Gallium Nanoparticles Research Articles

Immobilization of biosynthesized gallium nanoparticles in Polyvinylpyrrolidone/Sodium alginate films: Potent bactericidal protection against food spoilage bacteria

The increasing threat of spoilage bacterial infections, driven by the resistance of bacteria to many antimicrobial treatments, is a significant worldwide public health problem, especially concerning food preservation. To tackle these difficulties, this research investigates the possibility of using packaging sheets that include antimicrobial agents and increasing the prolonged storage time by preventing the bioburden of foodborne pathogens. This approach uses metal nanoparticles' ability to prevent harmful bacteria that cause food spoiling. Gallium nanoparticles (GaNPs) were created using a water-based extract from Andrographis paniculata leaves as a bioreducing agent. The GaNPs were added to a film made of sodium alginate (SA) and polyvinylpyrrolidone (PVP). The study showed that incorporating GaNPs into polymer films resulted in films with a desirable contact angle and decreased water vapor permeability. Significantly, the developed films demonstrated increased efficiency against E.coli O157 compared to other species. Also, it exhibited increased vulnerability to bacterial strains at the biofilm stage, surpassing PVP-SA/GaNPs-0. Remarkably, the toxicity tests showed that the films exhibited no cytotoxicity. Overall, the films indicated their potential for avoiding bacterial bioburden, prolonging the shelf life of perishable products, and contributing to diverse antimicrobial applications in the food industry.

Nanogallium-poly(L-lactide) Composites with Contact Antibacterial Action.

In diverse biomedical and other applications of polylactide (PLA), its bacterial contamination and colonization are unwanted. For this reason, this biodegradable polymer is often combined with antibacterial agents or fillers. Here, we present a new solution of this kind. Through the process of simple solvent casting, we developed homogeneous composite films from 28 ± 5 nm oleic-acid-capped gallium nanoparticles (Ga NPs) and poly(L-lactide) and characterized their detailed morphology, crystallinity, aqueous wettability, optical and thermal properties. The addition of Ga NPs decreased the ultraviolet transparency of the films, increased their hydrophobicity, and enhanced the PLA structural ordering during solvent casting. Albeit, above the glass transition, there is an interplay of heterogeneous nucleation and retarded chain mobility through interfacial interactions. The gallium content varied from 0.08 to 2.4 weight %, and films with at least 0.8% Ga inhibited the growth of Pseudomonas aeruginosa PAO1 in contact, while 2.4% Ga enhanced the effect of the films to be bactericidal. This contact action was a result of unwrapping the top film layer under biological conditions and the consequent bacterial contact with the exposed Ga NPs on the surface. All the tested films showed good cytocompatibility with human HaCaT keratinocytes and enabled the adhesion and growth of these skin cells on their surfaces when coated with poly(L-lysine). These properties make the nanogallium-polyl(L-lactide) composite a promising new polymer-based material worthy of further investigation and development for biomedical and pharmaceutical applications.

Melatonin-loaded mesoporous zinc- and gallium-doped hydroxyapatite nanoparticles to control infection and bone repair.

Effective treatment of infected bone defects resulting from multi-drug resistant bacteria (MDR) has emerged as a significant clinical challenge, highlighting the pressing demand for potent antibacterial bone graft substitutes. Mesoporous nanoparticles have been introduced as a promising class of biomaterials offering significant properties for treating bone infections. Herein, we synthesize antibacterial mesoporous hydroxyapatite substituted with zinc and gallium (Zn-Ga:mHA) nanoparticles using a facile sol-gel method. The resulting mesoporous nanoparticles are applied for the controlled release of melatonin (Mel). Zn-Ga:mHA nanoparticles with an average particle size of 36 ± 3 nm and pore size of 10.6 ± 0.4 nm reveal a Mel loading efficiency of 58 ± 1%. Results show that 50% of Mel is released within 20 h and its long-term release is recorded up to 50 h. The Zn-Ga:mHA nanoparticles exhibit highly effective antibacterial performance as reflected by a 19 ± 1% and 8 ± 2% viability reduction in Escherichia coli and Staphylococcus bacteria, respectively. Noticeably, Mel-loaded Zn-Ga:mHA nanoparticles are also cytocompatible and stimulate in vitro osteogenic differentiation of human mesenchymal stem cells (hMSCs) without any osteoinductive factor. In vivo studies in a rabbit skull also show significant regeneration of bone during 14 days. In summary, Mel-loaded Zn-Ga:mHA nanoparticles provide great potential as an antibacterial and osteogenic component in bone substitutes like hydrogels, scaffolds, and coatings.

Sculpting liquid metal stabilized interfaces: a gateway to liquid electronics.

Liquid electronics have potential applications in soft robotics, printed electronics, and healable electronics. The intrinsic shortcomings of solid-state electronics can be offset by liquid conductors. Alloys of gallium have emerged as transformative materials for liquid electronics owing to their intrinsic fluidity, conductivity, and low toxicity. However, sculpting liquid metal or its composites into a 3D architecture is a challenging task. To tackle this issue, herein, we explored the interfacial chemistry of metal ions and tannic acid (TA) complexation at a liquid-liquid interface. First, we established that an MIII-TA network at the liquid-liquid interface could structure liquid in liquid by jamming the interfacial film. The surface coverage of the droplet largely depends on the concentration of metal ions, oxidation state of metal ions and pH of the surrounding environment. Further extending the approach, we demonstrated that TA-functionalized gallium nanoparticles (Ga NPs) can also sculpt liquid droplets in the presence of transition metal ions. Finally, a mold-based free-standing 3D architecture is obtained using the interfacial reaction and interfacial crowding of a metal-phenolate network. Conductivity measurement reveals that these liquid constructs can be used for low-voltage electronic applications, thus opening the door for liquid electronics.

Gallium nanoparticles as antireflection structures on III-V solar cells

The integration of nanostructures on top of solar cells has been previously demonstrated as an effective method to increase the collection efficiency by coupling to sunlight. In this work, this approach is implemented by using core-shell gallium nanoparticles (Ga-NPs) as functional light scatterers on III-V solar cells, investigating how the Ga-NPs affect their photovoltaic performance. The effect is studied in GaAs and in GaAsSbN superlattice-based solar cells with different bandgaps for a wide range of Ga-NPs sizes. After NP size optimization, average improvements in the short-circuit current around 18 % are obtained in both types of solar cells with these nanostructures. The underlying physical mechanism is studied by performing optical measurements and simulations. It is found that the Ga-NPs can be treated as an antireflection coating due to both their geometry and the refractive index in the cases when their localized surface plasmon resonances do not spectrally overlap with the solar cell absorption range. Lastly, a facile method to attenuate the plasmonic effect of the Ga-NPs it is also shown as a proof of concept. In this method, an annealing treatment at low temperature is performed causing an improvement of the photovoltaic performance. This work demonstrates that Ga-NPs can successfully enhance the efficiency of III-V solar cells in a very controllable manner and paves the way for the design of new functional nanostructures.

Gallium Nanoparticle Formation and Doping of Nanocrystalline Alumina from a Ga–Al Liquid Metal Hydrogen Generating Reaction

Gallium Nanoparticle Formation and Doping of Nanocrystalline Alumina from a Ga–Al Liquid Metal Hydrogen Generating Reaction

Gallium Liquid Metal: Nanotoolbox for Antimicrobial Applications.

The proliferation of drug resistance in microbial pathogens poses a significant threat to human health. Hence, treatment measures are essential to surmount this growing problem. In this context, liquid metal nanoparticles are promising. Gallium, a post-transition metal notable for being a liquid at physiological temperature, has drawn attention for its distinctive properties, high antimicrobial efficacy, and low toxicity. Moreover, gallium nanoparticles demonstrate anti-inflammatory properties in immune cells. Gallium can alloy with other metals and be prepared in various composites to modify and tailor its characteristics and functionality. More importantly, the bactericidal mechanism of gallium liquid metal could sidestep the threat of emerging drug resistance mechanisms. Building on this rationale, gallium-based liquid metal nanoparticles can enable impactful and innovative strategic pathways in the battle against antimicrobial resistance. This review outlines the characteristics of gallium-based liquid metals at the nanoscale and their corresponding antimicrobial mechanisms to provide a comprehensive yet succinct overview of their current antimicrobial applications. In addition, challenges and opportunities that require further research efforts have been identified and discussed.

Graphene oxide/gallium nanoderivative as a multifunctional modulator of osteoblastogenesis and osteoclastogenesis for the synergistic therapy of implant-related bone infection.

Currently, implant-associated bacterial infections account for most hospital-acquired infections in patients suffering from bone fractures or defects. Poor osseointegration and aggravated osteolysis remain great challenges for the success of implants in infectious scenarios. Consequently, developing an effective surface modification strategy for implants is urgently needed. Here, a novel nanoplatform (GO/Ga) consisting of graphene oxide (GO) and gallium nanoparticles (GaNPs) was reported, followed by investigations of its in vitro antibacterial activity and potential bacterium inactivation mechanisms, cytocompatibility and regulatory actions on osteoblastogenesis and osteoclastogenesis. In addition, the possible molecular mechanisms underlying the regulatory effects of GO/Ga nanocomposites on osteoblast differentiation and osteoclast formation were clarified. Moreover, an in vivo infectious microenvironment was established in a rat model of implant-related femoral osteomyelitis to determine the therapeutic efficacy and biosafety of GO/Ga nanocomposites. Our results indicate that GO/Ga nanocomposites with excellent antibacterial potency have evident osteogenic potential and inhibitory effects on osteoclast differentiation by modulating the BMP/Smad, MAPK and NF-κB signaling pathways. The in vivo experiments revealed that the administration of GO/Ga nanocomposites significantly inhibited bone infections, reduced osteolysis, promoted osseointegration located in implant-bone interfaces, and resulted in satisfactory biocompatibility. In summary, this synergistic therapeutic system could accelerate the bone healing process in implant-associated infections and can significantly guide the future surface modification of implants used in bacteria-infected environments.

Synthesis of porous γ-gallium oxide films using refrigerator aging oxidation from gallium nanoparticles

Porous gallium oxide films were tried to synthesize at low temperatures. Ga nanoparticle dispersions were synthesized using ultrasound irradiation in 2-propanol and two films methods were considered. In the case of the spray coating of Ga nanoparticle dispersions and treatment with hydrazine vapor, Ga films were obtained. In the case of depositing Ga nanoparticles on a cover glass and aging them in hydrazine solution at a refrigerator temperature, porous γ-Ga2O3 film was synthesized. This new process of low-temperature aging in a refrigerator using hydrazine solution allows synthesizing porous γ-Ga2O3 film. Generally, the synthesis of oxide ceramics requires high-temperature processing, but this method allows oxidation at low temperatures, such as refrigerator temperatures, making it an energy-efficient process.

Gallium Nanoparticles Obtained on Silicon Substrates by Thermal Evaporation Method

Gallium Nanoparticles Obtained on Silicon Substrates by Thermal Evaporation Method

Synthesis of Antimicrobial Gallium Nanoparticles Using the Hot Injection Method

Antibiotic resistance continues to be an ongoing problem in global public health despite interventions to reduce antibiotic overuse. Furthermore, it threatens to undo the achievements and progress of modern medicine. To address these issues, the development of new alternative treatments is needed. Metallic nanoparticles have become an increasingly attractive alternative due to their unique physicochemical properties that allow for different applications and their various mechanisms of action. In this study, gallium nanoparticles (Ga NPs) were tested against several clinical strains of Pseudomonas aeruginosa (DFU53, 364077, and 365707) and multi-drug-resistant Acinetobacter baumannii (MRAB). The results showed that Ga NPs did not inhibit bacterial growth when tested against the bacterial strains using a broth microdilution assay, but they exhibited effects in biofilm production in P. aeruginosa DFU53. Furthermore, as captured by atomic force microscopy imaging, P. aeruginosa DFU53 and MRAB biofilms underwent morphological changes, appearing rough and irregular when they were treated with Ga NPs. Although Ga NPs did not affect planktonic bacterial growth, their effects on both biofilm formation and established biofilm demonstrate their potential role in the race to combat antibiotic resistance, especially in biofilm-related infections.

Plasmonic Properties of Individual Gallium Nanoparticles.

Gallium is a plasmonic material offering ultraviolet to near-infrared tunability, facile and scalable preparation, and good stability of nanoparticles. In this work, we experimentally demonstrate the link between the shape and size of individual gallium nanoparticles and their optical properties. To this end, we utilize scanning transmission electron microscopy combined with electron energy loss spectroscopy. Lens-shaped gallium nanoparticles with a diameter between 10 and 200 nm were grown directly on a silicon nitride membrane using an effusion cell developed in house that was operated under ultra-high-vacuum conditions. We have experimentally proven that they support localized surface plasmon resonances and their dipole mode can be tuned through their size from the ultraviolet to near-infrared spectral region. The measurements are supported by numerical simulations using realistic particle shapes and sizes. Our results pave the way for future applications of gallium nanoparticles such as hyperspectral absorption of sunlight in energy harvesting or plasmon-enhanced luminescence of ultraviolet emitters.

Self-assembled photonic structure: a Ga optical antenna on GaP nanowires.

Semiconductor nanowires are the perfect platform for nanophotonic applications owing to their resonant, waveguiding optical properties and technological capabilities providing control over their crystalline and chemical compositions. The vapor-liquid-solid growth mechanism allows the formation of hybrid metal-dielectric nanostructures promoting sub-wavelength light manipulation. In this work, we explore both experimentally and numerically the plasmonic effects promoted by a gallium (Ga) nanoparticle optical antenna decorating the facet of gallium phosphide (GaP) nanowires. Raman, photoluminescence and near-field mapping techniques are used to study the effects. We demonstrate several phenomena including field enhancement, antenna effect and increase in internal reflection. We show that the observed effects have to be considered when nanowires with a plasmonic particle are used in nanophotonic circuits and discuss the ways for utilization of these effects for efficient coupling of light into nanowire waveguide and field tailoring. The results open up promising pathways for the development of both passive and active nanophotonic elements, light harvesting and sensorics.

Synthesis and evaluation of high thermal conductivity magnetic heat storage inorganic microcapsules simultaneously containing gallium and magnetic nanoparticles by sol-gel method

The authors propose microcapsules encapsulating multiple substances as a multifunctional refrigerant that can transport a large amount of heat due to latent heat while being driven self-excitedly by the application of a magnetic field. In this study, a fully inorganic functional microcapsule was synthesized that simultaneously encapsulates magnetic particles and gallium as a phase-change material and has a silica-coated outer shell. Magnetic particles synthesized by the coprecipitation method were mixed with liquid gallium and dispersed ultrasonically to make the core material. The core material was coated with a silica film using the sol-gel method. SEM and EDS observations confirmed that capsules containing iron and gallium were synthesized. The 1 wt% dispersion of the capsule had a 9.5 % increase in thermal conductivity and, like the metallic nanofluid, had excellent properties as a refrigerant. When latent heat was measured, two peaks of 14.2 and 18.4 °C were detected for the supercooling temperature, indicating that it can be used repeatedly with smaller values than in previous studies. The magnetization hysteresis shows that the material has ferromagnetic properties, responding quickly to a magnetic field and dispersing as the field is released.

Regulation of Sirtuin-3 and ERK1/2/p38MAPK by the combination Ga nanoparticles/γ-radiation low dosage: an effective approach for treatment of hepatocellular carcinoma

BackgroundSynthesized gallium nanoparticles synthesized by grape seed extract were characterized with spherical shape and size range less than100 nm, possessing the functional groups of the biological material. The purpose of this study is to evaluate gallium nanoparticles synthesized by grape seed extract, as an antitumor agent with low dose of γ-radiation against hepatocellular carcinoma in rats. Aim of workThis work aimed to evaluate the antitumor effect of gallium nanoparticles synthesized (GaNPs) by grape seed extract and the co-binded treatment with low dose of γ-radiation on hepatocellular carcinoma in rats, through evaluating their effect on signaling pathways and tumor markers. ResultsCytotoxic activity of GaNPs synthesized by grape seed extract was estimated by mediated cytotoxicity assay on HepG2 cell line that recorded IC50 of 388.8 μg/ml. To achieve these goals, eighty Wistar male rats (120−150 g) will be divided into eight groups, each of 10 rats. The animals are administered with diethylnitrosamine to induce hepatocellular carcinoma and then orally administered with GaNPs synthesized by grape seed extract (38.5 mg/kg) in combination with the exposure of the total body to a low dose of γ-radiation (0.5 Gy). The treatment modulated plasma vascular endothelial growth factor and alpha-fetoprotein. In addition, the immunoblotting results of nuclear factor-kappa beta showed a marked downregulation of extracellular signal-regulated kinase, mitogen-activated protein kinase, and c-Jun NH2-terminal kinase alongside, significantly elevating the level of Sirtuin-3 and caspase-3. ConclusionsIt can be concluded that the combined treatment with GaNPs synthesized by grape seed extract and low dose γ-radiation may have antineoplastic activity against hepatocarcinogenesis by inhibiting signal pathways extracellular signal-regulated kinase/mitogen-activated protein kinase/c-Jun NH2-terminal kinase and stimulating apoptotic protein.

Formation of Gallium Nanoparticles by Thermal Evaporation Method in an Argon Atmosphere

Formation of Gallium Nanoparticles by Thermal Evaporation Method in an Argon Atmosphere

Targeting iron metabolism using gallium nanoparticles to suppress ferroptosis and effectively mitigate acute kidney injury

Targeting iron metabolism using gallium nanoparticles to suppress ferroptosis and effectively mitigate acute kidney injury

Synthesis of Liquid Gallium@Reduced Graphene Oxide Core-Shell Nanoparticles with Enhanced Photoacoustic and Photothermal Performance.

This report presents nanoparticles composed of a liquid gallium core with a reduced graphene oxide (RGO) shell (Ga@RGO) of tunable thickness. The particles are produced by a simple, one-pot nanoprobe sonication method. The high near-infrared absorption of RGO results in a photothermal energy conversion of light to heat of 42.4%. This efficient photothermal conversion, combined with the large intrinsic thermal expansion coefficient of liquid gallium, allows the particles to be used for photoacoustic imaging, that is, conversion of light into vibrations that are useful for imaging. The Ga@RGO results in fivefold and twofold enhancement in photoacoustic signals compared with bare gallium nanoparticles and gold nanorods (a commonly used photoacoustic contrast agent), respectively. A theoretical model further reveals the intrinsic factors that affect the photothermal and photoacoustic performance of Ga@RGO. These core-shell Ga@RGO nanoparticles not only can serve as photoacoustic imaging contrast agents but also pave a new way to rationally design liquid metal-based nanomaterials with specific multi-functionality for biomedical applications.

Plasmon Tuning of Liquid Gallium Nanoparticles through Surface Anodization.

In this work, tunable plasmonic liquid gallium nanoparticles (Ga NPs) were prepared through surface anodizing of the particles. Shape deformation of the Ga NPs accompanied with dimpled surface topographies could be induced during electrochemical anodization, and the formation of the anodic oxide shell helps maintain the resulting change in the particle shape. The nanoscale dimple-like textures led to changes in the localized surface plasmon resonance (LSPR) wavelength. A maximal LSPR red-shift of ~77 nm was preliminarily achieved using an anodization voltage of 0.7 V. The experimental results showed that an increase in the oxide shell thickness yielded a negligible difference in the observed LSPR, and finite-difference time-domain (FDTD) simulations also suggested that the LSPR tunability was primarily determined by the shape of the deformed particles. The extent of particle deformation could be adjusted in a very short period of anodization time (~7 s), which offers an efficient way to tune the LSPR response of Ga NPs.

Wearable Piezoelectric Nanogenerators Based on Core-Shell Ga-PZT@GaOx Nanorod-Enabled P(VDF-TrFE) Composites.

High-output flexible piezoelectric nanogenerators (PENGs) have achieved great progress and are promising applications for harvesting mechanical energy and supplying power to flexible electronics. In this work, unique core-shell structured Ga-PbZrxTi1-xO3 (PZT)@GaOx nanorods were synthesized by a simple mechanical mixing method and then were applied as fillers in a poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) matrix to obtain highly efficient PENGs with excellent energy-harvesting properties. The decoration of gallium nanoparticles on PZT @GaOx nanorods can amplify the local electric field, facilitate the increment of polar β-phase fraction in P(VDF-TrFE), and strengthen the polarizability of PZT and P(VDF-TrFE). The interfacial interactions of GaOx and P(VDF-TrFE) are also in favor of an increased β-phase fraction, which results in a remarkable improvement of PENG performance. The optimized Ga-PZT@GaOx/P(VDF-TrFE) PENG delivers a maximum open-circuit voltage of 98.6 V and a short-circuit current of 0.3 μA with 9.8 μW instantaneous power under a vertical force of 12 N at a frequency of 30 Hz. Such a PENG exhibits a stable output voltage after 6 000 cycles by the durability test. Moreover, the liquid gallium metal offers a mechanical matching interface between rigid PZT and the soft polymer matrix, which benefits the effective, durable mechanical energy-harvesting capability from the physical activities of elbow joint bending and walking. This research renders a deep association between a liquid metal and piezoelectric ceramics in the field of piezoelectric energy conversion, offering a promising approach toward self-powered smart wearable devices.