Nanowerk Nanotechnology Spotlight

Defining the immunological effects of nucleic acid nanoparticles

Mon, 25 Jun 2018 11:24:52 -0400

Programmable nucleic acid nanoparticle (NANP) technology is a relatively new field that has already given rise to a host of self-assembling nucleic acid nanoparticles that are increasingly viewed as promising biological materials for medical applications. Programmable self-assembling NANPs are amenable to chemical modifications, control over functionalization, and consistent batch-to-batch formulation. Researchers present the first detailed and systematic study that involved 25 most representative NANPs, originally designed by different groups, screened for the induction of 29 different cytokines.

Flexible, implantable nutrient sensors based on metal-organic frameworks

Thu, 21 Jun 2018 07:27:14 -0400

Researchers have demonstrated materials and techniques to achieve highly sensitive flexible biosensors integrated with metal-organic frameworks (MOFs) - essentially inorganic-organic hybrids that contain repeated metal ions connected with organic ligands. These high-throughput flexible devices can achieve highly specific and sensitive electrochemical detection and can be used to monitor neurotransmitters and nutrients in vivo.

Cell membrane coating as a platform nanotechnology for medicine

Thu, 21 Jun 2018 07:23:24 -0400

Cell membrane coating is a platform technology that presents a facile top-down method for designing nanocarriers with surfaces that directly replicate the highly complex functionalities necessary for effective biointerfacing. This new class of biomimetic nanoparticles combines the advantages of both natural and artificial nanomaterials. Cell membrane-coated nanoparticles are characterized by a synthetic nanoparticulate core cloaked by a layer of natural cell membrane.

Addressing the hazard potential of 2D nanomaterials

Tue, 19 Jun 2018 09:36:00 -0400

A new paper reviews the studies to date that have addressed the toxicity of 2D materials, particularly emphasizing the preparation methods and resulting physicochemical properties that dictate their interactions with biological systems. In addition, due to its importance in determining exposure risk, this review summarizes key results from the literature concerning the environmental fate of 2D materials. The authors hope that a thorough understanding of these issues will inform ongoing efforts to realize the design of safer 2D materials.

Piezoelectric nanogenerators made from spider silk

Thu, 14 Jun 2018 02:04:14 -0400

Spider silk fibers show nature's most outstanding mechanical properties, for example, excellent tensile strength and elasticity, and remarkable protein sequence structure. So far, it has remained completely unidentified how the mechanical properties of spider silk fibers effectively contribute to the performance of a piezoelectric nanogenerator. Now, researchers have successfully demonstrated by Piezoresponse Force Microscopy experiment that natural spider silk fibers have a definite vertical (out-of-plane) piezoelectric coefficient.

Eggshell membranes from bio waste could be harvesters for green energy

Tue, 12 Jun 2018 10:21:39 -0400

In new work, researchers explore inexpensive, biodegradable and daily-waste eggshell membrane as a novel bio-piezoelectric material for harvesting green energy. The uniqueness of our work lies in the novelty of directly utilizing natural eggshell membranes as efficient piezoelectric material. This simple, innovative approach could provide huge benefits for research in future energy science, especially with regard to in vivo biomedical applications.

Potential nanotechnology applications in combating opioid drug abuse

Fri, 01 Jun 2018 11:01:35 -0400

Drug abuse and dependence/addiction are complex disorders that are regulated by a wide range of interacting networks of genes and pathways that control a variety of phenotypes. Therefore, both identification of the at-risk population and treatment of the addiction disorders are strongly reliant on the development of new and innovative approaches for understanding the mechanisms underlying drug dependency and addiction. There are potential capacities of nanotechnology for the field of drug dependency and addiction.

Microfluidics meets silver nanowires: transparent and flexible circuits with ultra precise pattern control

Thu, 31 May 2018 02:21:51 -0400

Researchers have developed a new process for completely transparent and flexible circuits of any patterns as one wishes. The circuit patterns are created via the well-developed microfluidic technology on transparent and flexible substrates. The conductors are generated by spin coating of silver nanowires along the patterns. The advance stimulates more implications in future electronics. The researchers have demonstrated a simple application of the circuits as a biosensor for glucose detection.

Turning hair into a biomedical nanomaterial

Wed, 30 May 2018 07:55:55 -0400

Scientists have discovered that the hierarchical micro- and nanostructures of human hair can be turned into hierarchical micro- and nanoparticles with a simple top-down procedure and be used as a novel type of biomaterial for medical applications. This strategy of preparing biomaterials from abundant human hair might provide a potent tool for producing autogenous materials from patients themselves to overcome the drawbacks of synthetic materials.

Transparent graphene implant for deep brain imaging and optogenetics

Thu, 24 May 2018 13:25:52 -0400

Although advances in optical technologies such as multi-photon microscopy and optogenetics have revolutionized researchers' ability to record and manipulate neuronal activity, integration of optical modalities with electrical recordings is challenging due to generation of light-induced artifacts. In new work, scientists report a transparent graphene microelectrode neural implant that eliminates light-induced artifacts to enable crosstalk-free integration of 2-photon microscopy, optogenetic stimulation, and cortical recordings in the same in vivo experiment.

Moisture-powered electronics

Wed, 23 May 2018 04:31:25 -0400

Very different from piezoelectric and other energy harvesting technologies, new research shows that water vapor or moisture expand the range of natural phenomena that can be used to generate electric power. Researchers demonstrate that moisture, a vast kind of resource existing ubiquitously on earth and in biological organisms, can be exploited as a novel harvestable energy to generate electricity. Although some device configurations previously have been demonstrated to directly generate electricity from moisture, these generators have not been shown yet to be flexible and to be used as self-powered wearable devices.

Nature-inspired nanotechnology: skin-mimicking sensors

Tue, 22 May 2018 08:21:17 -0400

Mimicking the exciting skin structure and function, researchers have designed hierarchical nanoporous and interlocked micro ridge structured polymers with gradient stiffness. The gradient elastic modulus of interlocked and micro ridge structured polymers effectively transfers the external stress and induces the large frictional contact between two polymeric layers, which facilitates their use in self-powered triboelectric sensors. Furthermore, the additional nanoporous structures in the micro ridge structured polymers lead to the effective variation of both volume and gap distance between opposing surfaces without the need of bulky spacers, resulting in ultrathin and flexible triboelectric sensors for applications in wearable electronics.

Designing safer metal oxide nanoparticles

Fri, 18 May 2018 02:19:08 -0400

Significant bioaccumulation of nanomaterials in the liver via inadvertent or systemic exposure, as well as the lack of a mechanistic knowledge that describes the hazard potential of metal oxide nanoparticles in liver cells, prompted researchers to comprehensively explore metal oxide nanoparticle interactions with major liver cells, including phagocytic cells and hepatocytes. They now report on the assessment of the toxicity of 29 metal oxide nanoparticles in liver macrophages (Kupffer cells) and hepatocytes.

A full gamut of colors in all-dielectric, cheap, and large-scale artificial butterfly wings

Fri, 11 May 2018 11:32:18 -0400

Most approaches to making artificial structural colors rely on low-throughput fabrication techniques, use expensive noble metal materials, and are limited to microscopic footprints. To address these limitations, an international team of researchers has demonstrated high-throughput fabrication of all-dielectric mesoporous materials with macroscopic footprints and colorimetric signatures spanning the whole gamut of visible colors. Inspired by the butterfly wing coloration, the researchers completely avoided the use of noble metals, and instead realized structural colors in cheap and abundant dielectric materials, which are completely transparent in the bulk form.

Studying strain effects in 2D materials using Kelvin Probe Microcopy

Wed, 09 May 2018 02:03:50 -0400

At the nanoscale, materials become exceedingly sensitive to external perturbations. This is quite a relevant factor for wearable and flexible applications, where materials would always bear a certain degree of variable strain/stress. So far it has been very difficult to characterize strain effects in 2D materials, which is crucial to understanding strain-matter interactions. Researchers demonstrate that this limitation can be overcome by using a technique based on Kelvin Probe Microcopy.

High-performance graphene sheets for engineering high-tech materials

Tue, 08 May 2018 04:50:50 -0400

Today, the common engineering solution to manufacture carbon fiber reinforced plastic composite materials is based on cross-plied carbon fibers in a polymer resin requiring high temperature cure. In contrast, researchers now have demonstrated cross-linked graphene sheets that are manufacturable from graphene platelets, which are resin-free, processable at low temperature, and contain less than 10 wt.% additives. This advance provides a universal strategy for converting inexpensive graphene platelets into high performance polymer-free graphene sheets for the development of next-generation lightweight multifunctional materials.

A smart skin for marine biology research

Mon, 07 May 2018 01:44:25 -0400

Frequently, research by marine biologists depends on weighty and invasive sensory and telemetry equipment to understand and assess various aspects of the marine ecosystem. Researchers generally employ invasive attachment techniques to attach these devices to animals, sometimes restricting their natural movements. These tagging systems can be quite abrasive and not so forgiving on the animals. An alternative is a newly developed developed smart skin that integrates the main desired sensor arrays for continuously logging salinity/conductivity, temperature and depth in deep oceans.

All-natural nanobiotechnology instead of synthetic agrochemicals

Fri, 04 May 2018 03:40:45 -0400

Widespread use of synthetic agrochemicals in crop protection has led to serious concerns of environmental contamination and increased resistance in plant-based pathogenic microbes. In an effort to develop bio-based and non-synthetic alternatives, nanobiotechnology researchers are looking to plants that possess natural antimicrobial properties. In new work, researchers show that nanoscale thymol's antibacterial and antifungal properties not only prevent plant disease but that it also enhances plant growth.

Metal-organic frameworks can enhance sonodynamic cancer therapy

Thu, 03 May 2018 16:50:52 -0400

Sonodynamic therapy (SDT) has attracted wide attention as a novel treatment strategy for deep-seated tumors due to its safety, tissue penetration depth and low cost. However, traditional organic sonosensitizers tend to suffer from low water solubility, fast metabolism and elimination from the blood circulation. Sciebtists now report the excellent potential of metal-organic-framework (MOF)-derived mesoporous carbon nanostructures containing porphyrin-like metal centers in SDT augmentation.

Piezoelectric nanotechnology platform inhibits breast cancer cell proliferation

Wed, 02 May 2018 07:37:20 -0400

Scientists report an innovative nanotechnological approach for inhibiting the proliferation of breast cancer cells. For the first time, a wireless treatment based on piezoelectric nanoparticles has been exploited to remotely deliver electric stimulations to breast cancer cells. The team shows that chronic electric stimulations mediated by piezoelectric nanoparticles result in the ability to significantly reduce the breast cancer cell proliferation by affecting the ion homeostasis and the organization of the mitotic spindles during cell division.

A nano squeegee to clean nano sheets

Tue, 01 May 2018 05:41:02 -0400

By precisely stacking various 2D materials in a predetermined sequence on top of each other, researchers create van der Waals heterostructures that, due to their unique interlayer coupling, have special optoelectronic properties. Unfortunately, the study of 2D monolayers is plagued by trapped contaminants in between the 2D sheets as well as between the 2D sheets and the underlying substrate. These contaminants make it difficult to obtain precise and reproducible experimental observations. A simple technique for removing these contaminants in a process similar to a squeegee.

Nanopatterning holograms onto commercial contact lenses

Mon, 30 Apr 2018 01:37:04 -0400

Researchers report a new a method to produce optical nanostructures on commercial contact lenses. This method aids in functionalizing and nanotexturing an of the shelf, commercial contact lens. This adds to the trend of the humble contact lens, widely used to correct common vision problems, being on its way to become a 'smart' diagnostic tool. Tears contain diagnostic information regarding ocular diseases, and they can be used as a surrogate medium for analyzing blood chemistry.

Energy-saving windows made from common glass and cheap nanocrystals

Fri, 27 Apr 2018 04:40:26 -0400

One of the main challenges for energy efficient technologies is to lower their cost by making cheap energy-efficient materials and devices by preferably using green manufacturing technologies. For example, commercial infrared-blocking windows, both passive and active, are simply too expensive (most of these IR-blocking windows contain an expensive silver coating) and they are not used in the majority of our homes. One approach to this problem involves creating passive infrared-blocking glasses using plasmonic nanocrystals. Researchers have demonstrated that nanocrystals of relatively inexpensive plasmonic materials show an overall good performance as IR-blocking elements.

Multiple electromagnetic responses from accordion-like plasmonic nanorods

Thu, 26 Apr 2018 06:47:44 -0400

Well-defined complex nanostructures for metamaterials with unique optical properties - such as negative refractive index, strong artificial optical activity and perfect absorption - are usually prepared by top-down approaches, including direct laser writing, multiple e-beam lithography, and membrane projection lithography. In a recent breakthrough, scientists have combined block copolymer self-assembly and an anodized aluminum oxide template to fabricate unique complex nanostructures over a large (centimeter) area.

How to eliminate a graphene oxide 'oil spill' accident

Wed, 25 Apr 2018 04:54:55 -0400

Carbon nanomaterials, including graphene-based materials, are widely gaining popularity in practical applications of nanomanufacturing. As a result, it becomes more and more likely that the unwanted introduction of such materials into the environment may occur. In particular, aqueous habitats might be severely affected by any accidental carbon nanomaterials exposure. Researching these potential environmental toxicity effects, scientists have found that kaolin, a cheap and abundant clay, can act as a powerful antidote to remediate the toxic effects of graphene oxide.

A second skin with switchable wettability

Tue, 24 Apr 2018 04:23:04 -0400

Creating smart superhydrophobic (i.e. extremely water-repellent) surfaces is of increasing importance in cutting-edge applications such as self-cleaning, anti freezing, anticorrosion, anti biofouling, water/oil separation, and microfluidics. Researchers now managed to demonstrate a skin-like superhydrophobic surface, which can be switched into different wetting properties by simple body motion. This active surface enables on-demand manipulation of water droplets without energy supply or external appliance.

Nanotechnology could give us battery-free electronic toys

Mon, 23 Apr 2018 03:01:15 -0400

A triboelectric nanogenerator (TENG) utilizes charges arising from friction similar to the static we experience on dry winter days; and by nanostructuring the materials in a TENG device, the produced energy could be amplified by increasing the contact area of the surfaces. In a step toward the commercialization of triboelectric nanogenerator (TENG) devices, researchers have presented a novel approach that uses TENG technology to develop battery-free, self-powered electronic toys.

An alternative to antibiotics - weakening superbugs' grip

Fri, 20 Apr 2018 02:50:37 -0400

The growing threat of antibiotic-resistant bacterial strains may pose grave risks for society: A post-antibiotic era means, in effect, an end to modern medicine as we know it. New research findings could point the way to new treatments for now-invincible bacterial foes, not by developing a new antibiotic that would kill these bacteria, but by making them weaker so that they get more easily attacked by our immune system. Understanding the physical mechanisms that underlie this persistent stickiness at the molecular level is instrumental to combat these invaders.

One-dimensional quantum materials can deliver record-high current densities

Thu, 19 Apr 2018 06:51:20 -0400

The advent of graphene resulted in a massive, world-wide, effort directed at investigation of other two-dimensional (2D) layered materials. One-dimensional (1D) bundled materials have received considerably less attention. Similar to the 2D layered materials with covalently bonded layers separated by the van der Waals gaps, the 1D materials consist of covalently bonded one-dimensional wires with van der Waals gaps between the wires. Researchers now have discovered that quasi-1D nanoribbons reveal an exceptionally high current density at the peak of the stressing DC current. This level of the current density exceeds that in any conventional metals like copper by almost two orders of magnitude.

Nanotechnology takes steps towards artificial retinas

Wed, 18 Apr 2018 03:19:41 -0400

Sensory substitution with flexible electronics is one of the intriguing fields of research that takes place in nanotechnology labs around the world. In line with this focus on human senses, in the future artificial retinas integrated with the human body may not only repair damaged vision but also expand it to see a wider range wavelengths (e.g. ultraviolet light). Researchers now have demonstrated a new self-powered brain-linked vision electronic skin (e-skin) for mimicking the human retina. The general idea of our device design of brain-linked vision electronic skin is constructing an integrated flexible system including photodetector array, information analyzer, signal transmitter, and electricity power unit.

Graphene-oxide-based membranes for large-scale energy storage systems

Tue, 17 Apr 2018 02:43:59 -0400

As a promising large-scale energy storage technology, redox flow batteries (RFBs) are attracting increasingly more research attention. For RFB separators, the essential requirement is achieving high ionic conductivity with minimal cross-over at low cost. Researchers now have demonstrated a proof-of-concept graphene oxide (GO) membrane as separator for large-scale energy RFBs. Their work shows that the two-dimensional nanochannel structure and low frictional water flow inside micrometer-thick GO laminates make this material an attractive candidate membrane for large-scale energy storage systems.

Driving nanomotors through road blocks inside living cells

Mon, 16 Apr 2018 05:03:13 -0400

Researchers demonstrate that helical shaped magnetic nanomotors can be maneuvered inside a living cell. This new and versatile technique has the potential ability to position any payload at any desired location inside a living cell itself, which is of great importance in the field of biology and biophysics. The helical shaped nanomotors are made of mainly silica and a thin layer of magnetic material, while their size is at least ten times smaller than the cell which they enter in. A rotating magnetic field is used to drive the motors inside the cytoplasm with precise control.

Nanosilicates grow bone and cartilage tissue from stem cells in the absence of growth factors

Fri, 13 Apr 2018 08:56:33 -0400

Researchers have demonstrated that a specific type of two-dimensional (2D) nanoparticles, nanosilicates, can grow bone and cartilage tissue from stem cells in the absence of growth factors. These nanoparticles are similar in shape to a coin, but 10 billion times smaller in size. Nanosilicates consist of minerals such as sodium, silicate, magnesium and lithium, which are already present in the body. This avoids the use of growth factors in the human body, which can generate harmful effects including unwanted tissue growth, such as a tumor.

Point-of-care biosensor for rapid and accurate sepsis diagnosis

Thu, 12 Apr 2018 08:08:49 -0400

Sepsis is the body's extreme response to an infection. It is life-threatening condition in which bacteria or fungi multiply in a patient's blood - often too fast for antibiotics to help. Without timely treatment, sepsis can rapidly cause tissue damage, organ failure, and death. A critical unmet need in combating sepsis is the lack of accurate early biomarkers that can alert clinicians to a potential life-threatening situation and allow them to take preventative action. In a new study, researchers report the development of a point-of-care platform for rapid sepsis detection, called IBS (integrated biosensor for sepsis).

Design of nanochannel interfaces is a key point in energy utilization

Tue, 10 Apr 2018 07:25:34 -0400

The ability of nanochannels to regulate transported substances in confined spaces is of great research interest in innovative applications, such as high-resolution sensing, filtering, and high-efficiency energy utilization. In the last area, research on nanochannels in energy-related areas continues to face challenges such as low efficiencies, complex preparation processes, and high fabrication costs. Overcoming these challenges is an important and difficult task in the field of energy conversion, energy conservation, and energy recovery.

Flexible data storage based on organic nanomaterials

Mon, 09 Apr 2018 04:36:49 -0400

Next-generation electronic devices will be highly portable, wearable - even transplantable - lightweight, and most likely self-powered. Among the various functional block required for these systems (such as displays, sensors, actuators, etc), some of the most important components are novel flexible data storage systems that possess nonvolatile ability, high-density storage, high-switching speed, and reliable endurance properties. Especially organic memories have been considered as the most promising candidates to be used in various portable and wearable systems in future due to their remarkable advantages of nonvolatile memory features, low cost, easy fabrication, and flexibility.

Batch-assembly of reconfigurable, multimodal 3D electronics (w/video)

Tue, 03 Apr 2018 01:00:23 -0400

Whiskers on animals allow them to build a rich understanding of their environment by feeling objects or even the flow of fluids. Many animals can also actively sweep, or 'whisk', their whiskers, enabling them to gather complex information about the architecture of their environment. Researchers have replicated this whisking action by exploiting the shape memory effect of a polymer substrate, which can be dynamically repositioned by modulating the temperature and air flow across the electronic whiskers (e-whiskers).

Single crystalline epitaxy of all inorganic lead-free halide perovskite paves the way for high-performance electronics

Thu, 29 Mar 2018 00:15:04 -0400

Halide perovskites have attracted tremendous interest due to their fascinating optoelectronic properties. Driven by the concerns of toxicity derived from lead and instability caused by organic components, researchers have turned to all-inorganic lead-free halide perovskites. However, compared to hybrid lead perovskite, lead-free compositions usually demonstrate poor crystallinity, low ordering, and high defects that suppress the performance of optoelectronic devices. Scientists now have deployed a new approach to grow all inorganic lead-free halide perovskites.

New technique accurately measures the water slippage in single graphene nanofluidic channels

Tue, 27 Mar 2018 21:24:24 -0400

For most viscous liquids, the solid surface of surrounding channel walls poses friction resistance to the flowing liquid, causing a loss of velocity at the liquid/solid interface. As a result, for regular surfaces the energy required for nanofluidic applications is enormous because of the tremendous hydraulic resistance inside nanoscale conduits. A new technique to accurately measure the hydraulic resistance inside graphene nanofluidic channels makes increasing the efficiencies of most nanofluidic applications possible.

Few-layer antimonene decorated microfiber improves optical modulation communication with enhanced long-term stability

Mon, 26 Mar 2018 20:08:27 -0400

Researchers have used a few-layer antimonene nanosheet to demonstrate all optical modulation in optical signal processing. To utilize the saturable absorption property of few-layer antimonene, antimonene-decorated microfiber was employed as an optical saturable absorber that can allow for passive mode-locking, Q-switching and all-optical thresholding at the telecommunication band. These results may provide guidance for the application of antimonene and other Group VA mono-elemental 2D materials in ultra-short pulse generation and all optical thresholding with enhanced long term stability.