Shape Of Nanoparticles Research Articles

Fabrication of nanoparticles with precisely controllable plasmonic properties as tools for biomedical applications.

Metal nanoparticles are established tools for biomedical applications due to their unique optical properties, primarily attributed to localized surface plasmon resonances. They show distinct optical characteristics, such as high extinction cross-sections and resonances at specific wavelengths, which are tunable across the wavelength spectrum by modifying the nanoparticle geometry. These attributes make metal nanoparticles highly valuable for sensing and imaging in biology and medicine. However, their widespread adoption is hindered due to challenges in consistent and accurate nanoparticle fabrication and functionality as well as due to nanotoxicological concerns, including cell damage, DNA damage, and unregulated cell signaling. In this study, we present a fabrication approach using nanoimprint lithography in combination with thin film deposition which yields highly homogenous nanoparticles in size, shape and optical properties with standard deviations of the main geometry parameters of less than 5% batch-to-batch variation. The measured optical properties closely match performed simulations, indicating that pre-experimental modelling can effectively guide the design of nanoparticles with tailored optical properties. Our approach also enables nanoparticle transfer to solution. Particularly, we show that the surface coating with a PEG polymer shell ensures stable dispersions in buffer solutions and complex cell media for at least 7 days. Furthermore, our in vitro experiments demonstrate that these nanoparticles are internalized by cells via endocytosis, exhibit good biocompatibility, and show minor cytotoxicity, as evidenced by high cell viability. In the future, our high-precision nanoparticle fabrication method together with tunable surface plasmon resonance and reduced nanotoxicity will offer the possibility to replace conventional nanomaterials for biomedical applications that make use of an optical response at precise wavelengths. This includes the use of the nanoparticles as contrast agents for imaging, as probes for targeted photothermal cancer therapy, as carriers for controlled drug delivery, or as probes for sensing applications based on optical detection principles.

Organelle-Targeting Nanoparticles.

Organelles are specialized subunits within cells which carry out vital functions crucial to cellular survival and form a tightly regulated network. Dysfunctions in any of these organelles are linked to numerous diseases impacting virtually every organ system in the human body. Targeted delivery of therapeutics to specific organelles within the cell holds great promise for overcoming challenging diseases and improving treatment outcomes through the minimization of therapeutic dosage and off-target effects. Nanoparticles are versatile and effective tools for therapeutic delivery to specific organelles. Nanoparticles offer several advantageous characteristics, including a high surface area-to-volume ratio for efficient therapeutic loading and the ability to attach targeting moieties (tethers) that enhance delivery. The choice of nanoparticle shape, size, composition, surface properties, and targeting ligands depends on the desired target organelle and therapeutic effect. Various nanoparticle platforms have been explored for organelle targeting, such as liposomes, polymeric nanoparticles, dendrimers, and inorganic nanoparticles. In this review, current and emerging approaches to nanoparticle design are examined in the context of various diseases linked to organelle dysfunction. Specifically, advances in nanoparticle therapies targeting organelles such as the nucleus, mitochondria, lysosomes/endosomes, Golgi apparatus, and endoplasmic reticulum are comprehensively and critically discussed.

Bacterial Kinetics for Control Shape and Biogenic Synthesis of Nanoparticles: Review

Bacterial Kinetics for Control Shape and Biogenic Synthesis of Nanoparticles: Review

Growth‐Based Analyte and Bioanalyte Sensing Applications Using Noble Metal Nanoparticles: Effect of Nanoparticle Growth on the Localized Surface Plasmon Resonance Signal

Noble metal (gold and silver) nanoparticles have found a range of applications as sensors and biosensors. These applications utilize the nanoparticles’ tunable optical properties within the visible range of the electromagnetic spectrum, which originate from localized surface plasmon resonance. Recent applications have focused on analyte and bioanalyte detection through nanoparticle growth while successfully achieving low detection limits. This review focuses on theoretical and empirical models used to quantify and/or optimize the localized surface plasmon resonance response to nanoparticle growth, with representative examples from the literature. The effect of nanoparticle growth on the localized surface plasmon resonance signal in monometallic nanoparticles, bimetallic core‐shell nanoparticles, and monometallic nanoshells will be discussed, including spherical, spheroidal and non‐spheroidal nanoparticle shapes. 1. Introduction 1. Introduction

Nanoparticle shape is the game-changer for blood-brain barrier crossing and delivery through tunneling nanotubes among glioblastoma cells.

Tunneling nanotubes (TNTs) are thin, dynamic, long membrane protrusions that allow intercellular exchanges of signaling clues, molecules and organelles. The presence of TNTs and their involvement as drug delivery channels have been observed in several types of cancer, including glioblastoma. Recently, increased attention has been directed toward nanoparticles (NPs) that can be transported in TNTs. However, few data are available on the role of physical parameters of nanoparticles, such as size, shape, charge and flexibility, in determining their transfer efficiency between cells by TNTs. Here, we focused our attention on NP shape, manufacturing spherical, discoidal and deformable negatively charged lipid-based NPs with sizes <120 nm and similar stiffness. The TNT-mediated transfer of NPs was investigated in 2D and 3D culture models of human glioblastoma cells. The permeability and biocompatibility of the blood-brain barrier (BBB) were also assessed. Results showed that discoidal NPs displayed the highest TNT-mediated transfer efficiency between cancer cells, with a maximum velocity of 69 nm s-1, and a higher endothelial permeability (1.29 × 10-5 cm min-1) across the BBB in an in vitro model. This depends on the NP shape because discoidal NPs have a larger surface area exposed to the flow along the TNT channel. Overall, the results suggest that the shape of NPs is the game-changer for more efficient TNT-mediated transfer between cancer cells, thus introducing a sustainable solution to improve the diffusion rate at which the NPs spread in the tumour microenvironment, opening the possibility of ameliorating drug distribution to difficult-to-reach cancer cell populations.

A review of innovative design strategies: Artificial antigen presenting cells in cancer immunotherapy.

Developing nanocarriers that can carry medications directly to tumors is an exciting development in cancer nanomedicine. The efficacy of this intriguing therapeutic approach is, however, compromised by intricate and immunosuppressive circumstances that arise concurrently with the onset of cancer. The artificial antigen presenting cell (aAPC), a micro or nanoparticle based device that mimics an antigen presenting cell by providing crucial signal proteins to T lymphocytes to activate them against cancer, is one cutting-edge method for cancer immunotherapy. This review delves into the critical design considerations for aAPCs, particularly focusing on particle size, shape, and the non-uniform distribution of T cell activating proteins on their surfaces. Adequate surface contact between T cells and aAPCs is essential for activation, prompting engineers to develop nano-aAPCs with microscale contact areas through techniques such as shape modification and nanoparticle clustering. Additionally, we explore recommendations for future advancements in this field.

Influence of nanoparticle shape on hydrogen absorption in Palladium: A combined DFT and atomistic approach

Influence of nanoparticle shape on hydrogen absorption in Palladium: A combined DFT and atomistic approach

Plasma-induced nanogap narrowing and morphological transformation in gold nanoparticle assemblies.

The plasmonic properties of gold nanoparticle (AuNP) assemblies are critically influenced by the nanogaps between particles. Here, we demonstrate that plasma treatment effectively narrows these nanogaps and ultimately merges the nanoparticles. This process induces a sequential redshift, weakening, broadening, and an eventual blueshift of the plasmon coupling peak in UV-vis spectra, indicating transitions from classical to quantum regimes and finally to contact modes. Surface-enhanced Raman spectroscopy reveals an initial increase in intensity as the nanogaps narrow, followed by a decline as linker molecules are removed. Transmission electron microscopy images further show significant deformation of AuNPs after 5 min of plasma treatment. Based on these combined observations, we propose that the oxidative desorption of thiol linkers causes the collapse of self-assembled monolayers, leading to the gradual narrowing of nanogaps and eventual particle fusion. This plasma-induced transformation also enables the creation of novel AuNP shapes, such as nano-snowmen and particles with protruding morphologies, by merging heterodimers or core-satellite structures. Our findings not only deepen the understanding of plasma effects on nanoparticle assemblies but also expand the utility of plasma treatment for controlling nanogap distances and fabricating exotic nanoparticle shapes.

Exploring the Gyrotactic Microorganisms flow over cylinder/plate with Eyring-Powell model and hybrid nanofluids of Varied Nanoparticle Shapes

Exploring the Gyrotactic Microorganisms flow over cylinder/plate with Eyring-Powell model and hybrid nanofluids of Varied Nanoparticle Shapes

Green synthesis of silver nanoparticles from endophytic fungus Colletotrichum sp. with special emphasis on antibacterial, antioxidant and plant growth promoting potential

The creation of "microbial nanotechnology" for quick and large-scale manufacturing of nanoparticles would be possible with an effective biosynthesis method. Plumbago zeylanica L. is a medicinal plant from which the endophytic fungus Colletotrichum sp. was isolated and identified by 18S rDNA sequencing and microscopic studies. Cell filtrate of Colletotrichum sp. was employed to produce biological silver nanoparticles which acted as a reducing and stabilising agent during this process. The brown colour proved that silver nanoparticles (AgNPs) are being produced. In characterization of AgNPs, ultraviolet-visible spectroscopy revealed maximum absorption at 425 nm. From transmission electron microscopy and field emission scanning electron microscopic study the shape of the silver nanoparticle was found spherical with 10–30 nm diameters. The existence of elemental silver (peak) was verified by the silver signal in the energy-dispersive X?ray spectroscopy. Fourier-transform infrared analysis showed some major and minor shifts in the peaks of some chemical bonding. Synthesised AgNP had strong antibacterial action against pathogenic bacterial strains in 200 g/mL concentration and against Pseudomonas aeruginosa MTCC 741, it showed the highest inhibition. The AgNP concentration of 150 g/mL demonstrated the highest competency for antioxidant capabilities while ascorbic acid was used as the reference. Also, AgNP exhibited plant growth-promoting ability as in 40 mg/L concentration; it significantly enhanced the shoot and root growth, total soluble protein, sugar, and indole acetic acid content of P. zeylanica L. This AgNP can be useful in pharmaceutical industries and agriculture as nano fertilizers for all these purposes.

Green Synthesis of Silver Nanoparticles Using Gempur Batu Leaf Extract (Ruellia napifera) as Antibacterial, Antibiofilm, and Antioxidant

Silver Nanoparticles basically focus on the synthesis of nano-sized particles produced through chemical, physical, and biological processes, which contribute significantly to the control of plant and animal diseases and have shown considerable promise in improving the quality of human living conditions and health. The method of making silver nanoparticles, namely Green synthesis, involves the use of plants for the synthesis process of various types of nanoparticles. Green synthesis has the advantages of a simple method, environmentally friendly, non-polluting, antitoxic, and cost-effective. The purpose of this study was to determine the antibacterial and antioxidant activities of AgNPs. In the spectrophotometer absorption spectrum appears at a wavelength of 450 nm. FTIR measurements were used to determine the presence of bioactive molecules that may be responsible for the stabilization that acts as a capping agent. The absorption spikes at 3256, 1552, 1048, and 934 cm−1 were determined for gempur batu leaf extract, while silver nanoparticles showed absorption spikes at 3369, 1576, 1080, and 822 cm−1. The results of XRD analysis of AgNPs showed that they had been successfully synthesized, which can be seen from the formation of narrow peaks indicating the crystalline nature of the formed nanoparticles. The results of TEM analysis of AgNPs in this study are a mixture of spherical, hexagonal, and triangular shapes of silver nanoparticles. The antibacterial activity test of silver nanoparticles with gempur batu leaf extract with variations in AgNO3 solution concentration has been successful, which is indicated by the formation of inhibition zones for Eschericia coli and Staphylococcus aureus bacteria. The results of antioxidant activity in AgNPss show an increasing percentage of inhibition along with increasing concentration of AgNPss increasing from 1 to 15 ppm and ascorbic acid increasing from 1 to 5 ppm. Antibiofilm activity in AgNPs has a good ability to inhibit the formation of biofilm layers in Staphylococcus aureus and Escherichia coli bacteria by having a biofilm inhibition percentage of more than 50%.

In Vitro and In-Silico Assessment of Gaussian Curvature-driven Internalization Kinetics of Nanoparticles.

Nanoparticles have been of significant interest in various biomedical domains such as drug delivery, gene delivery, cytotoxicity analysis, and imaging. Despite the synthesis of a variety of nanoparticles, their cellular uptake efficiency remains a substantial obstacle, with only a small fraction of delivered nanoparticles (NPs) have been reported to traverse the cell membrane within 24 h. Consequently, higher doses are often necessitated, leading to increased toxicity concerns. In this investigation, we illustrate that nanoparticles having negative Gaussian curvature demonstrate rapid and efficient internalization into cells by lowering the energy barrier for membrane bending. Specifically, three types of gold nanoparticles; gold nanorods (GNR), gold nanodogbones at pH 4 (GDB4), and gold nanodogbones at pH 6 (GDB6) were synthesized, with Gaussian curvatures of 0, -166.91, and -376.62, respectively. Cellular uptake studies conducted via ICP-OES analysis reveal that GDB6 is taken up 140% more in A549 cells and 77% more in NIH3T3 cells compared to GNR. Confocal microscopy-based uptake studies further confirm the higher uptake of GDB6 compared to GNR. Additionally, molecular simulations indicate that GDB nanoparticles exhibit a significantly larger free energy change during translocation compared to GNR, emphasizing the impact of nanoparticle shape on uptake and translocation through the membrane and validating the efficacy of negative Gaussian curvature in enhancing cellular uptake, consistent with experimental observations. Overall, our findings emphasize the importance of nanoparticle curvature modulation in maximizing cellular uptake efficiency for improved biomedical applications, providing valuable insights into the design of nanomaterials for drug delivery purposes.

Silver Nanoparticle Morphology Control via Fruit Juice: A Comprehensive Review

This review examines the impact of fruit juice on the morphology of silver nanoparticles. Fruit juice contains reducing agents that can be useful in synthesizing nanoparticles, potentially affecting their shape. The review also discusses the method of synthesizing silver nanoparticles using fruit juice as the reducing agent and the various characterization techniques used to determine their morphology. The results indicate that fruit juice plays a crucial role in controlling the shape of silver nanoparticles. Factors such as the type of fruit, concentration, mixing time, pH, ratio of silver nitrate, and temperature can influence the final size and shape of the nanoparticles. These findings suggest that using fruit juice as a reducing agent in nanoparticle synthesis can be a promising approach for manipulating their morphology. This review introduces new possibilities for the application of nanoparticles in healthcare, electronics, and catalysis.

Up-Conversion Photoluminescence Reconfiguration in Silicon by Inner Microstructure Control of Hybrid Plasmonic-Semiconductor Nanoparticles.

Hybrid metal-semiconductor nanostructures unifying plasmonic and high-refractive-index materials in a single resonant system demonstrate a wide set of unique optical properties. Such systems are a perspective for a broad palette of applications, but the link between their inner structure and optical properties is a very sensitive issue, which is still not revealed. Here, we describe the influence of internal microstructure of a hybrid gold-silicon nanoparticle (the gold nanoparticle with embedded silicon nanograins) on the up-conversion white-light photoluminescence. The evolution in the internal microstructure of the system during thermal treatment up to 500 °C is tracked in situ through the HAADF and EDS STEM techniques. The studies show the redistribution of the materials inside the hybrid nanoparticle and the reduction of the silicon nanograin numbers under heating without an external modification of the nanoparticle shape. We have established numerically that the dependence of the enhancement factor spectral width on the S/V ratio of the nanoparticle plasmonic component is close to the linear behavior. The shrinkage of the photoluminescence spectrum (up to 42%) of the hybrid nanoparticle reconfigured by laser exposure and thermal treatment is shown experimentally, which supports our numerical conclusions. The results shed light on the connection of optical properties of complex hybrid systems with their complex internal composition, providing a powerful tool to control their optical properties through microstructure rearrangement. They also open the way to the development of reconfigurable silicon-based up-conversion light nanosources for integrated optical devices and biophotonics.

Automated Gold Nanorod Spectral Morphology Analysis Pipeline.

The development of a colloidal synthesis procedure to produce nanomaterials with high shape and size purity is often a time-consuming, iterative process. This is often due to quantitative uncertainties in the required reaction conditions and the time, resources, and expertise intensive characterization methods required for quantitative determination of nanomaterial size and shape. Absorption spectroscopy is often the easiest method for colloidal nanomaterial characterization. However, due to the lack of a reliable method to extract nanoparticle shapes from absorption spectroscopy, it is generally treated as a more qualitative measure for metal nanoparticles. This work demonstrates a gold nanorod (AuNR) spectral morphology analysis tool, called AuNR-SMA, which is a fast and accurate method to extract quantitative structural information from colloidal AuNR absorption spectra. To demonstrate the practical utility of this model, we apply it to three distinct applications. First, we demonstrate this model's utility as an automated analysis tool in a high-throughput AuNR synthesis procedure by generating quantitative size information from optical spectra. Second, we use the predictions generated by this model to train a machine learning model to predict the resulting AuNR size distributions under specified reaction conditions. Third, we apply this model to spectra extracted from the literature where no size distributions are reported and impute unreported quantitative information on AuNR synthesis. This approach can potentially be extended to any other nanocrystal system where absorption spectra are size dependent, and accurate numerical simulation of absorption spectra is possible. In addition, this pipeline could be integrated into automated synthesis apparatuses to provide interpretable data from simple measurements, help explore the synthesis science of nanoparticles in a rational manner, or facilitate closed-loop workflows.

Analyzing thermal performance and entropy generation in time-dependent buoyancy flow of water-based over rotating sphere with ternary nanoparticle shape factor

Abstract The heat transfer augmentation, solar power systems, medical equipment, semiconductor cooling, aerospace, and automotive industries all use ternary hybrid nanofluids (Thnf). The current study is mainly about a magnetized Thnf flow that can't be squished around a spinning sphere that has different viscosity, thermal conductivity, and shape (brick, platelets, cylinder, blade). The heat transport simulation incorporates the principles of viscous dissipation and joule heating. Water is mixed with silver, magnesium oxide, and iron trioxide to make the ternary hybrid nanofluid. Similarity substitution converts model equations to ordinary differential equations (ODEs). Runge-Kutta fourth order numerically estimates the non-dimensional set of ODEs. For certain emergent parameters, velocity, temperature, entropy generation, Nusselt number, and skin friction are computed and analyzed. The research shows that entropy generation increases with brinkman number, nanoparticle volume fraction and magnetic parameters and reduces with temperature difference parameter. Increasing the unsteadiness parameter upsurges velocity in the x-direction, but decreases it in the z-direction and temperature curve. Skin friction upsurges in the x-direction and declines in the z-direction with rotation. Platelet-shaped nanoparticles usually outperform blade, brick, and cylinder shapes. When mass suction $( S )$ is elevated from 1.0 to 2.0, the heat transfer rate increases by 47.25% for the Brick form, 47.26% for the Platelets shape, 35.08% for the Cylinders shape, and 37.65% for the Blades shape. Comparing the results to prior literature shows excellent agreement.

Thermo-Responsive and Electroconductive Nano Au-PNiPAAm Hydrogel Nanocomposites: Influence of Synthesis Method and Nanoparticle Shape on Physicochemical Properties.

Hydrogel nanocomposites that respond to external stimuli and possess switchable electrical properties are considered as emerging materials with potential uses in electrical, electrochemical, and biological devices. This work reports the synthesis and characterization of thermo-responsive and electroconductive hydrogel nanocomposites based on poly(N-isopropylacrylamide) (PNiPAAm) and gold nanoparticles (nanospheres-AuNPs and nanorods-AuNRs) using two different synthetic techniques. Method I involved γ-irradiation-induced crosslinking of a polymer matrix (hydrogel), followed by radiolytic in situ formation of gold nanoparticles, while Method II included the chemical synthesis of nanoparticles, followed by radiolytic formation of a polymer matrix around the gold nanoparticles. UV-Vis spectral studies revealed the presence of local surface plasmon resonance (LSPR) bands characteristic of nanoparticles of different shapes, confirming their formation and stability inside the polymer matrix. Morphological, structural, and physicochemical analyses indicated the existence of a stable porous polymer matrix, the formation of nanoparticles with a face-centered cubic structure, increased swelling capacity, and a slightly higher volume phase transition temperature (VPTT) for the hydrogel nanocomposites. Comparative electrochemical impedance spectroscopy (EIS) showed an increase in conductivity for the nano Au-PNiPAAm hydrogel nanocomposites compared to the PNiPAAm hydrogel, with a considerable rise detected above the VPTT. By reverting to room temperature, the conductivity decreased, indicating that the investigated hydrogel nanocomposites exhibited a remarkable reversible "on-off" thermo-switchable mechanism. The highest conductivity was observed for the sample with rod-shaped gold nanoparticles. The research findings, which include optical, structural, morphological, and physicochemical characterization, evaluation of the efficiency of the chosen synthesis methods, and conductivity testing, provide a starting point for future research on the given nanocomposite materials with integrated multifunctionality.

Catalytic degradation of aromatic dyes using triazolidine-thione stabilized Nickel nanoparticles

Nanoparticles have been extensively studied for many years due to their important roles in catalysis, metallurgy and high temperature superconductors. But, Nanoparticles are extremely unstable and easily react with other substances. So, to control the size and the shape of nanoparticles they must be stabilized. Organic Ligands have gain more attention for stabilizing Nanoparticles. In the present work, Nickel Nanoparticles have been synthesized by reduction method and then stabilized by synthesized 5-phenyl triazolidine-thione based organic ligand to achieve larger surface area and good catalytic activity. Stabilized Nickel NPs of different ratios were synthesized for analyzing their catalytic performance against dyes that has become one of the most serious environmental problem causing drastic water pollution. The prepared thione stabilized Nickel nanoparticles were confirmed by UV-Visible and Infrared Spectroscopy. UV/Vis analysis displayed the peak at 236 nm which confirms the metallic Ni NPs formation while, in FTIR peak around 720-750cm-1 is due to the nickel and sulphur bond stretching vibrations. The size, surface morphology and the quality of the stabilized Ni Nanoparticles were analyzed by Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD) analysis. SEM images showed uneven morphology with variously sized and shaped particles. Large surface area is visible which is advantageous for catalytic degradation of pollutants. The degradation process was studied by using UV-visible Spectroscopy. The catalytic behavior of stabilized nanoparticles was evaluated by using various parameters i.e. time, concentration and size of NPs. These parameters were optimized during degradation process to get maximum degradation in short period of time. Maximum percentage degradation of Methylene blue, Methyl Orange and Rhodamine B dyes were achieved up to 90%, 88% and 81% respectively, in short duration of time. All the three ratios of thione stabilized Ni Nanoparticles showed good degrading performance for all dyes, but 1:2 thione stabilized Ni NPs had shown maximum catalytic performance.

Effect of nanoparticles shape on the magneto-mechanical actuation of biomolecules in magnetic fields of various configurations

Effect of nanoparticles shape on the magneto-mechanical actuation of biomolecules in magnetic fields of various configurations

Impact of nanoparticles shapes and fuzzy volume fraction on Al2O3 - H2O nanofluid flow past an unsteady expandable surface

Impact of nanoparticles shapes and fuzzy volume fraction on Al2O3 - H2O nanofluid flow past an unsteady expandable surface