Showing Spotlights 1073 - 1080 of 2204 in category All (newest first):
Several manufacturers are incorporating nano-sized particles of silver into, among other things, garments like socks and shirts to kill bacteria that cause odor. But does the silver stay in the socks or T-shirts? And what happens to it if it washes out? Also, what is the climate footprint of producing the required nanosilver? To answer these questions, a group of researchers have performed a cradle-to-grave life cycle assessment to compare nanosilver T-shirts with conventional T-shirts with and without biocidal treatment. For their assessment, the team used conventional T-shirts treated with triclosan, a commonly applied biocide to prevent textiles from emitting undesirable odors. The results show significant differences in environmental burdens between nanoparticle production technologies.
May 13th, 2011
Superparamagnetic iron oxide nanoparticles (SPIONs) are emerging as promising candidates for various biomedical applications such as enhanced resolution imaging or targeted drug or gene delivery due to their biocompatibility, low cost of production, ability to immobilize biological materials on their surfaces, and potential for direct targeting using external magnets. Over the past few years, researchers demonstrated that magnetofection is an appropriate tool for rapid and specific gene transfection with low dose in vitro and site-specific in vivo applications. In new work, scientists in Australia have now successfully demonstrated the use of magnetofection for the delivery of malaria DNA vaccine.
May 11th, 2011
Macrophages are white blood cells with a wide presence in various organs and tissues, that perform an essential role in keeping organisms healthy by scavenging cellular debris and disease agents. Since macrophages play an indispensable role in most pathological conditions, they represent an ideal target for therapeutic applications. Several approaches seeking to use macrophages for targeted therapies involve feeding therapeutic nanoparticles to macrophages ex vivo, followed by re-injection of the macrophages to target the diseased site. These techniques are often hampered by reduced drug release rates and drug degradation. Overcoming these limitations, scientists now report the ability of cellular backpacks to successfully encapsulate and controllably release drugs and avoid phagocytic internalization while remaining on the macrophage's surface.
May 10th, 2011
In the wake of the BP oil spill in the Gulf of Mexico we published a general overview of the wide variety of nanomaterials and nanotechnologies that offer significant promise for oil spill cleanup and recovery. One problem with many existing solutions though is that they are one-offs, i.e. one they absorb oil they can't be re-used and need to be disposed of (which could in turn create secondary pollution effects). Ideally, any oil absorbent material used during ocean oil spills should be reusable and with special wettability that could controllably capture and release oil pollution repeatedly. Addressing this issue, researchers have now created an underwater water/solid interface inspired by fish scales. The surface of this new material shows superamphiphobicity in air and superoleophilicity under water, allowing it to be repeatedly used to capture and collect oil droplets in water.
May 9th, 2011
The potential use of antimicrobial surface coatings ranges from medicine, where medical device infection is associated with significant healthcare costs, to the construction industry and the food packaging industry. Thin films containing silver nanoparticles have been seen as promising candidate coatings. Silver is known as one of the oldest antimicrobial agents. Silver ions are thought to inhibit bacterial enzymes and bind to DNA. Silver nanomaterials have been used effectively against different bacteria, fungi and viruses. Using something like an advanced form of a rubber stamp, scientists have now developed a way to adhere an ultra-thin (just a few molecules thick) antibacterial coating to a wound. The "stamped" area shows bactericidal activity for at least 48 hours.
May 5th, 2011
Damaged articular cartilages, like the ones found in the knee joint, ordinarily demonstrate a very limited capability for self-healing. Functional restoration of diseased or damaged articular cartilage is a major clinical challenge. There have been a number of successful approaches to tissue engineered cartilage, including the use of natural and synthetic biomaterial scaffolds. Although recent progress has been made in engineering cartilage of various shapes and sizes for cosmetic purposes, current treatments for cartilage repair are less than satisfactory, and rarely restore full function or return the tissue to its native state. Researchers have now developed nanofibrous hollow microspheres self-assembled from star-shaped biodegradable polymers as an injectable cell carrier. When the spheres are injected with cells into wounds, these spheres biodegrade, but the cells live on to form new tissue.
May 4th, 2011
Glues adhere to solid materials via a multitude of fundamental physical or chemical interactions. Either chemical reaction times or solvent evaporation rates determine the point in time, when this interaction sets in and fixes the object to be glued. Electric potential has been used to attract polymers continuously to an electrode surface and to toggle molecules between states for a molecular switch. If you wanted to create electric glue, you would need to be able to control the interaction of a polymer and an electrode surface reversibly, thus creating a nanoscale system with electrochemically controlled adhesion. A research team now describes how Coulomb forces between polymers and surfaces may be measured, controlled, and manipulated.
May 3rd, 2011
Heparin is widely used as an anti-coagulant to prevent the formation of blood clots. This naturally occurring biological molecule is commonly used during surgery for blood thinning. At the end of surgery, heparin has to be removed in order to allow the blood to clot again - this is currently done using a protein called protamine, the only clinically approved heparin binder. Unfortunately, protamine can cause severe allergic reactions in a number of patients. Researchers at the University of York have now developed a synthetic molecule which is capable of binding heparin just as effectively as protamine. The team's approach may eventually be useful for developing protamine replacements.
May 2nd, 2011