Preparation of Fe3O4 encapsulated-silica sulfonic acid nanoparticles and study of their in vitro antimicrobial activity

Revolutionizing microorganism inactivation: Magnetic nanomaterials in sustainable photocatalytic disinfection

The rapid emergence of antibiotic-resistant microorganisms and the demand for sustainable water purification methods have spurred research into advanced disinfection, with photocatalysis as a promising approach. This study explores magnetic nanomaterials as catalysts in photocatalytic processes for microorganism inactivation. Magnetic nanoparticles and composites, due to their unique properties, are promising for enhancing photocatalytic disinfection. Their inherent magnetic traits enable easy separation and recyclability, reducing operational costs and environmental impact. These materials also act as efficient electron transfer mediators, enhancing overall photocatalytic efficiency. The review covers the synthesis and characterization of magnetic nanomaterials for photocatalytic applications, focusing on their structural, magnetic, and surface properties. Photocatalytic mechanisms, including reactive oxygen species (ROS) generation vital for microorganism inactivation, are discussed. The study examines combining common photocatalysts like TiO2, ZnO, and semiconductors with magnetic nanomaterials, highlighting synergistic effects. Recent advances and challenges, such as optimal nanomaterials selection and scalability for large-scale applications, are addressed. Case studies and experimental setups for microorganism inactivation underscore the potential of magnetic nanomaterials in water treatment, air purification, and medical disinfection. Finally, further research directions and research highlights the substantial potential of magnetic nanomaterials as catalysts in photocatalytic processes, offering an efficient and sustainable solution for microorganism inactivation and contributing valuable insights to environmental and public health advancement.

Green synthesis of iron nanoparticles: Sources and multifarious biotechnological applications

Green synthesis of iron nanoparticles is a highly fascinating research area and has gained importance due to reliable, sustainable and ecofriendly protocol for synthesizing nanoparticles, along with the easy availability of plant materials and their pharmacological significance. As an alternate to physical and chemical synthesis, the biological materials, like microorganisms and plants are considered to be less costly and environment-friendly. Iron nanoparticles with diverse morphology and size have been synthesized using biological extracts. Microbial (bacteria, fungi, algae etc.) and plant extracts have been employed in green synthesis of iron nanoparticles due to the presence of various metabolites and biomolecules. Physical and biochemical properties of biologically synthesized iron nanoparticles are superior to that are synthesized using physical and chemical agents. Iron nanoparticles have magnetic property with thermal and electrical conductivity. Iron nanoparticles below a certain size (generally 10-20 nm), can exhibit a unique form of magnetism called superparamagnetism. They are non-toxic and highly dispersible with targeted delivery, which are suitable for efficient drug delivery to the target. Green synthesized iron nanoparticles have been explored for multifarious biotechnological applications. These iron nanoparticles exhibited antimicrobial and anticancerous properties. Iron nanoparticles adversely affect the cell viability, division and metabolic activity. Iron nanoparticles have been used in the purification and immobilization of various enzymes/proteins. Iron nanoparticles have shown potential in bioremediation of various organic and inorganic pollutants. This review describes various biological sources used in the green synthesis of iron nanoparticles and their potential applications in biotechnology, diagnostics and mitigation of environmental pollutants.

Synthesis and validation of ultrasensitive stripping voltammetric sensor based on polypyrrole@ZnO/Fe3O4 core-shell nanostructure for picomolar detection of artesunate and dopamine drugs

A stripping voltammetric sensor for ultrasensitive detection of artesunate (ART) and dopamine HCl (DA) has been successfully developed using a Ppy@ZnO/Fe₃O₄ core-shell nanocomposite ([PZM])-modified carbon paste sensor (MCPS). Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, dynamic light scattering, Brunauer-Emmett-Teller surface area method, and high-resolution transmission electron microscopy were used to characterize the physicochemical properties of the nanomaterials. Noteworthily, the morphology of [PZM] reveals a spherical core-shell nanostructure with an increase in the average diameter range of 20-37.5 nm (specific surface area (SSA) of 28.5 m² g^-1 (0.0247 cm³ g^-1)) when compared with the average diameter range 7.5-15.7 nm (SSA of 5.43 m² g^-1 (0.0111 cm³ g^-1)) of ZnO/Fe₃O₄[ZM]. The [PZM] MCPS provided the best electroactive surface area (0.078 cm²) and the least electrocatalytic activity (R_st = 370 Ω). Furthermore, the MCPS showed low detection limits (LODs) of 0.092 pg mL^-1 (0.24 pM) and 0.0046 pg mL^-1 (0.03 pM) for ART and DA, respectively. Moreover, LODs were found to be 0.029 pg mL^-1 (0.75 pM) and 0.014 pg mL^-1 (0.09 pM) for ART mixed with 0.7 pM of DA (ART₁) and DA in the presence of 2.0 pM of ART drug (DA₁), respectively. In addition, the MCPS revealed a proper repeatability, reproducibility, and storage stability (93.5-90.48%). During the routine analysis, the [PZM] MCPS detected ART and DA concentrations in human urine, without interference.

Attachment of Tragacanth gum on polyester fabric through the synthesis of iron oxide gaining novel biological, physical, and thermal features

This study focuses on polyester fabric modification to produce environmentally-friendly multifunctional fabrics for varied applications. The nanoparticles of iron oxide were achieved from ferrous sulfate solution under alkaline conditions and applied to Tragacanth gum to form an efficient layer on the polyester surface. The synthesis of Fe₃O₄ nanoparticles with a crystal size of 12 nm was approved in the XRD spectra and iron oxide/Tragacanth gum nanocomposites with an agglomerated size of about 62 nm were confirmed by the SEM and EDX techniques. The formation of hydroxyl and iron oxide bands was observed in the FTIR and XPS patterns. The superparamagnetic behavior of treated samples exhibited by VSM with a magnetic saturation of 0.86 emu/g. The products showed an antibacterial activity (95 and 91%) toward Gram-positive and -negative bacteria. The absorbance intensity of methylene blue decreased from 2.6 to 1.6 by the treated sample. The synthesized nanoparticles on the treated surface indicated a lower release of iron ions and cell toxicity. The rate of cell duplication increased under a magnetic field with 60 Hz and 0.5 mT for 20 min/day. The product color changed from white to a brownish hue and the wetting capacity and thermal ability increased.

Synthesis and Characterization of Novel Fe3O4/PVA/Eggshell Hybrid Nanocomposite for Photodegradation and Antibacterial Activity

In the 21st century, hybrid nanocomposites were widely used in bioelectronic, biosensing, photocatalytic, and biomedical applications. In the present study, we fabricated a novel Fe3O4/PVA/Eggshell hybrid nanocomposite and physicochemically characterized it using powder XRD, EDS, FTIR, VSM, and HR-TEM analysis. The XRD spectrum revealed the crystalline and FCC configuration of Fe3O4 NPs with average crystal size of 16.28 nm, and the HRTEM image indicates the prepared hybrid nanocomposite is of spherical shape with less agglomeration. This hybrid nanocomposite showed a significant photodegradation property in degrading organic pollutants such as congo red and crystal violet dyes under the sunlight irradiation. In addition, the hybrid nanocomposite also displayed a potent antibacterial property against different Gram +ve and Gram −ve bacterial pathogens. This study provides a significant example in the overview of fabrication of cost effectively, eco-friendly, and multiple-application hybrid nanocomposites through eggshell membrane fibers.

Do Iron Oxide Nanoparticles Have Significant Antibacterial Properties?

The use of metal oxide nanoparticles is one of the promising ways for overcoming antibiotic resistance in bacteria. Iron oxide nanoparticles (IONPs) have found wide applications in different fields of biomedicine. Several studies have suggested using the antimicrobial potential of IONPs. Iron is one of the key microelements and plays an important role in the function of living systems of different hierarchies. Iron abundance and its physiological functions bring into question the ability of iron compounds at the same concentrations, on the one hand, to inhibit the microbial growth and, on the other hand, to positively affect mammalian cells. At present, multiple studies have been published that show the antimicrobial effect of IONPs against Gram-negative and Gram-positive bacteria and fungi. Several studies have established that IONPs have a low toxicity to eukaryotic cells. It gives hope that IONPs can be considered potential antimicrobial agents of the new generation that combine antimicrobial action and high biocompatibility with the human body. This review is intended to inform readers about the available data on the antimicrobial properties of IONPs, a range of susceptible bacteria, mechanisms of the antibacterial action, dependence of the antibacterial action of IONPs on the method for synthesis, and the biocompatibility of IONPs with eukaryotic cells and tissues.

Do Iron Oxide Nanoparticles Have Significant Antibacterial Properties?

The use of metal oxide nanoparticles is one of the promising ways for overcoming antibiotic resistance in bacteria. Iron oxide nanoparticles (IONPs) have found wide applications in different fields of biomedicine. Several studies have suggested using the antimicrobial potential of IONPs. Iron is one of the key microelements and plays an important role in the function of living systems of different hierarchies. Iron abundance and its physiological functions bring into question the ability of iron compounds at the same concentrations, on the one hand, to inhibit the microbial growth and, on the other hand, to positively affect mammalian cells. At present, multiple studies have been published that show the antimicrobial effect of IONPs against Gram-negative and Gram-positive bacteria and fungi. Several studies have established that IONPs have a low toxicity to eukaryotic cells. It gives hope that IONPs can be considered potential antimicrobial agents of the new generation that combine antimicrobial action and high biocompatibility with the human body. This review is intended to inform readers about the available data on the antimicrobial properties of IONPs, a range of susceptible bacteria, mechanisms of the antibacterial action, dependence of the antibacterial action of IONPs on the method for synthesis, and the biocompatibility of IONPs with eukaryotic cells and tissues.

Fabrication of Zn-based magnetic zeolitic imidazolate framework bionanocomposite using basil seed mucilage for removal of azo cationic and anionic dyes from aqueous solution

The Basil seeds mucilaginous polysaccharide exhibits remarkable physical and chemical properties like high water-absorbing capacity, emulsifying, and stabilizing properties. The metal-organic frameworks are one of the most promising precursors made of metal clusters and organic connectors for the fabrication of advanced adsorbents due to their unique properties. In this study, the bionanocomposite of magnetic zeolitic imidazolate framework-8 was successfully synthesized and applied to adsorb azo cationic and anionic dyes. The synthesized magnetite nanoparticles were pretreated with mucilage extracted from basil seeds to acquire negatively charged magnetite surface, followed by nucleation through attracting zinc cation, and then the growth of metal-organic frameworks which yields high-quality ZIF-8 crystals. The samples were characterized by Field Scanning Electron Microscopy, X-ray Diffraction, Fourier Transform Infrared Spectrometry, vibrating sample magnetometer, and Brunauer-Emmett-Teller surface area analysis. In the process of adsorption, influencing factors and recycling regeneration were discussed, and the adsorption mechanisms such as kinetics, isotherm, and thermodynamics were explored. The results of the adsorption process showed that maximum adsorption capacities were 9.09 and 13.21 mg/g for Methylene blue and Eriochrome Black T, respectively. The excellent reusability combined with its magnetic separation property makes the nanocomposite a promising adsorbent for the removal of cationic and anionic dyes.

Magnetic Nanoparticles of Fe3O4 Biosynthesized by Cnicus benedictus Extract: Photocatalytic Study of Organic Dye Degradation and Antibacterial Behavior

Currently, the use of sustainable chemistry as an ecological alternative for the generation of products or processes that are free of a polluting substance has assumed a preponderant role. The aim of this work is to propose a bioinspired, facile, low cost, non-toxic, and environmentally friendly alternative to obtaining magnetic nanoparticles with a majority phase of magnetite (Fe3O4). It is important to emphasize that the synthesis was based on the chemical reduction through the Cnicus benedictus extract, whose use as reducing agent has not been reported in the synthesis of iron oxides nanoparticles. In addition, the Cnicus benedictus is an abundant endemic plant in Mexico with several medicinal properties and a large number of natural antioxidants. The obtained nanoparticles exhibited significant magnetic and antibacterial properties and an enhanced photocatalytic activity. The crystallite size of the Fe3O4 nanoparticles (Fe3O4 NP’s) was calculated by the Williamson-Hall method. The photocatalytic properties of the Fe3O4 NP’s were studied by kinetics absorptions models in the Congo red (CR) degradation. Finally, the antibacterial effects of the Fe3O4 NPs were evaluated mediated the Kirby–Bauer method against Escherichia coli and Staphylococcus aureus bacteria. This route offers a green alternative to obtain Fe3O4 NPs with remarkable magnetic, photocatalytic, and antibacterial properties.

Magnetic Nano-Sized Solid Acid Catalyst Bearing Sulfonic Acid Groups for Biodiesel Synthesis

In our approach for magnetic iron oxide nanoparticles surface modification, the fabrication of an inorganic shell, consisting of silica by the deposition of preformed colloids onto the nanoparticle surface and functionalization of these particles, was realized. The magnetic nanoparticles, non-coated and coated with silica layer by Stöber method, are functionalized with chlorosulfonic acid. The magnetic nanoparticles (MNPs), in size of 10-13 nm, could be used as acid catalyst in biodiesel production and show superparamagnetic character. The prepared nanoparticles were characterized by different methods including XRD, EDX, FT-IR and VSM. The catalytic activity of the coated and non-coated solid acids was examined in palmitic acid-methanol esterification as an industrial reaction for biodiesel synthesis. Although thin silica layer results in only a minor obstacle with respect to magnetism, it can accelerate the mass transportation due to its relatively porous structure and magnetic core may be more stable in the acidic reaction medium by means of covering process. Accordingly, coating strategy can be efficient way for allowing applications of MNPs in acid catalyzed esterification.

Preparation and electrochemical properties of cobalt-phthalocyanine-decorated Fe3O4 nanoparticles

Phthalocyanines (Pcs) have been known for excellent electron transfer properties owing to their extended [Formula: see text]-conjugated structures. In addition, functionalized iron oxide nanoparticles (Fe[Formula: see text]O[Formula: see text] NPs) have attracted considerable interest owing to their unique spectral and electronic properties. Hence, it can be reasonably expected that Fe[Formula: see text]O[Formula: see text] NPs decorated with Pc molecules could provide a useful electrocatalytic system. Herein, we present the preparation and electrochemical properties of cobalt-phthalocyanine (CoPc)-decorated Fe[Formula: see text]O[Formula: see text] NPs (CoPc@Fe[Formula: see text]O[Formula: see text]. The Fe[Formula: see text]O[Formula: see text] NPs were first coated with a silica layer to produce SiO[Formula: see text]@Fe[Formula: see text]O[Formula: see text]. Subsequently, CoPc with a siloxane end group (CoPc-TEOS) was anchored to the outer surface of the SiO[Formula: see text]@Fe[Formula: see text]O[Formula: see text]. The CoPc@Fe[Formula: see text]O[Formula: see text] thus prepared was fully analyzed using various characterization methods. Distinctive electrochemical responses of CoPc and CoPc@Fe[Formula: see text]O[Formula: see text] in the presence of picric acid were observed, demonstrating the potential application of the current approach to electrochemical catalysis.

Green synthesis of magnetic Fe3O4 nanoparticles using Couroupita guianensis Aubl. fruit extract for their antibacterial and cytotoxicity activities

In the present study, a sustainable green chemistry approach was established to fabricate magnetic Fe₃O₄ nanoparticles (Fe₃O₄NPs) using the aqueous fruit extract of edible C. guianensis (CGFE). Synthesized NPs were further confirmed with different high-throughput characterization techniques such as UV-visible spectroscopy, FT-IR, XPS, DLS and zeta potential analysis. Additionally, XRD, AFM, HRTEM and SQUID VSM demonstrate the generation of crystalline CGFe₃O₄NPs with mean diameter of 17 ± 10 nm. Interestingly, CGFe₃O₄NPs exhibit a stupendous bactericidal action against different human pathogens which depicts its antimicrobial value. A significant dose-dependent cytotoxic effect of CGFe₃O₄NPs was noticed against treated human hepatocellular carcinoma cells (HepG2).

Metal oxide nanoparticles as antimicrobial agents: a promise for the future

Microbial infectious diseases are a global threat to human health. Excess and improper use of antibiotics has created antimicrobial-resistant microbes that can defy clinical treatment. The hunt for safe and alternate antimicrobial agents is on in order to overcome such resistant micro-organisms, and the birth of nanotechnology offers promise to combat infectious organisms. Over the past two decades, metal oxide nanoparticles (MeO-NPs) have become an attractive alternative source to combat microbes that are highly resistant to various classes of antibiotics. Their vast array of physicochemical properties enables MeO-NPs to act as antimicrobial agents through various mechanisms. Apart from exhibiting antimicrobial properties, MeO-NPs also serve as carriers of drugs, thus barely providing a chance for micro-organisms to develop resistance. These immense multiple properties exhibited by MeO-NPs will have an impact on the treatment of deadly infectious diseases. This review discusses the mechanisms of action of MeO-NPs against micro-organisms, safety concerns, challenges and future perspectives.