Nanorods In Order Research Articles

Characterization of Gold-Enhanced Titania: Boosting Cell Proliferation and Combating Bacterial Infestation.

In this study an approach was made to efficaciously synthesize gold enhanced titania nanorods by electrospinning. This study aims to address effects of gold enhanced titania nanorods on muscle precursor cells. Additionally, implant related microbial infections are prime cause of various disastrous diseases. So, there is predictable demand for synthesis of novel materials with multifunctional adaptability. Herein, gold nanoparticles were attached on titania nanorods and described using many sophisticated procedures such as XRD, SEM, EDX and TEM. Antimicrobial studies were probed against Gram-negative Escherichia coli. C2C12 cell lines were exposed to various doses of as-prepared gold enhanced titania nanorods in order to test in vitro cytotoxicity and proliferation. Cell sustainability was assessed through Cell Counting Kit-8 assay at regular intervals. A phase-contrast microscope was used to examine morphology of exposed C2C12 cells and confocal laser scanning microscope was used to quantify cell viability. The findings indicate that titania nanorods enhanced with gold exhibit superior antimicrobial efficacy compared to pure titania. Furthermore, newly synthesized gold-enhanced titania nanorods illustrate that cell viability follows a time and concentration dependent pattern. Consequently, our study provides optimistic findings indicating that titania nanorods adorned with gold hold significant potential as foundational resource for developing forthcoming antimicrobial materials, suitable for applications both in medical and biomedical fields. This work also demonstrates that in addition to being extremely biocompatible, titania nanorods with gold embellishments may be used in a range of tissue engineering applications in very near future.

Preparation of nano-Zn2GeO4/rGO composite photocatalyst and its treatment of synthetic dye wastewater

Zn2GeO4/rGO composite photocatalysts were prepared by hydrothermal method with Zn2GeO4 and GO as precursors, and ethanol/water solvent as a reducing agent. Reduced graphene oxide was combined with Zn2GeO4 nanorods in order to improve photocatalytic activity of Zn2GeO4 through improving its surface area, adsorption capacity, charges separation and transportation ability. Then the composite photocatalysts were characterized by XRD, FESEM, EDS and UV–vis DRS. RhB synthetic dye wastewater was used as the target to investigate the effect of each reaction parameter on the degradation rate; the catalytic performance stability of the composite photocatalyst was investigated under the obtained optimal reaction conditions; and the reaction kinetics and reaction mechanism of the synthetic wastewater treatment process were preliminarily analyzed. The study shows that the Zn2GeO4/rGO composite photocatalyst prepared by hydrothermal method has better photocatalytic activity under xenon light illumination, and the wastewater treatment process conforms first-order reaction kinetic characteristics; during the treatment, the dye molecules are directly degraded by the composite photocatalyst, and no other luminescent groups are produced. The Zn2GeO4/rGO composite photocatalyst with good photocatalytic activity and stability under visible light irradiation can be prepared by hydrothermal method for dye wastewater treatment.

NaYF4 Microstructure, beyond Their Well-Shaped Morphology.

Lanthanide-doped nanoparticles are widely investigated for their optical properties. However, the sensitivity of the lanthanide ions’ luminescence to the local symmetry, useful when investigating structural environments, becomes a drawback for optimized properties in the case of poorly controlled crystallinity. In this paper, we focus on -NaYF4 nanorods in order to provide a detailed description of their chemical composition and microstructure. The combination of detailed XRD analysis and TEM observations show that strong variation may be observed from particles from a same batch of synthesis, but also when considering small variations of synthesis conditions. Moreover, also the nanorods observed by SEM exhibit a very nice faceted shape, they are far from being monocrystalline and present significant local deviation of crystalline symmetry and orientation. All these structural considerations, sensitively probed by polarized emission analysis, are crucial to analyze for the development of optimal systems toward the targeted applications.

Folic Acid-Functionalized Gold Nanorods for Controlled Paclitaxel Delivery: In Vitro Evaluation and Cell Studies.

Short gold nanorods were synthesized (average length 28.08nm, average aspect ratio 3.54), which were functionalized with folic acid (FA) and 8-mercaptooctanoic acid (MOA) or 11-mercaptoundecanoic acid (MDA) and loaded with paclitaxel (PCT). FA was conjugated to the nanorods in order to render them targetable for cancer cells overexpressing folate receptors whereas MOA or MDA was attached on the nanorods in order to generate extra hydrophobic areas for entrapment of hydrophobic drugs such as PCT in the nanorods and in order to provide free carboxylic groups, which would allow for the conjugation of drug or other biofunctional molecules to the nanorods. The functionalized gold nanorods (GNRs-MOA-FA and GNRs-MDA-FA) did not exhibit any significant degree of aggregation in cell culture medium and blood plasma even after a prolonged incubation period of 7days, indicating the adequate colloidal stability of the nanorods in these media. The functionalized nanorods exhibited satisfactory entrapment efficiency (around 40%) for PCT and released less than 25% of their PCT content in phosphate buffer pH 7.4 in 48h. PCT entrapment efficiency was a little higher and PCT release rate a little lower in the GNRs-MOA-FA. Molecular analysis (qPCR) was used to find out that the MDA-MB-231 cancer cell line expresses the folate receptor (FL1R) whereas the MCF-7 cancer cell line does not. The PCT-loaded GNRs-MOA-FA were more cytotoxic than the PCT-loaded GNRs-MOA nanorods against the MDA-MB-231 cells, which probably relates to the higher uptake of the GNRs-MOA-FA nanorods by these cells. The opposite was true in the case of the MCF-7 cells.

Utilization of binary PSO algorithm and DDA method to investigate the plasmonic demultiplexer -based CPA filter

Here, we suggest the possibility of optical circuit design approach by employing the binary optimization of plasmonic nano disks. The proposed mechanism is based on combination of binary particle swarm optimization (BPSO) algorithm and discrete dipole approximation (DDA) method. BPSO, a group of birds including a matrix with binary entries responsible for controlling nano disks in the array, shows the presence with symbol of (‘1’) and the absence with (‘0’). The current research represents a nanoscale and compact 4 channels plasmonic Demultiplexer as optical circuit. It includes 8 coherent perfect absorption (CPA) –type filters. The operation principle is based on the absorbable formation of a conductive path in the dielectric layer of a plasmonic nano-disks waveguide. Since the CPA efficiency depends strongly on the number of plasmonic nano-disks and the nano disks location, an efficient binary optimization method based the BPSO algorithm is used to design an optimized array of the plasmonic nano-rod in order to achieve the maximum absorption coefficient in the ‘off’ state.

Vibronic coupling and band gap trends in CuGeO3 nanorods

We measured the optical response of ${\mathrm{CuGeO}}_{3}$ nanorods in order to reveal size effects on the electronic properties. The vibronically activated $d$-to-$d$ color band excitations are activated by the 131 and 478 ${\mathrm{cm}}^{\ensuremath{-}1}$ phonons, with the relative contribution of the lower frequency O-Cu-O bending mode increasing with decreasing size until it dominates the process. We also uncover trends in the direct band gap, with the charge transfer edge hardening with decreasing size. These findings advance the understanding of size effects in low-dimensional copper oxides.

Binary TLBO algorithm assisted to investigate the supper scattering plasmonic nano rod

A new efficient binary optimization method based Teaching-Learning-Based Optimization (TLBO) algorithm is proposed to design an array of plasmonic nano-rods in order to achieve maximum scattering coefficient spectrum. In binary TLBO (BTLBO), a group of learner consists a matrix with binary entries; control the presence (“1”) or the absence (“0”) of nano-rods in the array. Simulation results show that scattering coefficient strongly depends on the localized position of nano-particles and non-periodic structures have more appropriate response in term of scattering coefficient. This approach can be useful in optical applications such as plasmonic nano-antenna.

Combination of binary particle swarm optimization algorithm and discrete dipole approximation method to investigate the plasmonic circuit-based coherent perfect absorption filter

Here, we suggest the possibility of optical circuit design approach by employing the binary optimization of plasmonic nano rods. The proposed mechanism is based on combination of binary particle swarm optimization (BPSO) algorithm and discrete dipole approximation method. BPSO, a group of birds including a matrix with binary entries responsible for controlling nano rods in the array, shows the presence with symbol of (‘1’) and the absence with (‘0’). The current research represents a nanoscale and compact four channels plasmonic Demultiplexer as optical circuit. It includes eight coherent perfect absorption (CPA)—type filters. The operation principle is based on the absorbable formation of a conductive path in the dielectric layer of a plasmonic nano-rods waveguide. Since the CPA efficiency depends strongly on the number of plasmonic nano-rods and the nano rods location, an efficient binary optimization method based the BPSO algorithm is used to design an optimized array of the plasmonic nano-rod in order to achieve the maximum absorption coefficient in the ‘off’ state.

Synthesis and optical properties of gold nanorods with controllable morphology

Searching for architectural building blocks with tunable morphology and peculiarity is a prominent challenge for novel diagnostic and therapeutic applications. Here, the aqueous-based seed-mediated methods for preparing highly mono-dispersed Au nanorods with a different aspect ratio are systematically studied by controlling the amounts of Ag ions and seeds. We also explore the effect of pH on the synthesis of gold nanorods. The realization of the overlap of longitudinal plasmon band and excitation source with different degrees is made by changing the aspect ratio of nanorod in order to determine its effect on the overall surface enhancement. In addition, the gold octahedra are prepared by overgrowth on Au nanorods. The SERS effects of Au nanorods are researched and the FDTD simulations are performed to reveal the morphology induced plasmon modes.

Investigating the optical XNOR gate using plasmonic nano-rods

In this paper, a coherent perfect absorption (CPA)-type XNOR gate based on plasmonic nano particle is proposed. It consists of two plasmonic nano rod arrays on top of two parallel arms with quartz substrate. The operation principle is based on the absorbable formation of a conductive path in the dielectric layer of a plasmonic nano-particles waveguide. Since the CPA efficiency depends strongly on the number of plasmonic nano-rod and the nano rod location, an efficient binary optimization method based the Particle Swarm Optimization (PSO) algorithm is used to design an optimized array of the plasmonic nano-rod in order to achieve the maximum absorption coefficient in the ‘off’ state and the minimum absorption coefficient in the ‘on’ state. In Binary PSO (BPSO), a group of birds consists a matrix with binary entries, control the presence (‘1′) or the absence (‘0′) of nano rod in the array.

Investigating the optical NOR gate using plasmonic nanorods

SummaryIn this paper, a coherent perfect absorption‐type NOR gate based on plasmonic nano particles is proposed. It consists of two plasmonic nanorod arrays on top of two serial arms with quartz substrate. The operation principle is based on the absorbable formation of a conductive path in the dielectric layer of a plasmonic nanoparticle waveguide. Because the coherent perfect absorption efficiency depends strongly on the number of plasmonic nanorods and the locations of nanorods, an efficient binary optimization method based the Particle Swarm Optimization algorithm is used to design an optimized array of the plasmonic nanorods in order to achieve the maximum absorption coefficient in the ‘off’ state and the minimum absorption coefficient in the ‘on’ state. In Binary Particle Swarm Optimization, a group of birds consists a matrix with binary entries, control the presence (‘1’) or the absence (‘0’) of nanorods in the array. Copyright © 2016 John Wiley & Sons, Ltd.

Optimization of the plasmonic nano-rods-based absorption coefficient using TLBO algorithm

We have used the teaching–learning-based optimization (TLBO) algorithm to design the plasmonic nano-rods in order to achieve the maximum absorption coefficient spectrum. In TLBO, a group of learners controls the nano-rod radius, the nano-rods distance, and the number of nano-rods in two dimensions. This approach is useful in optical applications such as solar cell and plasmonic nano antenna.

Silica-Coated and Bare Akaganeite Nanorods: Structural and Magnetic Properties

We report on structural and magnetic properties of uniform silica-coated akaganeite nanorods with length of L ∼ 80 ± 15 nm and diameter D ∼ 15 ± 5 nm as well as silica shell thickness of about 5 nm. Unexpected negative difference between field-cooled (FC) and zero-field-cooled (ZFC) magnetization ΔM = MFC – MZFC < 0, room temperature ferromagnetism, and exchange bias effect have been found. The nanorods are investigated by X-ray powder diffraction (XRPD), transmission electron microscopy (TEM), and vibrating sample magnetometer (VSM) measurements. The magnetic measurements were also performed on bare akaganeite nanorods in order to discriminate the effects of silica coating on the magnetic properties. The measured coercivity and exchange bias effect of bare β-FeOOH nanorods are much lower compared with same properties of SiO2@β-FeOOH nanorods, emphasizing the effect of silica coating on the magnetic properties. These results are discussed considering the core–shell structure of akaganeite nanorods; i.e., ...

Binary control of plasmonic nano rods to design an optical switch

An efficient binary optimization method named binary particle swarm optimization (BPSO) algorithm was used to optimize an array of plasmonic nano-rods in order to design an optical switch. In the proposed switch, the optical switch has been excited by two monochromatic incident plan-waves with the same frequency and two angles of incident θ = 0 and θ = 90. When only the signal with θ = 0 is applied, the incident wave is transmitted and when both signals are applied to the switch simultaneously, the coherent perfect absorption occurs and the two incident waves are suppressed. Therefore, the signal with θ = 90 acts as control signal. BPSO, a swarm of birds including a matrix with binary entries responsible for controlling nano-rods in the array, shows the presence with symbol of (‘1’) and the absence with (‘0’).

Enhanced light trapping and plasmonic properties of aluminum nanorods fabricated by glancing angle deposition

Vertically aligned arrays of aluminum (Al) nanorods were fabricated by glancing angle deposition (GLAD) method. Nanorods with maximum lengths of 200 and 350 nm were grown on 100 nm flat Al thin film. Total and diffuse reflectance profiles were measured using an ultraviolet–visible–near infrared (UV-Vis-NIR) spectrophotometer utilizing an integrating sphere to study detailed optical properties of Al nanorods in comparison to conventional planar Al thin film samples. Finite-difference-time-domain (FDTD) optical modeling method was utilized to simulate the optical response of Al nanorod array and thin film structures. FDTD simulations were carried out for periodic and random arrays of Al nanorods as well as for an isolated single nanorod in order to investigate effects of geometrical structure on plasmonic and light trapping effects. UV-Vis-NIR spectrum results reveal that total reflectance is inversely proportional with nanorod length, and decreases down to as low as ∼25%–30% in the visible spectrum at wavelengths smaller than ∼750 nm, while it stays at ∼85%–90% for flat Al thin films at those wavelengths. FDTD simulation results indicate significant light absorption by GLAD Al nanorods mainly originating from enhanced light trapping and surface plasmon resonance among the nanorods.

Binary optimization of gold nano-rods for designing an optical modulator

An optical modulator with ultra small plasmonic nano rods that can filter the coherent optical frequency is developed. The performance of optical modulator based on dimmer metal nano rods on the top of silicon waveguides as coherent perfect absorber (CPA) is studied. In the proposed model, the optical modulator is excited by two monochromatic incident plan waves with the same frequencies and two polar angles "$$\uptheta =0$$?=0" and "$$\uptheta =\Pi /2$$?=?/2". When the signal with $$\uptheta =0$$?=0 is applied to the modulator separately, the incident wave transmits from the first path and suppresses for the second one, while when both signals are applied to the modulator simultaneously, the CPA occurs for the first path and the ligthwave transmits from the second one. Therefore for two paths there are two states. "on" state when ligthwave transmitted from each path and "off" state when ligthwave suppressed. In this case two paths consist of different array of nano rods locations. Since the CPA efficiency depends strongly on the number of plasmonic nano rods and the nano rods location, a new efficient binary optimization method based the teaching---learning-based optimization (TLBO) algorithm is proposed to design an optimized array of the plasmonic nano-rods in order to achieve the maximum absorption coefficient in the `off' state and the minimum absorption coefficient in the `on' state. In Binary TLBO, a group of learner consists a matrix with binary entries, control the presence (`1') or the absence (`0') of nano rods in the array.

Thermal diffusivity study of nanoparticles and nanorods of titanium dioxide (TiO2) and titanium dioxide coated with cadmium sulfide (TiO2CdS)

Thermal lens (TL) technique was used to obtain the thermal diffusivity of nanoparticles (nPs) and nanorods (nRs) of TiO2 and TiO2CdS, respectively. The nanoparticles with spherical shape have 25nm diameter and rod-shapes have different nanometric diameters by length measurements, both contained in ethanol. The nPs and nRs have been successfully prepared by sol–gel and electrospinning techniques. TL provides reliable alternative to measure the thermal diffusivities of semitransparent materials and low thermal diffusivities. The results show that for nanoparticles with different concentrations, for a higher concentration there is an increase in the thermal diffusivity. On the other hand, comparing different nanostructure forms (nanoparticles and nanorods) for the same concentration, a higher value of thermal diffusivity is observed for nanorods. Complementary techniques such as transmission electron microscopy (TEM), scanning electron microscopy (SEM) and UV–vis spectroscopy were employed to characterize the nanoparticles and nanorods in order to study their morphology, average particle size and absorption spectra. This investigation has future applications for solar cells and electrochemical cells.

High-speed optical FSK demodulator using plasmonic nanorods

An optical frequency-shift keying (FSK) demodulator with ultrasmall plasmonic nanorods that can filter the coherent optical frequency is developed. Since the filtering efficiency depends strongly on the position and number of the plasmonic nanorods in the array, binary teaching–learning-based optimization (BTLBO) algorithm is proposed to design an array of the plasmonic nanorods in order to achieve maximum absorption coefficient spectrum. In BTLBO, a group of learner consists of a matrix with binary entries; control the presence (‘1’) or the absence (‘0’) of the nanoparticles in the array.

Investigating the Optical Switch Using Dimer Plasmonic Nano-Rods

The optical switch based on the dimer plasmonic nano-rods on the silicon waveguide has been numerically analyzed. In the proposed switch, the optical switch has been excited by two monochromatic incident plan-waves with the same frequency and two angles of incident θ = 0 and θ = 90. When only the signal with θ = 0 is applied, the incident wave is transmitted and when both signals are applied to the switch simultaneously, the coherent perfect absorption (CPA) occurs and the two incident waves are suppressed. Therefore, the signal with θ = 90 acts as control signal. Since the CPA efficiency depends strongly on the number of plasmonic nano-rods and the nano-rods location, a new efficient binary optimization method based on the teaching-learning-based optimization (TLBO) algorithm is proposed to design an optimized array of the plasmonic nano-rods in order to achieve the maximum absorption coefficient in the “off” state and the minimum absorption coefficient in the “on” state. In binary TLBO, a group of learner includes a matrix with binary entries, and is used to control the presence (“1”) or the absence (“0”) of nano-rods in the array.

Molecular self-assembly of nylon-12 nanorods cylindrically confined to nanoporous alumina.

Molecular self-assembly of nylon-12 rods in self-organized nanoporous alumina cylinders with two different diameters (65 and 300 nm) is studied with transmission electron microscopy (TEM) and wide-angle X-ray diffraction (WAXD) in symmetrical reflection mode. In a rod with a 300 nm diameter, the tendency of the hydrogen-bonding direction of a γ-form crystal parallel to the long axis of the rod is not clear because of weak two-dimensional confinement. In a rod with a diameter of 65 nm, the tendency of the hydrogen-bonding direction of a γ-form crystal parallel to the long axis of the rod is more distinct because of strong two-dimensional confinement. For the first time, selected-area electron diffraction (SAED) is applied in a transmission electron microscope to a polymer nanorod in order to determine the hydrogen-bond sheet and lamellar orientations. Results of TEM-SAED and WAXD showed that the crystals within the rod possess the γ-form of nylon-12 and that the b axis (stem axis) of the γ-form crystals is perpendicular to the long axis of the rod. These results revealed that only lamellae with 〈h0l〉 directions are able to grow inside the nanopores and the growth of lamellae with 〈hkl〉 (k ≠ 0) directions is stopped owing to impingements against the cylinder walls. The dominant crystal growth direction of the 65 nm rod in stronger two-dimensional confinement is in between the [-201] and [001] directions due to the development of a hydrogen-bonded sheet restricted along the long axis of the rod.