In a seminal paper more than 20 years ago, scientists described a device that was capable of causing drops of water placed on it to move uphill. However, as it turned out in subsequent research, drops of water are notoriously difficult to move from where they lie, unless they are large enough to be moved by gravity. In the absence of a microtube or of a channel - as they are required by most microfluidic devices - it usually is not possible to apply the pressure needed to induce liquid movement. An alternative approach, developed by researchers in Italy, is to pattern a gradient on a surface which allows a droplet to move in order to minimize its free energy.
While researchers are working on developing more cost-effective nanolithographic tools such as for instance superlens lithography, one of the key problems with nanofabrication is how to generate ever-challenging patterns with high resolution - especially for 3D nanostructures - and at the same time substantially reduce the cost of the process. A novel nanolithography method is based on light scattering from nanoparticles, which can generate 3D hollow-core structures that resembles 'nano-volcanoes'. Different from traditional lithography methods that are typically based on complex systems, this process relies solely on the light interaction with a single nanoparticle. No masks and external optics are needed in this approach, and light is manipulated into the desired optical pattern solely by the colloids.
Despite significant advances in the medical/surgical management of severe thermal injury, wound infection and subsequent sepsis persist as frequent causes of morbidity and mortality for burn victims not only due to the extensive compromise of the protective barrier against microbial invasion, but also as a result of growing pathogen resistance to our therapeutic options. Researchers have now demonstrated that encapsulating Amphotericin B, a intravenously administered potent fungicidal polyene macrolide, in nanoparticles increased its killing impact against numerous candida species, was more effective at preventing candidal biofilm formation, and cleared a mouse burn model infected with candida more effectively than solubilized amphotericin.
In terms of weight and size, batteries have become one of the limiting factors in the continuous process of developing smaller and higher performance electronic devices. To meet the demand for batteries having higher energy density and improved cycle characteristics, researchers have been making tremendous efforts to develop new electrode materials or design new structures of electrode materials. Researchers have now investigated the atomistic nature of the lithiation mechanism in individual tin dioxide nanowires by in situ transmission electron microscope and complementary density functional theory simulation.
While nanoparticles are emerging as drug carriers for targeted nanomedicines, preclinical assays to test nanoparticle efficacy are hampered by the lack of methods to quantitatively determine internalized particles. A novel method is suited to pave the way for preclinical testing of nanoparticles to establish dose-efficacy relationships and to optimize biophysical and biochemical parameters in order to make better drug delivery vehicles. The team demonstrated that it is possible to determine the exact number of nanoparticles inside a cell through a combination of three methods and a mathematical model which they developed to link the data from these three methods.
Under an applied magnetic field, iron oxide nanoparticles trigger cancer cell death by bursting intracellular organelles. These findings offer a new strategy to treat cancer using nanomaterials. Researchers may be able to administer magnetic nanoparticles externally, allow them to accumulate at the tumor site, and then irradiate them with a magnetic field to induce cancer cell death. In the past, antibodies and small molecules were used to trigger apoptosis in cancer cells. However, cancer cells often adapt to resist these treatments. Because iron oxide nanoparticles cause physical damage to cancer cells, it is difficult for them to develop resistance.
Fractals are structures built up from repeated sizings of a simple shape to make a complex one. A fractal is a geometric structure that can repeat itself towards infinity. Zooming in on a fragment of it, the original structure becomes visible again. In biological systems, fractal structures can be found everywhere - bronchial trees, vasculature, and nerve cells. These amazing structures can provide a specific interfacial contact mode that is highly efficient for absorbing sunlight, transporting nutrition, exchanging oxygen and carbon dioxide, and signal transduction. Researchers have now demonstrated the fabrication of programmable fractal gold nanostructured interfaces and their outstanding specific recognition of rare cancer cells from whole blood samples along with their effective release capability.
One major challenge in contemporary science is to accomplish with synthetic building blocks what nature does so well, that is, creating complex and functional structures through multiple levels of assembly of biomolecules. Bottom-up engineering of nanostructures that assemble themselves from polymer molecules are bound to become useful tools in chemistry. To that end, researchers are using block copolymer based micellar architectures to form hierarchical superstructures with defined shape and geometry. Researchers have now demonstrate that nanoparticles tethered with block copolymers resemble micelles that can assemble into well-ordered higher level mesostructures.