Lasing in an assembled array of silver nanocubes.

We demonstrate a surface lattice resonance (SLR)-based plasmonic nanolaser that leverages bulk production of colloidal nanoparticles and assembly on templates with single particle resolution. SLRs emerge from the hybridization of the plasmonic and photonic modes when nanoparticles are arranged into periodic arrays and this can provide feedback for stimulated emission. It has been shown that perfect arrays are not a strict prerequisite for producing lasing.

Magnetic-assisted sequential templated self-assembly of hybrid colloid nanoparticle systems.

The assembly of hybrid nanoparticles is a pioneering route for developing nanoscale functional devices, enabling breakthroughs in various fields, including electronics, photonics, energy, sensing, and biomedical applications. Here, we focus on the templated assembly of nano-sized colloidal systems using a combination of silica-coated superparamagnetic beads (MBs) and polymer-coated gold nanoparticles (AuNPs) or silver nanoparticles (AgNPs). These hybrid nanoparticles introduce new functionalities that allow them to be used as nanomachines with numerous possible applications.

Lateral flow assay sensitivity and signal enhancement via laser µ-machined constrains in nitrocellulose membrane.

Lateral flow assay (LFA) is a handful diagnostic technology that can identify severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and other common respiratory viruses in one strip, which can be tested at the point-of-care without the need for equipment or skilled personnel outside the laboratory. Although its simplicity and practicality make it an appealing solution, it remains a grand challenge to substantially enhance the colorimetric LFA sensitivity. In this work, we present a straightforward approach to enhance the sensitivity of LFA by imposing the flow constraints in nitrocellulose (NC) membranes via a number of vertical femtosecond laser micromachined microchannels which is important for prolonged specific binding interactions.

Effects of carbazolyl and diphenylamino substituents bearing methoxy groups on the performance of hole-transporting materials in OLEDs.

Newly designed and synthesized derivatives of pentaphenylbenzene with methoxy-substituted carbazolyl or diphenylamino moieties were investigated to estimate their applicability as hole transport materials. Both the compounds exhibit high thermal stability. The intramolecular charge transfer is blocked for the film of the compound containing diphenylamino groups.

In situ optical sub-wavelength thickness control of porous anodic aluminum oxide.

Porous anodic aluminum oxide (PAAO), sometimes referred to as nanoporous anodic alumina, serves as a cost-effective template for nanofabrication in many fields of science and engineering. However, production of ultrathin PAAO membranes with precise thickness in the optical sub-wavelength range remains challenging because of difficulties regarding process control at the initial stage of anodic oxidation. In this study, we demonstrate a technique for consistently manufacturing PAAO with the targeted thickness.

Shape influence on the ultrafast plasmonic properties of gold nanoparticles.

The aim of shape-controlled colloidal synthesis of gold (Au) is to produce Au nanoparticles (NPs) with fine control of shapes, sizes, and dispersities. We show how transient absorption spectroscopy (TAS) can be used to rapidly and accurately quantify the vast ensemble of shapes of Au NPs in solution within minutes, including the synthesized nanorods, decahedra, and nanospheres. Colloidal solutions containing Au NPs were measured in TAS and their localized surface plasmon resonance (LSPR) modes were classified according to the shape, wavelength and number of peaks.

Nanotechnologies in Textiles.

Textiles, originally made from natural fiber materials, have thousands of years of history [...

One Step In-Situ Synthesis of Zinc Oxide Nanoparticles for Multifunctional Cotton Fabrics.

Zinc oxide nanoparticles (ZnO NPs) have acquired great significance in the textile sector due to their impressive efficiency and multifold utilization, such as antimicrobials, UV protection, photo catalytic activity, and self-cleaning. The aim of this work is in-situ growth of ZnO NPs on 100% cotton fabrics with the one-step hydrothermal method for preparation of multifunctional textile with UV protecting, antibacterial, and photo catalytic properties. Sodium hydroxide (NaOH) and Zinc nitrate hexahydrate [Zn(NO)·6HO] were used as reactants for the growth of zinc oxide on the 100% cotton fabrics.

Preclinical Study of a Multi-Layered Antimicrobial Patch Based on Thin Nanocomposite Amorphous Diamond Like Carbon Films with Embedded Silver Nanoparticles.

A growing number of severe infections are related to antibiotic-resistant bacteria, therefore, in recent years, alternative antimicrobial materials based on silver nanoparticles (NPs) attracted a lot of attention. In the current research, we present a medical patch prototype containing diamond-like carbon nanocomposite thin films doped with silver nanoparticles (DLC:Ag), as a source of silver ions, and an aqueous mass of the gelatin/agar mixture as a silver ion accumulation layer. The DLC:Ag thin films with 3.

Surface Lattice Resonances in Self-Assembled Arrays of Monodisperse Ag Cuboctahedra.

Plasmonic metal nanoparticles arranged in periodic arrays can generate surface lattice plasmon resonances (SLRs) with high -factors. These collective resonances are interesting because the associated electromagnetic field is delocalized throughout the plane of the array, enabling applications such as biosensing and nanolasing. In most cases such periodic nanostructures are created top-down nanofabrication processes.

Dot-Matrix Hologram Rendering Algorithm and its Validation through Direct Laser Interference Patterning.

The fight against forgery of valuable items demands efficient and reasonably priced solutions. A security tag featuring holographic elements for anti-counterfeiting is one of them. However, the content and colours of a diffraction image that would be seen by an observer are often counterintuitive in the design stage.

Giant Negative Piezoresistive Effect in Diamond-like Carbon and Diamond-like Carbon-Based Nickel Nanocomposite Films Deposited by Reactive Magnetron Sputtering of Ni Target.

Piezoresistive properties of hydrogenated diamond-like carbon (DLC) and DLC-based nickel nanocomposite (DLC:Ni) films were studied in the range of low concentration of nickel nanoparticles. The films were deposited by reactive high power pulsed magnetron sputtering (HIPIMS) of Ni target, and some samples were deposited by direct current (dc) reactive magnetron sputtering for comparison purposes. Raman scattering spectroscopy, energy-dispersive X-ray spectrometry (EDS), and X-ray photoelectron spectroscopy (XPS) were used to study the structure and chemical composition of the films.

Twisted Intramolecular Charge Transfer States in Trinary Star-Shaped Triphenylamine-Based Compounds.

Excited state dynamics of trinary star-shaped dendritic compounds with triphenylamine arms and different cores were studied by means of time-resolved fluorescence and transient absorption. Under optical excitation, nonpolar C symmetry molecules form polar excited states localized on one of the molecular substituents. Conformational excited state stabilization of molecules with an electron-accepting core causes a formation of twisted internal charge transfer (TICT) states in polar solvents.

Diamond like carbon nanocomposites with embedded metallic nanoparticles.

In this work we present an overview on structure formation, optical and electrical properties of diamond like carbon (DLC) based metal nanocomposites deposited by reactive magnetron sputtering and treated by plasma and laser ablation methods. The influence of deposition mode and other technological conditions on the properties of the nanosized filler, matrix components and composition were studied systematically in relation to the final properties of the nanocomposites. Applications of the nanocomposites in the development of novel biosensors combining resonance response of wave guiding structures in DLC based nanocomposites as well as plasmonic effects are also presented.

Scaffold design for artificial tissue with bone marrow stem cells.

Objective: The aim of this study was to test polymeric materials (collagen, fibrin, polyimide film, and polylactic acid) for single- and multi-layer scaffold formation.

Materials And Methods: In our study, we used rabbit bone marrow stem cells (rBMSCs) and human mesenchymal stem cells (hMSCs) with materials of a different origin for the formation of an artificial scaffold, such as a collagen scaffold, fibrin scaffold produced from clotted rabbit plasma, electrospun poly(lactic acid) (PLA) mats, polyimide film (PI), and the combination of the latter two. Cell imaging was performed 3-14 days after cell cultivation in the scaffolds.

Photovoltaic Properties and Ultrafast Plasmon Relaxation Dynamics of Diamond-Like Carbon Nanocomposite Films with Embedded Ag Nanoparticles.

Ultrafast relaxation dynamics of diamond-like carbon (DLC) films with embedded Ag nanoparticles (DLC:Ag) and photovoltaic properties of heterojunctions consisting of DLC:Ag and crystalline silicon (DLC:Ag/Si) were investigated by means of transient absorption (TAS) spectroscopy and photovoltaic measurements. The heterojunctions using both p type and n type silicon were studied. It was found that TAS spectra of DLC:Ag films were dependent on the used excitation wavelength.

Nitrogen-doped twisted graphene grown on copper by atmospheric pressure CVD from a decane precursor.

We present Raman studies of graphene films grown on copper foil by atmospheric pressure CVD with n-decane as a precursor, a mixture of nitrogen and hydrogen as the carrier gas, under different hydrogen flow rates. A novel approach for the processing of the Raman spectroscopy data was employed. It was found that in particular cases, the various parameters of the Raman spectra can be assigned to fractions of the films with different thicknesses.

Femtosecond laser micro-machined polyimide films for cell scaffold applications.

Engineering of sophisticated synthetic 3D scaffolds that allow controlling behaviour and location of the cells requires advanced micro/nano-fabrication techniques. Ultrafast laser micro-machining employing a 1030-nm wavelength Yb:KGW femtosecond laser and a micro-fabrication workstation for micro-machining of commercially available 12.7 and 25.

Micromachining and validation of the scanning acoustic microscope spatial resolution and sensitivity calibration block for 20-230 MHz frequency range.

Scanning acoustic microscopy (SAM) is used as a routine non-destructive test tool for different diagnostic examinations: detection of defects such as microcracks, delamination, disbonding, inclusions, subsurface features in materials such as pores and cracks. SAM can be operated in a wide frequency range from Megahertz to Gigahertz. SAM measurement spatial resolution is diffraction limited by the wavelength of the acoustic wave in particular medium and also depends on individual transducers geometry.

Antimicrobial Properties of Diamond-Like Carbon/Silver Nanocomposite Thin Films Deposited on Textiles: Towards Smart Bandages.

In the current work, a new antibacterial bandage was proposed where diamond-like carbon with silver nanoparticle (DLC:Ag)-coated synthetic silk tissue was used as a building block. The DLC:Ag structure, the dimensions of nanoparticles, the silver concentration and the silver ion release were studied systematically employing scanning electron microscopy, energy dispersive X-ray spectroscopy and atomic absorption spectroscopy, respectively. Antimicrobial properties were investigated using microbiological tests (disk diffusion method and spread-plate technique).

Relevance of HCN2-expressing human mesenchymal stem cells for the generation of biological pacemakers.

Background: The transfection of human mesenchymal stem cells (hMSCs) with the hyperpolarization-activated cyclic nucleotide-gated ion channel 2 (HCN2) gene has been demonstrated to provide biological pacing in dogs with complete heart block. The mechanism appears to be the generation of the ion current (If) by the HCN2-expressing hMSCs. However, it is not clear how the transfection process and/or the HCN2 gene affect the growth functions of the hMSCs.

Numerical and experimental analysis of optical response of sub-wavelength period structure in carbonaceous film for refractive index sensing.

The resonance structure coupling the light into the leaky guided modes, which are visible in the reflection spectra as sharp peaks (Wood's anomalies), is analyzed experimentally and numerically. The guided mode resonance structure of 428 nm period patterned in a carbonaceous film demonstrated sensitivity of 70 nm/RIU. The calculated mode diagram explained the nature and positions of the peaks registered experimentally.