Mn3O4 nanoparticles: Synthesis, characterization and their antimicrobial and anticancer activity against A549 and MCF-7 cell lines

Plant-mediated synthesis of Mn3O4nanoparticles: challenges and applications

This review focuses on the green synthesis methods, challenges, and applications of manganese oxide (Mn3O4) nanoparticles investigated in the past five years. Mn3O4nanoparticles offer some unique properties that are attributed in part to the presence of mixed oxidation states of manganese (i.e. +2 and +3) in the particle, which can be utilized in a wide range of redox-sensitive applications, such as in developing supercapacitive energy storage materials. In addition, the green synthesis of Mn3O4nanoparticles through plant extracts has potential uses in sustainable nanotechnology. Various plant extract-mediated synthesis techniques for Mn3O4nanoparticles have been investigated and presented. By comparing the size and structure of the synthesized Mn3O4nanoparticles, we have observed a consistent pattern of obtaining spherical particles with a size ranging from 16 to 50 nm. The morphology of the generated Mn3O4nanoparticles can be influenced by the annealing temperature and the composition of the plant extract used during the nanoparticle synthesis. Additionally, numerous applications for the greenly produced Mn3O4nanoparticles have been demonstrated. Mn3O4nanoparticles derived from plant extracts have been found to possess antimicrobial properties, supercapacitive and electrochemical capabilities, and excellent pollutant degradation efficiency. However, the magnetic properties of these nanoparticles synthesized by plant extracts are yet to be explored for potential biomedical applications. Finally, challenges to existing synthetic methods and future perspectives on the potential applications of these green synthesized Mn3O4nanoparticles are highlighted.

Work Function Tuning of Carbon Electrode to Boost the Charge Extraction in Hole Transport Layer-Free Perovskite Solar Cells

Perovskite solar cell (PSC) is a promising photovoltaic technology that achieves over 26% power conversion efficiency (PCE). However, the high materials costs, complicated fabrication process, as well as poor long-term stability, are stumbling blocks for the commercialization of the PSCs in normal structures. The hole transport layer (HTL)-free carbon-based PSCs (C-PSCs) are expected to overcome these challenges. However, C-PSCs have suffered from relatively low PCE due to severe energy loss at the perovskite/carbon interface. Herein, the study proposes to boost the hole extraction capability of carbon electrode by incorporating functional manganese (II III) oxide (Mn3O4). It is found that the work function (WF) of the carbon electrode can be finely tuned with different amounts of Mn3O4 addition, thus the interfacial charge transfer efficiency can be maximized. Besides, the mechanical properties of carbon electrode can also be strengthened. Finally, a PCE of 19.03% is achieved. Moreover, the device retains 90% of its initial PCE after 2000 h of storage. This study offers a feasible strategy for fabricating efficient paintable HTL-free C-PSCs.

Manganese Nanoparticles: Synthesis, Mechanisms of Influence on Plant Resistance to Stress, and Prospects for Application in Agricultural Chemistry

Manganese (Mn) is an important microelement for the mineral nutrition of plants, but it is not effectively absorbed from the soil and mineral salts added thereto and can also be toxic in high concentrations. Mn nanoparticles (NPs) are less toxic, more effective, and economical than Mn salts due to their nanosize. This article critically reviews the current publications on Mn NPs, focusing on their effects on plant health, growth, and stress tolerance, and explaining possible mechanisms of their effects. This review also provides basic information and examples of chemical, physical, and ecological ("green") methods for the synthesis of Mn NPs. It has been shown that the protective effect of Mn NPs is associated with their antioxidant activity, activation of systemic acquired resistance (SAR), and pronounced antimicrobial activity against phytopathogens. In conclusion, Mn NPs are promising agents for agriculture, but their effects on gene expression and plant microbiome require further research.

Plant mediated biosynthesis of Mn3O4 nanostructures and their biomedical applications

Nanomaterials have drawn significant attention for their biomedical and pharmaceutical applications. In the present study, manganese tetra oxide (Mn3O4) nanoparticles were prepared greenly, and their physicochemical properties were studied. Taxus baccata acetone extract was used as a safely novel precursor for reducing and stabilizing nanoparticles. The synthesized nanoparticles were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), Brunauer-Emmett-Teller (BET), and Barrett-Joyner-Halenda (BJH) and X-ray diffraction (XRD). The cytotoxicity of Mn3O4 (hausmannite) nanostructures was evaluated against murine macrophage cell line J774-A1 and U87 glioblastoma cancer cells for approximately 72 h. Spherical Mn3O4 nanoparticles with tetragonal spinel structures demonstrated minimal toxicity against normal body cells with CC50 around 876.38 μg mL-1. Moreover, Mn3O4 nanoparticles as well as the combination of antimoniate meglumine and Mn3O4 nanoparticles exhibited maximum mortality in Leishmania major. The synthesized nanominerals displayed a significant inhibitory effect against glioblastoma cancer cells at 100 μg mL-1. The selective cytotoxicity of Mn3O4 nanoparticles indicates that these biogenic agents can be employed simultaneously for diagnostic and therapeutic applications in medical applications.

Characterization of Mn3 O4 -MnO2 nanocomposites biosynthesized by cell lysate of Haloferax alexandrinus GUSF-1

Manganese oxide nanocomposites attract huge attention in various biotechnological fields due to their extensive catalytic properties. This study reports an easy, rapid, and cost-effective method of using the cell lysate of haloarchaeon, Haloferax alexandrinus GUSF-1 for the synthesis of manganese oxide nanoparticles. The reaction between the cell lysate and manganese sulfate resulted in the formation of a dark brown precipitate within 48 h at room temperature. The X-ray diffraction pattern showed the existence of Mn3 O4 and MnO2 phases consistent with the JCPDS card no. (01-075-1560 and 00-050-0866). The dark brown colloidal suspension of MnO3 -MnO2 in methanol showed maximum absorption between 220 and 260 nm. The EDX spectrum confirmed the presence of manganese and oxygen. The Transmission electron microscopy revealed the spherical morphology with an average particle size between 30 and 60 nm. The magnetic moment versus magnetic field (MH) curve, at room temperature (300 K) did not saturate even at a high magnetic field (±3T) indicating the paramagnetic nature of the prepared nanocomposite. The Atomic Emission Spectroscopic analysis showed a negligible amount of soluble manganese (0.03 ppm in 50 ppm) in the Mn3 O4 -MnO2 suspension suggesting the maximum stability of the material in the solvent over time. Interstingly, Mn3 O4 -MnO2 nanocomposites evidenced antimicrobial activity in the order of Pseudomonas aeruginosa > Salmonella typhi > Escherichia coli > Proteus vulgaris > Candida albicans > Staphylococcus aureus. Conclusively, this is the first report on the formation of Mn3 O4 -MnO2 nanocomposites using cell lysate of salt pan haloarcheon Haloferax alexandrinus GUSF-1 with antimicrobial potential.

Surface Modification of Titanium Implants by Metal Ions and Nanoparticles for Biomedical Application

Implant surface modification can improve osseointegration and reduce peri-implant inflammation. Implant surfaces are modified with metals because of their excellent mechanical properties and significant functions. Metal surface modification is divided into metal ions and nanoparticle surface modification. These two methods function by adding a finishing metal to the surface of the implant, and both play a role in promoting osteogenic, angiogenic, and antibacterial properties. Based on this, the nanostructural surface changes confer stronger antibacterial and cellular affinity to the implant surface. The current paper reviews the forms, mechanisms, and applications of nanoparticles and metal ion modifications to provide a foundation for the surface modification of implants.

Effective Removal of Methylene Blue by Mn3O4/NiO Nanocomposite under Visible Light

Wastewater treatment is indispensable as wastewater can lead to adverse health effects and deteriorate the quality of life on earth. Photocatalysis is a facile methodology to address this issue. In this study, nanocomposites (NCs) of manganese oxide (Mn3O4) and nickel oxide (NiO) were synthesized in different weight ratios via the solid-state reaction route. Structural properties, optical properties, surface morphology, and functional group analysis of the synthesized nanomaterials were conducted using X-ray diffraction (XRD), UV– Vis spectroscopy, scanning electron microscopy (SEM) along with energy-dispersive X-ray (EDX) analysis, and Fourier-transform infrared (FTIR) spectroscopy, respectively. The bandgap of the nanocomposite decreases significantly from 2.35 eV for the Mn3O4 NPs to 1.65 eV for the Mn3O4/NiO nanocomposite (NC). Moreover, adsorption studies followed by the photocatalytic performance of the Mn3O4/NiO NCs were evaluated to determine the removal of methylene blue (MB) dye from wastewater. The photocatalytic performance of the nanocomposite enhances as the ratio of Mn3O4 in the composite increases from one weight percentage to three weight percentage. The photocatalytic degradation efficiency was calculated to be 95%. The results show that the synthesized NCs could play an important role in photocatalytic wastewater purification and environmental remediation.

Facile Green Synthesis of Ni(OH)2@Mn3O4 Cactus-Type Nanocomposite: Characterization and Cytotoxicity Properties

In the present work, the facile eco-friendly synthesis and evaluation of the anti-tumor activity of Ni(OH)₂@Mn₃O₄ nanocomposite were carried out. The synthesis of Ni(OH)₂@Mn₃O₄ nanocomposite from chia-seed extract was mediated by sonication. The obtained materials were characterized by different spectroscopic techniques such as transmission electron microscopy (TEM), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible (UV-Vis), and Fourier transform infrared (FT-IR) spectroscopies. The results of XRD, SEM, EDS, TEM, FT-IR, and UV-Vis analysis indicate the successful manufacturing of a crystalline, cactus-type Ni(OH)₂@Mn₃O₄ nanocomposite of 10.10 nm average particle size. XPS analysis confirms that the synthesized materials consist mainly of Ni²⁺, Mn²⁺, and Mn³⁺. The antitumor activity of the nanocomposite was tested against a breast cancer (MCF-7) cell line. The results showed Ni(OH)₂@Mn₃O₄ nanocomposite possesses insignificant cytotoxicity. The cell-death percentage was 34% at a 100 ppm concentration of Ni(OH)₂@Mn₃O₄ nanocomposite. The obtained results imply that the synthesized nanocomposite could be suitable and safe for drug delivery and water treatment.

Toxicology assessment of manganese oxide nanomaterials with enhanced electrochemical properties using human in vitro models representing different exposure routes

In the present study, a comparative human toxicity assessment between newly developed Mn₃O₄ nanoparticles with enhanced electrochemical properties (GNA35) and their precursor material (Mn₃O₄) was performed, employing different in vitro cellular models representing main exposure routes (inhalation, intestinal and dermal contact), namely the human alveolar carcinoma epithelial cell line (A549), the human colorectal adenocarcinoma cell line (HT29), and the reconstructed 3D human epidermal model EpiDerm. The obtained results showed that Mn₃O₄ and GNA35 harbour similar morphological characteristics, whereas differences were observed in relation to their surface area and electrochemical properties. In regard to their toxicological properties, both nanomaterials induced ROS in the A549 and HT29 cell lines, while cell viability reduction was only observed in the A549 cells. Concerning their skin irritation potential, the studied nanomaterials did not cause a reduction of the skin tissue viability in the test conditions nor interleukin 1 alpha (IL- 1 α) release. Therefore, they can be considered as not irritant nanomaterials according to EU and Globally Harmonized System of Classification and Labelling Chemicals. Our findings provide new insights about the potential harmful effects of Mn₃O₄ nanomaterials with different properties, demonstrating that the hazard assessment using different human in vitro models is a critical aspect to increase the knowledge on their potential impact upon different exposure routes.

Ferrous Industrial Wastes-Valuable Resources for Water and Wastewater Decontamination

Ferrous waste by-products from the metallurgical industry have a high potential for valorization in the context of the circular economy, and can be converted to value-added products used in environmental remediation. This research reviews the latest data available in the literature with a focus on: (i) sources from which these types of iron-based wastes originate; (ii) the types of ferrous compounds that result from different industries; (iii) the different methods (with respect to the circular economy) used to convert them into products applied in water and wastewater decontamination; (iv) the harmful effects ferrous wastes can have on the environment and human health; and (v) the future perspectives for these types of waste.

Anti-breast Adenocarcinoma and Anti-urease Anti-tyrosinase Properties of 5-Pentylresorcinol as Natural Compound with Molecular Docking Studies

5-Pentylresorcinol is a type of the group of resorcinol compounds that is resorcinol in that has hydrogen atom at position 5 is replaced by a pentyl group. It has a role as a lichen metabolite. This compound showed excellent to good inhibitory activities against studied these enzymes with IC₅₀ values of 65.96 µM for urease and 34.81 µM for tyrosinase. Standard compounds for enzymes had IC₅₀ values of 1.94±0.24 µM against urease and 84.36±5.17 µM against tyrosinase. The IC₅₀ of 5-pentylresorcinol against MCF7 cell line was 165.72 µg/mL; against Hs 578Bst cell line was 102.14 µg/mL; against Hs 319.T cell line was 12.34 µg/mL; and against UACC-3133 cell line was 73.07 µg/mL, respectively. The chemical activities of 5-pentylresorcinol against urease and tyrosinase were evaluated using the molecular modeling study. The anti-cancer activity of 5-pentylresorcinol was also investigated by treating the compound on the BRCT repeat region from the breast cancer-associated protein (BRCA1), and their interactions were assessed utilizing the molecular docking calculations. The results revealed the probable interactions and their characteristics at an atomic level. The docking scores of 5-pentylresorcinol against urease, tyrosinase, and BRCA1 are -3.073, -5.262, and -3.238 (kcal/mol), respectively.

Current Strategies and Potential Prospects for Nanoparticle-Mediated Treatment of Diabetic Nephropathy

Diabetic nephropathy (DN), a severe microvascular complication of diabetes mellitus (DM), is the most common form of chronic kidney disease (CKD) and a leading cause of renal failure in end-stage renal disease. No currently available treatment can achieve complete cure. Traditional treatments have many limitations, such as painful subcutaneous insulin injections, nephrotoxicity and hepatotoxicity with oral medication, and poor patient compliance with continual medication intake. Given the known drawbacks, recent research has suggested that nanoparticle-based drug delivery platforms as therapeutics may provide a promising strategy for treating debilitating diseases such as DN in the future. This administration method provides multiple advantages, such as delivering the loaded drug to the precise target of action and enabling early prevention of CKD progression. This article discusses the development of the main currently used nanoplatforms, such as liposomes, polymeric NPs, and inorganic NPs, as well as the prospects and drawbacks of nanoplatform application in the treatment of CKD.