Use Of Nanomaterials Research Articles

Direct observation of morphological transition for an adsorbed single polymer chain

A better understanding of the structure of polymers at solid interfaces is crucial for designing various polymer nano-composite materials from structural materials to nanomaterials for use in industry. To this end, the first step is to obtain information on how synthetic polymer chains adsorb onto a solid surface. We closely followed the trajectory of a single polymer chain on the surface as a function of temperature using atomic force microscopy. Combining the results with a full-atomistic molecular dynamics simulation revealed that the chain became more rigid on the way to reaching a pseudo-equilibrium state, accompanied by a change in its local conformation from mainly loops to trains. This information will be useful for regulating the physical properties of polymers at the interface.

A critical review on nano-food packaging and its applications.

The present manuscript addresses the effect of nanotechnology in various food sectors. Increasedfood functionality, enhanced flavor, reduced delivery of food additives are some of theappealing choices raising plausibility of high health advantages hypothesized in future. At theface of explosion of information, it is important to monitor them in a brief and updated manner.In this manner, new nanomaterials like carbon nanotubes, nano-biopolymers have diverseapplications in food packaging, good food release property with enhanced food safety features.Furthermore, nano-encapsulation of probiotics, nano applications in food processing sector andother related issues, new functional nanomaterials for use in food along with their propertieshave been talked about in this review paper.

Laser-induced Joining of Nanoscale Materials: Processing, Properties, and Applications

• Current progress of laser joining of multidimensional nanomaterials are reviewed. • Laser joining of homogeneous and heterogenous nanomaterials are summarized. • Mechanism of laser nanojoining and practical applications are discussed. • Challenges and directions for future research in laser nanojoining are proposed. The rapid development of flexible and wearable nanodevices for a variety of commercial applications has identified a pressing need for targeted research on nanomaterials for use as building blocks in the fabrication of functional devices via bottom-up assembly. In the search for new fabrication technology, nanojoining or nanowelding has been selected as a promising method in this bottom-up approach. While there are a number of methods that can be used for nanojoining, laser processing is of interest because laser nanojoining combines high-precision property with a flexible manufacturing platform. In this review we discuss how this technology can be implemented in practical applications and outline the advantages and limitations of laser-induced nanojoining. We emphasize how laser nanojoining introduces reliability and reproducibility to the joining process, and show that this is due to precise control over heat-input in nanoscale dimensions. We also review the ways in which laser nanojoining can be integrated with other commercial fabrication operations in practical applications. To illustrate the flexibility of laser nanojoining, we give a detailed summary of joining involving a wide variety of multidimensional heterogeneous nanomaterials in the form of zero-dimension, one-dimension and two-dimension as well as the hybrid combination of these building blocks. We also discuss how laser processing can be used to generate hybrid materials with new functionalities as electrodes for various devices, optical systems and in functional circuits. The mechanisms and strategies in laser-induced joining of nanomaterials are systematically discussed in this paper along with a review of the properties and applications of the joined nanostructures. We also review some challenges in the implementation of this technology and discuss some possible directions for future research into laser-induced nanojoining.

An Uncontrolled Case Series Using a Botanically Derived, β-Cyclodextrin Inclusion Complex in Two Androgenetic Alopecia-Affected Male Subjects

Drug-based monotherapy provides limited clinical benefits in polygenic disorders, such as androgenetic alopecia. Possible benefits must be measured against non-trivial risks of negative side effects. Several well-controlled, peer-reviewed, basic science studies have demonstrated novel mechanisms of action and potential utility for natural-based phytochemicals in the treatment of androgen-mediated disorders, including androgenetic alopecia. Yet, due to phytochemical instability, volatility, and incompatibility, the bridge from in vitro potential to clinical efficacy remains largely unmet. Recent advances in nanomaterial manipulation provide enhanced platforms, such as cyclodextrins, in which these phytochemicals may be enveloped and delivered without triggering the loss of intended function. Unexpected, positive results of an uncontrolled case series for a cyclodextrin-enabled, natural-based formula containing γ linolenic acid, β-Sitosterol, epigallocatechin gallate, and genistein, administered concomitantly via oral and topical form in two androgenetic alopecia-affected, male subjects over the course of 270 days were found. At baseline, significant baldness in the vertex scalp of both subjects was observed. Subsequent 90-day time points demonstrated marked hair thickening. On treatment day 270 (conclusion), scalp hair loss was no longer evident in either patient. Particularly in the setting of a disorders, such as androgenetic alopecia, nano-complexed, botanically-based compositions may offer beneficial adjunctives or alternatives to traditional drug-based/surgical medical treatments.

One-, Two-, and Three-Dimensional Self-Assembly of Atomically Precise Metal Nanoclusters.

Metal nanoclusters (NCs), which consist of several, to about one hundred, metal atoms, have attracted much attention as functional nanomaterials for use in nanotechnology. Because of their fine particle size, metal NCs exhibit physical/chemical properties and functions different from those of the corresponding bulk metal. In recent years, many techniques to precisely synthesize metal NCs have been developed. However, to apply these metal NCs in devices and as next-generation materials, it is necessary to assemble metal NCs to a size that is easy to handle. Recently, multiple techniques have been developed to form one-, two-, and three-dimensional connected structures (CSs) of metal NCs through self-assembly. Further progress of these techniques will promote the development of nanomaterials that take advantage of the characteristics of metal NCs. This review summarizes previous research on the CSs of metal NCs. We hope that this review will allow readers to obtain a general understanding of the formation and functions of CSs and that the obtained knowledge will help to establish clear design guidelines for fabricating new CSs with desired functions in the future.

Size-controlled graphene oxide for highly permeable and fouling-resistant outer-selective hollow fiber thin-film composite membranes for forward osmosis

Size-controlled graphene oxide (SGO) nanosheets, which are uniform and smaller in size than 2 μm, were successfully incorporated into a polyamide (PA) layer for preparing an outer-selective hollow fiber (OSHF) thin-film nanocomposite (TFN) membrane for forward osmosis (FO) applications by vacuum-assisted interfacial polymerization (VAIP). Here, we specifically demonstrate that the SGO nanosheets in amine aqueous solution were horizontally aligned and stacked on the surface of a membrane substrate by vacuum suction from outside to inside in the VAIP; the SGO nanosheets were then well-incorporated into the thin PA layer with less physical damage. In addition, the SGO nanosheets' effective loading inside the PA layer under the VAIP was much higher than that under the typical interfacial polymerization (IP), since there is no issue about the particle loss from air or nitrogen blowing to remove excess amine solution. The benefit would be highly cost-effective in terms of the nanomaterial's use in a TFN membrane production. As a result, the optimum OSHF TFN membrane incorporated with SGO at 0.0005 wt% (SGO5) exhibited outstanding FO performance, including higher water flux at 39.0 L m-2 h-1 and lower specific reverse solute flux at 0.16 g L-1, using a 1 M NaCl draw solution. Furthermore, this study demonstrates the effect of graphene oxide (GO)'s lateral size toward the short water pathway, and GO's stable incorporation and hydrophilicity of the PA thin film. In the fouling test using artificial wastewater, SGO-incorporated membranes exhibited enhanced fouling resistance and cleaning efficiency against the foulant-rich solution. This novel TFN membrane is therefore a good candidate to address FO's challenges for wastewater treatment or desalination.

Application of Carbon Nanotubes(CNT) on The Computer Science and Electrical Engineering:A Review

In recent years, dimensions and sizes of components and parts in the<br />computer and electronic industries have been steadily reducing, as they are<br />now considered very tiny tools and there is always a need to store and<br />process information stronger. Nanotubes have poor magnetic properties. If<br />nanotubes are covered by ferromagnetic nanoparticles, their magnetic<br />properties can be improved and they can be used in the manufacture of<br />nanoelectronic devices in the computer and electronic industries. In addition<br />to reviewing the structure and properties of materials made using different<br />nanomaterials for use in the computer and electronic industries, the present<br />paper aimed to study different applications of nanomaterials, especially<br />carbon nanotubes, in the manufacture of electronic devices. The present<br />study showed that the corporation of nanomaterials into electronic devices is<br />a promising approach for future applications which can revolutionize the<br />computer industry.

Promoting Nanozyme Cascade Bioplatform by ZIF-Derived N-Doped Porous Carbon Nanosheet-based Protein/Bimetallic Nanoparticles for Tandem Catalysis

Nanozymes are a class of nanomaterials with enzyme-like activities that have been extensively studied for their possibilities and superiorities over natural enzymes. Intelligent design and fabrication of a nanozyme platform with highly efficient and stable tandem enzyme characteristics is necessary. Herein, a nanozyme cascade promoting bioplatform based on protein/bimetallic nanoparticles attached to ZIF-derived multilayer N-doped carbon nanosheets is proposed. Due to the carbon-based large surface area and solitary pairs of nitrogen electrons, the metal could be riveted to the carbon-based surface and reduced in situ to nanoparticles. Simultaneously, the addition of BSA has made it possible to establish a biological platform. The obtained BSA-PtAu@CNS has a linear range of 2 × 10-6 to 2 × 10-3 M for H2O2 and apparent dynamic Km of 0.005 × 10-3 M, which shows stronger affinity with H2O2 than HRP. The nanohybrid could adapt to severe reaction environment and enable prominent tandem dual-enzyme activity for glucose sensing. As a result, the cascade nanozyme bioplatform based on BSA-PtAu@CNS is accomplished and provides insights for subsequent biocompatible nanomaterials for use in medical and diagnostic applications.

Method of manufacturing of composite for 3D printing and the electrophysical properties of the obtained material

The present paper presents the technology for the manufacture of filaments based on ABS plastic and Taunit-M nanomaterial for use in 3D printing. A test sample was printed from this filament on a 3D printer using the layered overlap method at 15% Taunit-M content. The transmittance spectra for the printed sample were obtained using a Mach-Zander interferometer in the frequency range 120-260 GHz. The complex dielectric constant of the studied composite was calculated.

Regulation of Neural Stem Cell Proliferation and Differentiation by Graphene-Based Biomaterials.

The transplantation of neural stem cells (NSCs) has become an emerging treatment for neural degeneration. A key factor in such treatments is to manipulate NSC behaviors such as proliferation and differentiation, resulting in the eventual regulation of NSC fate. Novel bionanomaterials have shown usefulness in guiding the proliferation and differentiation of NSCs due to the materials' unique morphological and topological properties. Among the nanomaterials, graphene has drawn increasing attention for neural regeneration applications based on the material's excellent physicochemical properties, surface modifications, and biocompatibility. In this review, we summarize recent works on the use of graphene-based biomaterials for regulating NSC behaviors and the potential use of these materials in clinical treatment. We also discuss the limitations of graphene-based nanomaterials for use in clinical practice. Finally, we provide some future prospects for graphene-based biomaterial applications in neural regeneration.

Optical materials and metamaterials from nanostructured soft matter

Soft materials such as block copolymers, liquid crystals and colloidal assemblies are excellent candidates for use in optical applications due to their ability to spontaneously self-assemble into ordered structures on optically-relevant length scales. Some of these applications rely on optical properties that are intrinsic to the structure and chemical composition of the soft material itself, while others are reliant on the presence of inorganic nanomaterials within the soft material to produce the properties of interest. However, soft materials can be used to generate optical phenomena that originate not just from the intrinsic properties of the nanomaterials, but from their spatial organization as well. In the latter case, exotic optical phenomena such as light focusing beyond the diffraction limit, negative index of refraction and nonlinear photonics appear. These properties originate from the collective response of multiple nanostructures organized to produce an ordered metamaterial. Soft materials, being an excellent medium to convey order on the nanoscale, can be utilized in next generation optical applications to create this kind of organization. Here, we survey how soft matter can be leveraged in optical applications by exploiting self-assembly and directed self-assembly as methods to produce ordered structures with desirable properties. We highlight applications where the soft material is the optically active component, and others where it’s used in tandem with nanomaterials. Specifically, we focus on how soft materials can be used to spatially organize inorganic nanomaterials for use in optical applications where the controlled assembly of such nanomaterials is crucial.

M50 Matrix Sintered with Nanoscale Solid Lubricants Shows Enhanced Self-lubricating Properties Under Dry Sliding at Different Temperatures

Self-lubricating materials have attracted enormous interest from manufacturers and researchers around the world recently to enhance the durability and lifespan of mechanical components. Hence, the high-level objective of this study is to provide insight into how TiO2 and graphene (G) nanomaterials (NMs) could contribute toward enhancing replenishment of the self-lubricating layer on the worn surface of M50 matrix to maintain a supply of solid lubricant. Frictional samples were fabricated by spark plasma sintering (SPS), then their tribological properties against Si3N4 balls were evaluated using a pin-on-disk tribometer at various temperatures. The wear mechanisms of the rubbing surfaces were also elucidated using electron probe microanalysis (EPMA), field-emission scanning electron microscopy (FE-SEM), energy-dispersive spectroscopy (EDS), three-dimensional (3D) surface profilometry, and X-ray photoelectron spectrometry (XPS). The results of the tribotests indicated that M50 manufactured with TiO2 and TiO2/G hybrid NMs presented excellent antifriction/wear properties at temperatures of 25–450 °C, in comparison with the reference material (M50 steel). This is mainly because of the nanoscale solid lubricant added into the M50 microstructure. The results highlight a novel self-lubricating technology for M50 steel sintered with NMs for use in manufacturing of mechanical components for aerospace and automobile engines.

Advances in nanomaterials for use in photothermal and photodynamic therapeutics (Review).

Nanomaterials play crucial roles in the diagnosis and treatment of diseases. Photothermal and photodynamic therapy, as two minimally invasive therapeutic methods, have promising potential in the diagnosis and prevention of cancer. Recently, many photothermal materials (such as noble metal material, transition metal sulfur oxides, carbon material and upconversion nanomaterial) and photodynamic materials (such as phthalein cyanogen, porphyrins and other dye molecules) have been applied in photothermal therapy (PTT) and photodynamic therapy (PDT). Moreover, as nanomaterials have suitable biocompatibility, these materials have been applied in cancer therapy. In the present review, we summarized the effects of different material types, synthesis methods, material morphologies and surface modifications on the outcomes of cancer therapy. The application of nanomaterials in PTT and PDT was introduced and the advantages and disadvantages of PTT and PDT in the prevention of cancer were discussed. Finally, we discussed the application of nanomaterials in the combination of PTT and PDT in cancer treatment.

Plasmonic optical trapping of pyrene-pendant polymer chains by controlling thermophoretic force

Plasmonic optical tweezers (POT) has a high potential for manipulation of nanomaterials due to an enhanced optical force. However, unfavorable thermal effects induced by plasmon excitation have frequently hindered the manipulation. For this issue, we have recently developed a novel non-plasmonic optical tweezers using a nanostructured silicon substrate (B-Si). We called it “Nano-Structured Semi-Conductor-Assisted Optical Tweezers (NASSCA-OT)”. In the present study, we trapped pyrene-pendant polymer chains homogeneously dissolved in water for POT or NASSCA-OT. We used plasmonic gold nanopyramidal dimer arrays or B-Si in contact with the aqueous polymer solution. During plasmon excitation with a near-infrared laser light, any sign of optical trapping was never detected in fluorescence micro-spectroscopy. By contrast, trapping of the polymer chains was obviously observed for NASSCA-OT. Upon laser irradiation, pyrene excimer fluorescence was dramatically increased at the focal spot. These results indicate that NASSCA-OT is a powerful tool for manipulation of molecular materials.

Nano-restructuration of Carbon Materials Under High Temperature Heat Treatment for Environmental Application and Energy Storage

Thermally-induced annealing by furnace in mild conditions and by fast reactor was applied to naphthalene pitch, an amorphous carbon, commercially available. The carbonaceous materials obtained with the two systems were characterized by advanced analytical tools for inferring the occurrence of structural improvements under annealing. The applicability of the produced nanomaterials for use in electrodes preparation for energy storage was discussed.

Magnetic nanoparticles for smart electrochemical immunoassays: a review on recent developments.

This review (with 129 refs) summarizes the progress in electrochemical immunoassays combined with magnetic particles that was made in the past 5years. The specifity of antibodies linked to electrochemical transduction (by amperometry, voltammetry, impedimetry or electrochemiluminescence) gains further attractive features by introducing magnetic nanoparticles (MNPs). This enables fairly easy preconcentration of analytes, minimizes matrix effects, and introduces an appropriate label. Following an introduction into the fundamentals of electrochemical immunoassays and on nanomaterials for respective uses, a large chapter addresses method for magnetic capture and preconcentration of analytes. A next chapter discusses commonly used labels such as dots, enzymes, metal and metal oxide nanoparticles and combined clusters. The large field of hybrid nanomaterials for use in such immunoassays is discussed next, with a focus on MNPs composites with various kinds of graphene variants, polydopamine, noble metal nanoparticles or nanotubes. Typical applications address clinical markers (mainly blood and urine parameters), diagnosis of cancer (markers and cells), detection of pathogens (with subsections on viruses and bacteria), and environmental and food contaminants as toxic agents and pesticides. A concluding section summarizes the present status, current challenges, and highlights future trends. Graphical abstract Magnetic nanoparticles (MNP) with antibodies (Ab) capture and preconcentrate analyte from sample (a) and afterwards become magnetically (b) or immunospecifically (c) bound at anelectrode. Signal either increases due to the presence of alabel (b) or decreases as theredox probe is blocked(c).

Functionalization of Gold Nanoparticles for a Color-Based Detection of Adenosine in a Bioassay

A simple bioassay was designed for the detection of adenosine, a human metabolite involved in several physiological processes, on the basis of the functionalization of gold nanoparticles with DNA oligonucleotides selectively binding adenosine. The test was possible thanks to the selective and sensitive binding of adenosine by two DNA oligonucleotides forming an aptamer. Each DNA strand was grafted on the surface of gold nanoparticles, which formed an insoluble aggregate within a few minutes in the presence of millimolar concentrations of adenosine. The experiments described are suitable for undergraduate and graduate students developing skills in handling and functionalizing nanomaterials for use in biosensors. Besides the handling of nanomaterials, this laboratory training enabled the students to familiarize themselves with the use of nucleic acids in novel techniques, for example, as efficient probes for biosensing purposes.

Influence of fuel nature on dye adsorption efficiency of solution combustion derived zinc oxide nanoparticles: A comparative study

The present work demonstrates the use of coffee husk extract as a fuel (otherwise an agro waste) for the synthesis of nano zinc oxide (ZnO) by one step solution combustion synthesis. We also show the comparative studies of coffee husk extract (green fuel) derived nano ZnO (CHZnO) and sugar (chemical fuel) derived nano ZnO (SZnO) as an adsorbent for Congo red dye removal. Synthesized ZnO nanoparticles were characterized using XRD, SEM, TEM, FTIR, and BET. The adsorption characteristics were investigated with respect to changes in pH, temperature, initial dye concentration, adsorbent dose and contact time. CHZnO exhibited higher adsorption capacity (76 mg g−1) compared to SZnO (56 mg g−1). The equilibrium adsorption data were analyzed using various isotherm models (Langmuir, Freundlich, Temkin, and Dubinin-Radushkevith) and thermodynamic parameters. Among the models studied, Langmuir isotherm fitted well with experimental equilibrium data (R2 > 0.99). Adsorption kinetics was found to follow pseudo-second order with the highest R2 value. Intraparticle or pore diffusion was the major rate controlling step in the adsorption process. The present study demonstrates the potential application of agro-based bio-waste as a novel fuel in the synthesis of nanomaterials for use as efficient adsorbents in water treatment.

N-doped carbon-coated Tin sulfide/graphene nanocomposite for enhanced lithium storage

Tin sulfides have attracted significant interests as the anode materials of lithium-ion batteries (LIBs) due to their high capacity and layered structure. However, metal sulfides suffer from a fast capacity decay caused by the large volume change during cycling, and poor conductivity. In this work, we report on a rational design of lamellar nanostructure consisting of N-doped carbon layers, graphene nanosheets, and SnS nanoparticles. The SnS/graphene nanosheets with and without N-carbon coating have been investigated as the anode for LIBs to study the structure effect. It is found that N-carbon/SnS/graphene nanosheets deliver a high reversible capacity of 840 mA h g−1 after 150 cycles at a current density of 100 mA g−1 and higher rate properties in comparison to SnS/graphene. The improved electrochemical performances are attributed to the special lamellar structure with a combined synergic effect derived from the N-carbon coating layers and graphene nanosheets, which conduce to a faster lithium diffusion dynamics in the composite nanosheets, which has been analyzed by electrochemical impedance spectroscopy. This work propose an efficient pathway to manipulate metal sulfides based nanomaterials for use as anodes in LIBs with enhanced lithium storage performances.

Phytic acid functionalized Fe3O4 nanoparticles loaded with Ti(IV) ions for phosphopeptide enrichment in mass spectrometric analysis.

A novel magnetic nanomaterial for use in metal ion based affinity chromatography is described. It is based on the chelation between the phosphate groups of phytic acid (PA) and Ti(IV) ions. Due to the large number (6) of phosphate groups of PA, it has a large capacity for Ti(IV) ions. PA was first immobilized on magnetite nanoparticles (PA-MNPs) and then loaded with Ti(IV) ions to obtain the sorbent (Ti-PA-MNPs). The fraction of Ti(IV) ions on the surface of PA-MNPs that is exposed to the solution binds the phosphate groups of phosphopeptides. The bound phosphopeptides can then be magnetically separated. The method was applied to the enrichment of the phosphopeptides in a β-casein tryptic digest. A tryptic digest of bovine serum albumin (BSA) was added at a molar ratio (β-casein to BSA) of 1:2000 to study selectivity. The phosphopeptides were quantified by mass spectrometry. The limit of detection can be as low as 8 × 10-10molL-1. This sorbent has a high absorption capacity (53.5μgmg-1) and shows good recoveries (90%). As many as 2145 phosphopeptides were isolated from 500μg tryptic digest of a rat liver lysate after enrichment by Ti-PA-MNPs. This is superior to that (1568 phosphopeptides) of commercial TiO2 kit. Graphical abstract Schematic presentation of fabrication for a novel modified magnetic nanomaterial (Ti-PA-MNPs) based on the chelation of phytic acid (PA) with Ti(IV) ions. Ti-PA-MNPs were successfully applied to enriching low abundance phosphopeptides from biosamples in mass spectrometric analysis.