Research

10 pages, 51981 KiB

Open AccessArticle

Study on the Physical Properties of a SiNW Biosensor to the Sensitivity of DNA Detection

by Siti Noorhaniah Yusoh and Khatijah Aisha Yaacob

Materials 2021, 14(19), 5716; https://doi.org/10.3390/ma14195716 - 30 Sep 2021

Cited by 2 | Viewed by 1192

SiNW (silicon nanowire) arrays consisting of 5- and 10-wires were fabricated by using an atomic force microscope—the local anodic oxidation (AFM-LAO) technique followed by wet chemical etching. Tetramethylammonium hydroxide (TMAH) and isopropyl alcohol (IPA) at various concentrations were used to etch SiNWs. The [...] Read more.

SiNW (silicon nanowire) arrays consisting of 5- and 10-wires were fabricated by using an atomic force microscope—the local anodic oxidation (AFM-LAO) technique followed by wet chemical etching. Tetramethylammonium hydroxide (TMAH) and isopropyl alcohol (IPA) at various concentrations were used to etch SiNWs. The SiNWs produced were differed in dimension and surface roughness. The SiNWs were functionalized and used for the detection of deoxyribonucleic acid (DNA) dengue (DEN-1). SiNW-based biosensors show sensitive detection of dengue DNA due to certain factors. The physical properties of SiNWs, such as the number of wires, the dimensions of wires, and surface roughness, were found to influence the sensitivity of the biosensor device. The SiNW biosensor device with 10 wires, a larger surface-to-volume ratio, and a rough surface is the most sensitive device, with a 1.93 fM limit of detection (LOD). Full article

(This article belongs to the Special Issue Advances in Nanostructured Materials)

► Show Figures

Figure 1

19 pages, 3884 KiB

Open AccessArticle

Particle Size Measurement Using Dynamic Light Scattering at Ultra-Low Concentration Accounting for Particle Number Fluctuations

by Mengjie Wang, Jin Shen, John C. Thomas, Tongtong Mu, Wei Liu, Yajing Wang, Jinfeng Pan, Qin Wang and Kaishi Liu

Materials 2021, 14(19), 5683; https://doi.org/10.3390/ma14195683 - 29 Sep 2021

Cited by 9 | Viewed by 2614

Abstract

Dynamic light scattering (DLS) is a popular method of particle size measurement, but at ultra-low particle concentrations, the occurrence of number concentration fluctuations limits the use of the technique. Number fluctuations add a non-Gaussian term to the scattered light intensity autocorrelation function (ACF). [...] Read more.

Dynamic light scattering (DLS) is a popular method of particle size measurement, but at ultra-low particle concentrations, the occurrence of number concentration fluctuations limits the use of the technique. Number fluctuations add a non-Gaussian term to the scattered light intensity autocorrelation function (ACF). This leads to an inaccurate particle size distribution (PSD) being recovered if the normal DLS analysis model is used. We propose two methods for inverting the DLS data and recovering the PSDs when number fluctuations are apparent. One is to directly establish the relationship between the non-Gaussian ACF and the PSD by the kernel function reconstruction (KFR) method while including the non-Gaussian term to recover the PSD. The other is to remove the effect of the non-Gaussian term in the ACF by the baseline reset (BR) method. By including the number fluctuation term, the ideal recovered PSD can be obtained from the simulated data, but this will not happen in the experimental measurement data. This is because the measured intensity ACF contains more noise than the simulated ACF at ultra-low concentration. In particular, the baseline noise at the tail of long delay time of ACF overwhelms the number fluctuation term, making it difficult to recover reliable PSD data. Resetting the baseline can effectively remove the digital fluctuation term in ACF, which is also a feasible method to improve PSD recovery under ultra-low concentration. However, increasing noise at ultra-low concentrations can lead to errors in determining an effective baseline. This greatly reduces the accuracy of inversion results. Results from simulated and measured ACF data show that, for both methods, noise on the ACF limits reliable PSD recovery. Full article

(This article belongs to the Special Issue Advances in Nanostructured Materials)

► Show Figures

Figure 1

14 pages, 1656 KiB

Open AccessFeature PaperArticle

Evaluation of PC12 Cells’ Proliferation, Adhesion and Migration with the Use of an Extracellular Matrix (CorMatrix) for Application in Neural Tissue Engineering

by Katarzyna Gębczak, Benita Wiatrak and Wojciech Fortuna

Materials 2021, 14(14), 3858; https://doi.org/10.3390/ma14143858 - 10 Jul 2021

Cited by 2 | Viewed by 2252 | Correction

Abstract

The use of extracellular matrix (ECM) biomaterials for soft tissue repair has proved extremely successful in animal models and in some clinical settings. The aim of the study was to investigate the effect of the commercially obtained CorMatrix bioscaffold on the viability, proliferation [...] Read more.

The use of extracellular matrix (ECM) biomaterials for soft tissue repair has proved extremely successful in animal models and in some clinical settings. The aim of the study was to investigate the effect of the commercially obtained CorMatrix bioscaffold on the viability, proliferation and migration of rat pheochromocytoma cell line PC12. PC12 cells were plated directly onto a CorMatrix flake or the well surface of a 12-well plate and cultured in RPMI-1640 medium and a medium supplemented with the nerve growth factor (NGF). The surface of the culture plates was modified with collagen type I (Col I). The number of PC12 cells was counted at four time points and then analysed for apoptosis using a staining kit containing annexin V conjugate with fluorescein and propidium iodide (PI). The effect of CorMatrix bioscaffold on the proliferation and migration of PC12 cells was tested by staining the cells with Hoechst 33258 solution for analysis using fluorescence microscopy. The research showed that the percentage of apoptotic and necrotic cells was low (less than 7%). CorMatrix stimulates the proliferation and possibly migration of PC12 cells that populate all levels of the three-dimensional architecture of the biomaterial. Further research on the mechanical and biochemical capabilities of CorMatrix offers prospects for the use of this material in neuro-regenerative applications. Full article

(This article belongs to the Special Issue Advances in Nanostructured Materials)

► Show Figures

Figure 1

19 pages, 3522 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Upconversion Luminescence of Silica–Calcia Nanoparticles Co-doped with Tm³⁺ and Yb³⁺ Ions

by Katarzyna Halubek-Gluchowska, Damian Szymański, Thi Ngoc Lam Tran, Maurizio Ferrari and Anna Lukowiak

Materials 2021, 14(4), 937; https://doi.org/10.3390/ma14040937 - 16 Feb 2021

Cited by 23 | Viewed by 3044

Abstract

Looking for upconverting biocompatible nanoparticles, we have prepared by the sol–gel method, silica–calcia glass nanopowders doped with different concentration of Tm³⁺ and Yb³⁺ ions (Tm³⁺ from 0.15 mol% up to 0.5 mol% and Yb³⁺ from 1 mol% up to [...] Read more.

Looking for upconverting biocompatible nanoparticles, we have prepared by the sol–gel method, silica–calcia glass nanopowders doped with different concentration of Tm³⁺ and Yb³⁺ ions (Tm³⁺ from 0.15 mol% up to 0.5 mol% and Yb³⁺ from 1 mol% up to 4 mol%) and characterized their structure, morphology, and optical properties. X-ray diffraction patterns indicated an amorphous phase of the silica-based glass with partial crystallization of samples with a higher content of lanthanides ions. Transmission electron microscopy images showed that the average size of particles decreased with increasing lanthanides content. The upconversion (UC) emission spectra and fluorescence lifetimes were registered under near infrared excitation (980 nm) at room temperature to study the energy transfer between Yb³⁺ and Tm³⁺ at various active ions concentrations. Characteristic emission bands of Tm³⁺ ions in the range of 350 nm to 850 nm were observed. To understand the mechanism of Yb³⁺–Tm³⁺ UC energy transfer in the SiO₂–CaO powders, the kinetics of luminescence decays were studied. Full article

(This article belongs to the Special Issue Advances in Nanostructured Materials)

► Show Figures

Figure 1

13 pages, 42524 KiB

Open AccessArticle

Non-Iridescent Metal Nanomesh with Disordered Nanoapertures Fabricated by Phase Separation Lithography of Polymer Blend as Transparent Conductive Film

by Xinyu Chen, Yuting He, Xiaofeng Chen, Chunyu Huang, Yang Li, Yushuang Cui, Changsheng Yuan and Haixiong Ge

Materials 2021, 14(4), 867; https://doi.org/10.3390/ma14040867 - 11 Feb 2021

Cited by 6 | Viewed by 1710

Abstract

Metallic nanomesh, one of the emerging transparent conductive film (TCF) materials with both high electrical conductivity and optical transmittance, shows great potential to replace indium tin oxide (ITO) in optoelectronic devices. However, lithography-fabricated metallic nanomeshes suffer from an iridescence problem caused by the [...] Read more.

Metallic nanomesh, one of the emerging transparent conductive film (TCF) materials with both high electrical conductivity and optical transmittance, shows great potential to replace indium tin oxide (ITO) in optoelectronic devices. However, lithography-fabricated metallic nanomeshes suffer from an iridescence problem caused by the optical diffraction of periodic nanostructures, which has negative effects on display performance. In this work, we propose a novel approach to fabricate large-scale metallic nanomesh as TCFs on flexible polyethylene terephthalate (PET) sheets by maskless phase separation lithography of polymer blends in a low-cost and facile process. Polystyrene (PS)/polyphenylsilsequioxane (PPSQ) polymer blend was chosen as resist material for phase separation lithography due to their different etching selectivity under O₂ reactive ion etching (RIE). The PS constituent was selectively removed by O₂ RIE and the remained PPSQ nanopillars with varying sizes in random distribution were used as masks for further pattern transfer and metal deposition process. Gold (Au) nanomeshes with adjustable nanostructures were achieved after the lift-off step. Au nanomesh exhibited good optoelectronic properties (R_S = 41 Ω/sq, T = 71.9%) and non-iridescence, without angle dependence owing to the aperiodic structures of disordered apertures. The results indicate that this Au nanomesh has high potential application in high-performance and broad-viewing-angle optoelectronic devices. Full article

(This article belongs to the Special Issue Advances in Nanostructured Materials)

► Show Figures

Figure 1

23 pages, 9603 KiB

Open AccessArticle

Optical, Structural, and Dielectric Properties of Composites Based on Thermoplastic Polymers of the Polyolefin and Polyurethane Type and BaTiO₃ Nanoparticles

by M. Baibarac, A. Nila, I. Smaranda, M. Stroe, L. Stingescu, M. Cristea, R. C. Cercel, A. Lorinczi, P. Ganea, I. Mercioniu, R. Ciobanu, C. Schreiner, R. G. Garcia and C. Bartha

Materials 2021, 14(4), 753; https://doi.org/10.3390/ma14040753 - 05 Feb 2021

Cited by 11 | Viewed by 2667

Abstract

In this work, new films containing composite materials based on blends of thermoplastic polymers of the polyurethane (TPU) and polyolefin (TPO) type, in the absence and presence of BaTiO₃ nanoparticles (NPs) with the size smaller 100 nm, were prepared. The vibrational properties [...] Read more.

In this work, new films containing composite materials based on blends of thermoplastic polymers of the polyurethane (TPU) and polyolefin (TPO) type, in the absence and presence of BaTiO₃ nanoparticles (NPs) with the size smaller 100 nm, were prepared. The vibrational properties of the free films depending on the weight ratio of the two thermoplastic polymers were studied. Our results demonstrate that these films are optically active, with strong, broad, and adjustable photoluminescence by varying the amount of TPU. The crystalline structure of BaTiO₃ and the influence of thermoplastic polymers on the crystallization process of these inorganic NPs were determined by X-ray diffraction (XRD) studies. The vibrational changes induced in the thermoplastic polymer’s matrix of the BaTiO₃ NPs were showcased by Raman scattering and FTIR spectroscopy. The incorporation of BaTiO₃ NPs in the matrix of thermoplastic elastomers revealed the shift dependence of the photoluminescence (PL) band depending on the BaTiO₃ NP concentration, which was capable of covering a wide visible spectral range. The dependencies of the dielectric relaxation phenomena with the weight of BaTiO₃ NPs in thermoplastic polymers blends were also demonstrated. Full article

(This article belongs to the Special Issue Advances in Nanostructured Materials)

► Show Figures

Figure 1

11 pages, 5138 KiB

Open AccessArticle

Electrochemical Recovery and Behaviors of Rare Earth (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb) Ions on Ni Sheets

by Min Hee Joo, So Jeong Park, Sung Min Hong, Choong Kyun Rhee and Youngku Sohn

Materials 2020, 13(23), 5314; https://doi.org/10.3390/ma13235314 - 24 Nov 2020

Cited by 17 | Viewed by 2371

Abstract

The electrochemical behaviors of rare earth (RE) ions have extensively been studied because of their high potential applications to the reprocessing of used nuclear fuels and RE-containing materials. In the present study, we fully investigated the electrochemical behaviors of RE(III) (La, Ce, Pr, [...] Read more.

The electrochemical behaviors of rare earth (RE) ions have extensively been studied because of their high potential applications to the reprocessing of used nuclear fuels and RE-containing materials. In the present study, we fully investigated the electrochemical behaviors of RE(III) (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb) ions over a Ni sheet electrode in 0.1 M NaClO₄ electrolyte solution by cyclic voltammetry between +0.5 and −1.5 V (vs. Ag/AgCl). Amperometry electrodeposition experiments were performed between −1.2 and −0.9 V to recover RE elements over the Ni sheet. The successfully RE-recovered Ni sheets were fully characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and photoluminescence spectroscopy. The newly reported recovery data for RE(III) ions over a metal electrode provide valuable information on the development of the treatment methods of RE elements. Full article

(This article belongs to the Special Issue Advances in Nanostructured Materials)

► Show Figures

Figure 1

13 pages, 3224 KiB

Open AccessArticle

Robust Metallic Nanolaminates Having Phonon-Glass Thermal Conductivity

by Francisco Alfredo García-Pastor, Josué Benjamín Montelongo-Vega, Marco Vinicio Tovar-Padilla, María Antonia Cardona-Castro and Jaime Alvarez-Quintana

Materials 2020, 13(21), 4954; https://doi.org/10.3390/ma13214954 - 04 Nov 2020

Cited by 3 | Viewed by 1576

Abstract

Heat transfer phenomena in multilayer structures have gained interest due to their promising use in thermal insulation and thermoelectricity applications. In such systems, nanostructuring has been used to introduce moderate interfacial density, and it has been demonstrated that interfacial thermal resistance plays a [...] Read more.

Heat transfer phenomena in multilayer structures have gained interest due to their promising use in thermal insulation and thermoelectricity applications. In such systems, nanostructuring has been used to introduce moderate interfacial density, and it has been demonstrated that interfacial thermal resistance plays a crucial role in reducing thermal conductivity κ. Nevertheless, the main constraint for actual applications is related to their tiny size because they are extremely thin to establish appreciable temperature gradients. In this work, by severe plastic deformation process of accumulative roll bonding (ARB), a 250 µm thick Cu-Nb multilayer containing more than 8000 interfaces with periods below 40 nm was obtained, enabling the production of bulk metallic nanolaminates with ultralow κ. Multilayers present an ultralow κ of ∼0.81 W/mK at 300 K, which is 100 times smaller than its Cu-Nb bulk counterpart, and even lower than the amorphous lattice limit for the Cu-Nb thin film system. By using electron diffusive mismatch model (EDMM), we argue that both electrons diffusively scattering at interface and those ballistically crossing the constituents are responsible for heat conduction in the Cu-Nb multilayers at nanoscale. Hence, ARB Cu-Nb multilayers are intriguing candidate materials which can prove avenues to achieve stable ultralow κ thermal barriers for robust applications. Full article

(This article belongs to the Special Issue Advances in Nanostructured Materials)

► Show Figures

Figure 1

10 pages, 3710 KiB

Open AccessArticle

A Facile Synthesis and Characterization of Highly Crystalline Submicro-Sized BiFeO₃

by Dovydas Karoblis, Diana Griesiute, Kestutis Mazeika, Dalis Baltrunas, Dmitry V. Karpinsky, Anna Lukowiak, Pawel Gluchowski, Rimantas Raudonis, Arturas Katelnikovas, Aleksej Zarkov and Aivaras Kareiva

Materials 2020, 13(13), 3035; https://doi.org/10.3390/ma13133035 - 07 Jul 2020

Cited by 16 | Viewed by 2660

Abstract

In this study, a highly crystalline bismuth ferrite (BFO) powder was synthesized using a novel, very simple, and cost-effective synthetic approach. It was demonstrated that the optimal annealing temperature for the preparation of highly-pure BFO is 650 °C. At lower or higher temperatures, [...] Read more.

In this study, a highly crystalline bismuth ferrite (BFO) powder was synthesized using a novel, very simple, and cost-effective synthetic approach. It was demonstrated that the optimal annealing temperature for the preparation of highly-pure BFO is 650 °C. At lower or higher temperatures, the formation of neighboring crystal phases was observed. The thermal behavior of BFO precursor gel was investigated by thermogravimetric and differential scanning calorimetry (TG-DSC) measurements. X-ray diffraction (XRD) analysis and Mössbauer spectroscopy were employed for the investigation of structural properties. Scanning electron microscopy (SEM) was used to evaluate morphological features of the synthesized materials. The obtained powders were also characterized by magnetization measurements, which showed antiferromagnetic behavior of BFO powders. Full article

(This article belongs to the Special Issue Advances in Nanostructured Materials)

► Show Figures

Graphical abstract

14 pages, 3443 KiB

Open AccessArticle

Graphene Oxide Carboxymethylcellulose Nanocomposite for Dressing Materials

by Maria Luisa Saladino, Marta Markowska, Clara Carmone, Patrizia Cancemi, Rosa Alduina, Alessandro Presentato, Roberto Scaffaro, Dariusz Biały, Mariusz Hasiak, Dariusz Hreniak and Magdalena Wawrzyńska

Materials 2020, 13(8), 1980; https://doi.org/10.3390/ma13081980 - 23 Apr 2020

Cited by 31 | Viewed by 3980

Abstract

Sore, infected wounds are a major clinical issue, and there is thus an urgent need for novel biomaterials as multifunctional constituents for dressings. A set of biocomposites was prepared by solvent casting using different concentrations of carboxymethylcellulose (CMC) and exfoliated graphene oxide ( [...] Read more.

Sore, infected wounds are a major clinical issue, and there is thus an urgent need for novel biomaterials as multifunctional constituents for dressings. A set of biocomposites was prepared by solvent casting using different concentrations of carboxymethylcellulose (CMC) and exfoliated graphene oxide (Exf-GO) as a filler. Exf-GO was first obtained by the strong oxidation and exfoliation of graphite. The structural, morphological and mechanical properties of the composites (CMCx/Exf-GO) were evaluated, and the obtained composites were homogenous, transparent and brownish in color. The results confirmed that Exf-GO may be homogeneously dispersed in CMC. It was found that the composite has an inhibitory activity against the Gram-positive Staphylococcus aureus, but not against Gram-negative Pseudomonas aeruginosa. At the same time, it does not exhibit any cytotoxic effect on normal fibroblasts. Full article

(This article belongs to the Special Issue Advances in Nanostructured Materials)

► Show Figures

Figure 1

12 pages, 4117 KiB

Open AccessArticle

Magnetic Properties of La_0.9A_0.1MnO₃ (A: Li, Na, K) Nanopowders and Nanoceramics

by Paweł Głuchowski, Ruslan Nikonkov, Robert Tomala, Wiesław Stręk, Tatsiana Shulha, Maria Serdechnova, Mikhail Zheludkevich, Andrius Pakalaniškis, Ramūnas Skaudžius, Aivaras Kareiva, Alexander Abramov, Andrei Kholkin, Maxim V. Bushinsky and Dmitry Karpinsky

Materials 2020, 13(7), 1788; https://doi.org/10.3390/ma13071788 - 10 Apr 2020

Cited by 6 | Viewed by 3069

Abstract

Nanocrystalline La_0.9A_0.1MnO₃ (where A is Li, Na, K) powders were synthesized by a combustion method. The powders used to prepare nanoceramics were fabricated via a high-temperature sintering method. The structure and morphology of all compounds were characterized by [...] Read more.

Nanocrystalline La_0.9A_0.1MnO₃ (where A is Li, Na, K) powders were synthesized by a combustion method. The powders used to prepare nanoceramics were fabricated via a high-temperature sintering method. The structure and morphology of all compounds were characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). It was found that the size of the crystallites depended on the type of alkali ions used. The high-pressure sintering method kept the nanosized character of the grains in the ceramics, which had a significant impact on their physical properties. Magnetization studies were performed for both powder and ceramic samples in order to check the impact of the alkali ion dopants as well as the sintering pressure on the magnetization of the compounds. It was found that, by using different dopants, it was possible to strongly change the magnetic characteristics of the manganites. Full article

(This article belongs to the Special Issue Advances in Nanostructured Materials)

► Show Figures

Figure 1

15 pages, 7030 KiB

Open AccessArticle

Effect of Porous Structure on the Microwave Absorption Capacity of Soft Magnetic Connecting Network Ni/Al₂O₃/Ni Film

by Hu Wei, Li Cheng and Dmitry Shchukin

Materials 2020, 13(7), 1764; https://doi.org/10.3390/ma13071764 - 09 Apr 2020

Cited by 9 | Viewed by 2964

Abstract

Microwave radar absorbing materials have been the focus of the radar stealth research field. In this study, ceramic structured porous honeycomb-like Al₂O₃ film was prepared by anodic oxidation, and an Ni layer was deposited on the Al₂O₃ [...] Read more.

Microwave radar absorbing materials have been the focus of the radar stealth research field. In this study, ceramic structured porous honeycomb-like Al₂O₃ film was prepared by anodic oxidation, and an Ni layer was deposited on the Al₂O₃ film via electrodeposition in a neutral environment to form a flower- and grain-like structure in a three-dimensional (3D) network Ni/Al₂O₃/Ni film. The films both have a through-hole internal structure, soft magnetic properties, and absorb microwaves. The dielectric loss values of two films were little changed, and the maximum microwave absorption values of flower- and grain-like Ni/Al₂O₃/Ni film were −45.3 and −31.05 dB with relatively wide effective bandwidths, respectively. The porous ceramic structure Al₂O₃ interlayer prevented the reunion of Ni and isolated the eddy current to improve the microwave absorption properties. The material presented in our paper has good microwave absorption performance with a thin thickness, which indicates the potential for lightweight and efficient microwave absorption applications. Full article

(This article belongs to the Special Issue Advances in Nanostructured Materials)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Advances in Nanostructured Materials

Share This Special Issue

Special Issue Editors

Special Issue Information

Keywords

Published Papers (12 papers)

Research

Further Information

Guidelines

MDPI Initiatives

Follow MDPI