges of translating these innovative platforms to clinics.

Influence of Physicochemical Properties of Iron Oxide Nanoparticles on Their Antibacterial Activity

The increasing occurrence of infectious diseases caused by antimicrobial resistance organisms urged the necessity to develop more potent, selective, and safe antimicrobial agents. The unique magnetic and tunable properties of iron oxide nanoparticles (IONPs) make them a promising candidate for different theragnostic applications, including antimicrobial agents. Though IONPs act as a nonspecific antimicrobial agent, their antimicrobial activities are directly or indirectly linked with their synthesis methods, synthesizing precursors, size, shapes, concentration, and surface modifications. Alteration of these parameters could accelerate or decelerate the production of reactive oxygen species (ROS). An increase in ROS role production disrupts bacterial cell walls, cell membranes, alters major biomolecules (e.g., lipids, proteins, nucleic acids), and affects metabolic processes (e.g., Krebs cycle, fatty acid synthesis, ATP synthesis, glycolysis, and mitophagy). In this review, we will investigate the antibacterial activity of bare and surface-modified IONPs and the influence of physiochemical parameters on their antibacterial activity. Additionally, we will report the potential mechanism of IONPs' action in driving this antimicrobial activity.

Eco-synthesis route: Developing bis-hydrazono[1,2,4]-thiadiazoles via a green synthetic approach with calcium oxide-chitosan nanocomposite

Modern environmental organic chemistry is focused on developing cost-efficient, versatile, environmentally acceptable catalytic chemicals that are also highly effective. Herein, hybrid calcium-chitosan nanocomposite films was prepared by doping calcium oxide molecules into a chitosan matrix at weight percentage (15, 20, and 25 % wt. chitosan‑calcium) using an easy and affordable simple co-precipitation process. The CS-CaO nanocomposite's structure was elucidated using analytical techniques such as Fourier transform infrared (FTIR), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). Based on the X ray diffraction (XRD) measurements, the crystallinity was reduced by the incorporation of the CaO molecules. Also, from the calculation of the Debye-Scherrer equation on this X-ray diffraction (XRD) pattern, the crystallite size was found to be 17.2 nm for the nanocomposite film with 20 % wt. The energy dispersive spectroscopy graph demonstrated the presence of the distinctive Ca element signals within the chitosan, with the amount in a sample of 20 % wt. being discovered to be 21.32 % wt. For the synthesis of bis-hydrazono[1,2,4]thiadiazoles, the obtained CS-CaO nanocomposite could be employed as a potent heterogeneous recyclable catalyst. Better reaction yields, quicker reactions, softer reaction conditions, and green reusable efficient biocatalysts for several uses are just a few advantages of this approach.

Nanoformulations in Pharmaceutical and Biomedical Applications: Green Perspectives

This study provides a brief discussion of the major nanopharmaceuticals formulations as well as the impact of nanotechnology on the future of pharmaceuticals. Effective and eco-friendly strategies of biofabrication are also highlighted. Modern approaches to designing pharmaceutical nanoformulations (e.g., 3D printing, Phyto-Nanotechnology, Biomimetics/Bioinspiration, etc.) are outlined. This paper discusses the need to use natural resources for the "green" design of new nanoformulations with therapeutic efficiency. Nanopharmaceuticals research is still in its early stages, and the preparation of nanomaterials must be carefully considered. Therefore, safety and long-term effects of pharmaceutical nanoformulations must not be overlooked. The testing of nanopharmaceuticals represents an essential point in their further applications. Vegetal scaffolds obtained by decellularizing plant leaves represent a valuable, bioinspired model for nanopharmaceutical testing that avoids using animals. Nanoformulations are critical in various fields, especially in pharmacy, medicine, agriculture, and material science, due to their unique properties and advantages over conventional formulations that allows improved solubility, bioavailability, targeted drug delivery, controlled release, and reduced toxicity. Nanopharmaceuticals have transitioned from experimental stages to being a vital component of clinical practice, significantly improving outcomes in medical fields for cancer treatment, infectious diseases, neurological disorders, personalized medicine, and advanced diagnostics. Here are the key points highlighting their importance. The significant challenges, opportunities, and future directions are mentioned in the final section.

A review on metal/metal oxide nanoparticles in food processing and packaging

Consuming hygienic and secure food has become challenging for everyone. The preservation of excess food without negatively affecting its nutritional values, shelf life, freshness, or effectiveness would undoubtedly strengthen the food industry. Nanotechnology is a new and intriguing technology that is currently being implemented in the food industry. Metal-based nanomaterials have considerable potential for use in packaging and food processing. These materials have many advanced physical and chemical characteristics. Since these materials are increasingly being used in food applications, there are certain negative health consequences related to their toxicity when swallowed through food. In this article, we have addressed the introduction and applications of metal/metal oxide nanoparticles (MNPs), food processing and food packaging, applications of MNPs-based materials in food processing and food packaging, health hazards, and future perspectives.

Piper chaba Stem Extract Facilitated the Synthesis of Iron Oxide Nanoparticles as an Adsorbent to Remove Congo Red Dye

In this study, a straightforward, eco-friendly, and facile method for synthesizing iron oxide nanoparticles (IONPs) utilizing Piper chaba steam extract as a reducing and stabilizing agent has been demonstrated. The formation of stable IONPs coated with organic moieties was confirmed from UV-vis, FTIR, and EDX spectroscopy and DLS analysis. The produced IONPs are sufficiently crystalline to be superparamagnetic having a saturation magnetization value of 58 emu/g, and their spherical form and size of 9 nm were verified by XRD, VSM, SEM, and TEM investigations. In addition, the synthesized IONPs exhibited notable effectiveness in the removal of Congo Red (CR) dye with a maximum adsorption capacity of 88 mg/g. The adsorption kinetics followed pseudo-second-order kinetics, meaning the adsorption of CR on IONPs is mostly controlled by chemisorption. The adsorption isotherms of CR on the surface of IONPs follow the Langmuir isotherm model, indicating the monolayer adsorption on the homogeneous surface of IONPs through adsorbate-adsorbent interaction. The IONPs have revealed good potential for their reusability, with the adsorption efficiency remaining at about 85% after five adsorption-desorption cycles. The large-scale, safe, and cost-effective manufacturing of IONPs is made possible by this environmentally friendly process.

Nanoparticle-Mediated Hyperthermia and Cytotoxicity Mechanisms in Cancer

Hyperthermia has the potential to damage cancerous tissue by increasing the body temperature. However, targeting cancer cells whilst protecting the surrounding tissues is often challenging, especially when implemented in clinical practice. In this direction, there are data showing that the combination of nanotechnology and hyperthermia offers more successful penetration of nanoparticles in the tumor environment, thus allowing targeted hyperthermia in the region of interest. At the same time, unlike radiotherapy, the use of non-ionizing radiation makes hyperthermia an attractive therapeutic option. This review summarizes the existing literature regarding the use of hyperthermia and nanoparticles in cancer, with a focus on nanoparticle-induced cytotoxicity mechanisms.

Investigating the Cell Entry Mechanism, Disassembly, and Toxicity of the Nanocage PCC-1: Insights into Its Potential as a Drug Delivery Vehicle

The porous coordination cage PCC-1 represents a new platform potentially useful for the cellular delivery of drugs with poor cell permeability and solubility. PCC-1 is a metal-organic polyhedron constructed from zinc metal ions and organic ligands through coordination bonds. PCC-1 possesses an internal cavity that is suitable for drug encapsulation. To better understand the biocompatibility of PCC-1 with human cells, the cell entry mechanism, disassembly, and toxicity of the nanocage were investigated. PCC-1 localizes in the nuclei and cytoplasm within minutes upon incubation with cells, independent of endocytosis and cargo, suggesting direct plasma membrane translocation of the nanocage carrying its guest in its internal cavity. Furthermore, the rates of cell entry correlate to extracellular concentrations, indicating that PCC-1 is likely diffusing passively through the membrane despite its relatively large size. Once inside cells, PCC-1 disintegrates into zinc metal ions and ligands over a period of several hours, each component being cleared from cells within 1 day. PCC-1 is relatively safe for cells at low micromolar concentrations but becomes inhibitory to cell proliferation and toxic above a concentration or incubation time threshold. However, cells surviving these conditions can return to homeostasis 3-5 days after exposure. Overall, these findings demonstrate that PCC-1 enters live cells by crossing biological membranes spontaneously. This should prove useful to deliver drugs that lack this capacity on their own, provided that the dosage and exposure time are controlled to avoid toxicity.

Synthesis and in situ oxidation of copper micro- and nanoparticles by arc discharge plasma in liquid

This work presents a one-step controlled method for the synthesis of copper oxide nanoparticles using an arc discharge in deionized water without subsequent thermal annealing. The synthesis conditions were varied by changing the arc discharge current from 2 to 4 A. Scanning electron microscopy images of samples synthesized at discharge current of 2 A revealed the formation of tenorite (CuO) nanopetals with an average length of 550 nm and a width of 100 nm, which had a large surface area. Arc discharge synthesis at 3 and 4 A current modes provides the formation of a combination of CuO nanopetals with spherical cuprite (Cu2O) nanoparticles with sizes ranging from 30 to 80 nm. The crystalline phase and elemental composition of the synthesized particles were identified by X-ray diffraction analysis, Raman spectroscopy and Energy dispersive analysis. As the arc discharge current was raised from 2 to 4 A, two notable changes occurred in the synthesized particles: the Cu/O ratio increased, and the particle sizes decreased. At 4 A, the synthesized particles were from 30 to 80 nm in size and had a spherical shape, indicating an increase in the amount of cuprite (Cu2O) phase. The optical band gap of the aqueous solutions of copper oxide particles also increased from 2 to 2.34 eV with increasing synthesis current from 2 to 4 A, respectively. This suggests that the proposed synthesis method can be used to tune the band gap of the final material by controlling the Cu/O ratio through the current of arc discharge. Overall, this work demonstrates a novel approach to the synthesis of copper oxide nanoparticles with controllable CuO/Cu2O/Cu ratios, which has the potential to be useful in a variety of applications, particularly due to the significant enhancement of photocatalytic abilities and widen the working spectral range.

Nano-based formulations of curcumin: elucidating the potential benefits and future prospects in skin cancer

Skin cancer refers to any malignant lesions that occur in the skin and are observed predominantly in populations of European descent. Conventional treatment modalities such as excision biopsy, chemotherapy, radiotherapy, immunotherapy, electrodesiccation, and photodynamic therapy (PDT) induce several unintended side effects which affect a patient's quality of life and physical well-being. Therefore, spice-derived nutraceuticals like curcumin, which are well tolerated, less expensive, and relatively safe, have been considered a promising agent for skin cancer treatment. Curcumin, a chemical constituent extracted from the Indian spice, turmeric, and its analogues has been used in various mammalian cancers including skin cancer. Curcumin has anti-neoplastic activity by triggering the process of apoptosis and preventing the multiplication and infiltration of the cancer cells by inhibiting some signaling pathways and thus subsequently preventing the process of carcinogenesis. Curcumin is also a photosensitizer and has been used in PDT. The major limitations associated with curcumin are poor bioavailability, instability, limited permeation into the skin, and lack of solubility in water. This will constrain the use of curcumin in clinical settings. Hence, developing a proper formulation that can ideally release curcumin to its targeted site is important. So, several nanoformulations based on curcumin have been established such as nanogels, nanoemulsions, nanofibers, nanopatterned films, nanoliposomes and nanoniosomes, nanodisks, and cyclodextrins. The present review mainly focuses on curcumin and its analogues as therapeutic agents for treating different types of skin cancers. The significance of using various nanoformulations as well non-nanoformulations loaded with curcumin as an effective treatment modality for skin cancer is also emphasized.

Intraperitoneal hepato-renal toxicity of zinc oxide and nickel oxide nanoparticles in male rats: biochemical, hematological and histopathological studies

In recent years, zinc oxide (ZnO) and nickel oxide (NiO) nanoparticles (NPs) have become more prevalent in commercial and industrial products. However, questions have been raised regarding their potential harm to human health. Limited studies have been conducted on their intraperitoneal toxicity in rats, and their co-exposure effects remain uncertain. Therefore, this study aimed to investigate some biological responses induced by a single intraperitoneal injection of ZnO-NPs (200 mg/kg) and/or NiO-NPs (50 mg/kg) in rats over time intervals. Blood and organ samples were collected from 36 male rats for hematological, biochemical, oxidative stress, and histological analysis. Results showed that the administration of NPs reduced the body and organ weights as well as red blood cell (RBC) indices and altered white blood cell (WBC) and platelet (PLT) counts. The experimental groups exhibited elevated levels of aspartate aminotransferase (AST), alanine transaminase (ALT), creatinine (CREA), urea, lipid profile, glucose (GLU), total protein (TP), albumin (ALB) and malondialdehyde (MDA), and decreased uric acid (UA), superoxide dismutase (SOD), and glutathione (GSH). Histological observations also revealed architectural damages in liver and kidneys. These alterations were time-dependent and varied in their degree of toxicity. Co-exposure of NPs initially lessened the damage but increased it afterwards compared to individual exposure. In conclusion, intraperitoneal injection of ZnO-NPs and/or NiO-NPs alters biological processes and induces oxidative stress in rats' liver and kidneys in a time-dependent manner, with NiO-NPs being more potent than ZnO-NPs. Furthermore, co-exposed NPs initially appeared to be antagonistic to one another while further aiming toward synergism.

Characterization and antimicrobial, antioxidant, and anti-proliferative activities of green synthesized magnesium oxide nanoparticles with shoot extracts of Plicosepalus curviflorus

Objective:

To synthesize magnesium oxide nanoparticles using ethanol extract of shoots of Plicosepalus curviflorus (PC-MgONPs) and evaluate the antimicrobial, antioxidant, and anti-proliferative activities of PC-MgONPs.

Methods:

The green synthesized PC-MgONPs were characterized by ultraviolet-visible (UV), Fourier-transform infrared spectroscopy, zeta potential, energy dispersive X-ray, and scanning electron microscopy. Furthermore, we investigated total antioxidant capacity and antimicrobial and anti-proliferative activities using breast cancer cell lines (MDA-231).

Results:

The UV spectrum of PC-MgONPs showed a sharp absorption peak at 300 nm. The presence of magnesium, oxygen, and sodium was confirmed by energy dispersive X-ray analysis. Scanning electron microscopy revealed PC-MgONPs as roughly spherical granular structures with sizes ranging from 20.0 to 76.4 nm. PC-MgONPs showed considerable antimicrobial activities against Escherichia coli, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans with zones of inhibition of 11-17 mm. In addition, total antioxidant capacity and anti-proliferative activity of PC-MgONPs against MDA-231 cells were dose-dependent.

Conclusions:

The synthesized PC-MgONPs could be a potent antimicrobial, antioxidant and anti-cancer agent, which needs further investigation.

Immobilization of ZnO-TiO2 Nanocomposite into Polyimidazolium Amphiphilic Chitosan Film, Targeting Improving Its Antimicrobial and Antibiofilm Applications

This study presents a green protocol for the fabrication of a multifunctional smart nanobiocomposite (NBC) (ZnO-PIACSB-TiO2) for secure antimicrobial and antibiofilm applications. First, shrimp shells were upgraded to a polyimidazolium amphiphilic chitosan Schiff base (PIACSB) through a series of physicochemical processes. After that, the PIACSB was used as an encapsulating and coating agent to manufacture a hybrid NBC in situ by co-encapsulating ZnONPs and TiO2NPs. The physicochemical and visual characteristics of the new NBC were investigated by spectral, microscopic, electrical, and thermal methods. The antimicrobial indices revealed that the newly synthesized, PIACSB-coated TiO2-ZnO nanocomposite is an exciting antibiotic due to its amazing antimicrobial activity (MIC/MBC→0.34/0.68 μg/mL, 0.20/0.40 μg/mL, and 0.15/0.30 μg/mL working against S. aureus, E. coli, and P. aeruginosa, respectively) and antifungal capabilities. Additionally, ZnO-PIACSB-TiO2 is a potential fighter of bacterial biofilms, with the results being superior to those of the positive control (Cipro), which worked against S. aureus (only 8.7% ± 1.9 biofilm growth), E. coli (only 1.4% ± 1.1 biofilm growth), and P. aeruginosa (only 0.85% ± 1.3 biofilm growth). Meanwhile, the NBC exhibits excellent biocompatibility, as evidenced by its IC50 values against both L929 and HSF (135 and 143 µg/mL), which are significantly higher than those of the MIC doses (0.24-24.85 µg/mL) that work against all tested microbes, as well as the uncoated nanocomposite (IC50 = 19.36 ± 2.04 and 23.48 ± 1.56 µg/mL). These findings imply that the new PIACSB-coated nanocomposite film may offer promising multifunctional food packaging additives to address the customer demand for safe, eco-friendly food products with outstanding antimicrobial and antibiofilm capabilities.

Energy transfer and charge transfer between semiconducting nanocrystals and transition metal dichalcogenide monolayers

Nowadays, as a result of the emergence of low-dimensional hybrid structures, the scientific community is interested in their interfacial carrier dynamics, including charge transfer and energy transfer. By combining the potential of transition metal dichalcogenides (TMDs) and nanocrystals (NCs) with low-dimensional extension, hybrid structures of semiconducting nanoscale matter can lead to fascinating new technological scenarios. Their characteristics make them intriguing candidates for electronic and optoelectronic devices, like transistors or photodetectors, bringing with them challenges but also opportunities. Here, we will review recent research on the combined TMD/NC hybrid system with an emphasis on two major interaction mechanisms: energy transfer and charge transfer. With a focus on the quantum well nature in these hybrid semiconductors, we will briefly highlight state-of-the-art protocols for their structure formation and discuss the interaction mechanisms of energy versus charge transfer, before concluding with a perspective section that highlights novel types of interactions between NCs and TMDs.

Green synthesised zinc oxide nanoparticles reveal potent in vivo and in vitro antibacterial efficacy against Proteus mirabilis isolates

Currently, the spread of antimicrobial resistance dissemination is expanding at an accelerated rate. Therefore, numerous researchers haveinvestigatedalternative treatments in an effort to combat this significant issue. This study evaluated the antibacterial properties of zinc-oxide nanoparticles (ZnO NPs) synthesised by Cycas circinalis against Proteus mirabilis clinical isolates. HPLC was utilised for the identification and quantification of C. circinalis metabolites. The green synthesis of ZnO NPs has been confirmed using UV-VIS spectrophotometry. The Fourier transform infrared spectrum of metal oxide bonds has been compared to the free C. circinalis extract spectrum. The crystalline structure and elemental composition were investigated using X-ray diffraction and Energy-dispersive X-ray techniques. The morphology of nanoparticles was assessed by scanning and transmission electron microscopies, which revealed an average particle size of 26.83±5.87 nm with spherical outlines. The dynamic light scattering technique confirms the optimum stability of ZnO NPs with a zeta potential value equal to 26.4±0.49 mV. Using agar well diffusion and broth microdilution methods, we elucidated the antibacterial activity of ZnO NPs in vitro. MIC values for ZnO NPs ranged from 32 to 128 µg/mL. In 50% of the tested isolates, the membrane integrity was compromised by ZnO nanoparticles. In addition, we assessed the in vivo antibacterial capacity of ZnO NPs by a systemic infection induction using P. mirabilis bacteria in mice. The bacterial count in the kidney tissues was determined, and a significant decrease in CFU/g tissues was observed. The survival rate was evaluated, and the ZnO NPs treated group had higher survival rates. The histopathological studies demonstrated that kidney tissues treated with ZnO NPs had normal structures and architecture. Moreover, the immunohistochemical examinations and ELISA revealed that ZnO NPs substantially decreased the proinflammatory mediators NF-kβ, COX-2, TNF-α, IL-6, and IL-1β in kidney tissues. In conclusion, the results of this study suggest that ZnO NPs are effective against bacterial infections caused by P. mirabilis.

Microwave Synthesis of Visible-Light-Activated g-C3N4/TiO2 Photocatalysts

The preparation of visible-light-driven photocatalysts has become highly appealing for environmental remediation through simple, fast and green chemical methods. The current study reports the synthesis and characterization of graphitic carbon nitride/titanium dioxide (g-C₃N₄/TiO₂) heterostructures through a fast (1 h) and simple microwave-assisted approach. Different g-C₃N₄ amounts mixed with TiO₂ (15, 30 and 45 wt. %) were investigated for the photocatalytic degradation of a recalcitrant azo dye (methyl orange (MO)) under solar simulating light. X-ray diffraction (XRD) revealed the anatase TiO₂ phase for the pure material and all heterostructures produced. Scanning electron microscopy (SEM) showed that by increasing the amount of g-C₃N₄ in the synthesis, large TiO₂ aggregates composed of irregularly shaped particles were disintegrated and resulted in smaller ones, composing a film that covered the g-C₃N₄ nanosheets. Scanning transmission electron microscopy (STEM) analyses confirmed the existence of an effective interface between a g-C₃N₄ nanosheet and a TiO₂ nanocrystal. X-ray photoelectron spectroscopy (XPS) evidenced no chemical alterations to both g-C₃N₄ and TiO₂ at the heterostructure. The visible-light absorption shift was indicated by the red shift in the absorption onset through the ultraviolet-visible (UV-VIS) absorption spectra. The 30 wt. % of g-C₃N₄/TiO₂ heterostructure showed the best photocatalytic performance, with a MO dye degradation of 85% in 4 h, corresponding to an enhanced efficiency of almost 2 and 10 times greater than that of pure TiO₂ and g-C₃N₄ nanosheets, respectively. Superoxide radical species were found to be the most active radical species in the MO photodegradation process. The creation of a type-II heterostructure is highly suggested due to the negligible participation of hydroxyl radical species in the photodegradation process. The superior photocatalytic activity was attributed to the synergy of g-C₃N₄ and TiO₂ materials.