Nanotechnology Spotlight – Latest Articles

Showing Spotlights 2297 - 2304 of 3575 in category All (newest first):

The promise of nitric oxide-releasing nanoparticles as wound healing agent

Wound healing is an exceedingly complex process, involving a multitude of signaling pathways, effector molecules, response phases, as well as a moderated balance between all these components. Nitric oxide (NO) plays a critical role in the wound-healing process via antimicrobial properties, modulation of platelet/cytokine function, vasodilatory effects, and promotion of angiogenesis and matrix deposition. While attempts to administer NO to wound areas have shown some promise, the current modalities all suffer from varying drawbacks, such as administration site irritation or the burden of large, expensive equipment. Researchers have now introduced a nanoparticle platform comprised of silane based sol-gel and sugar-derived glasses that can generate, store, and deliver NO in a controlled and sustained manner is utilized to enhance wound healing in immunodeficient mice.

March 28, 2012

Move over chips - here come multifunctional labs on a single fiber

Optical fibers have revolutionized telecommunications by providing higher performance, more reliable telecommunication links with ever decreasing bandwidth cost. In parallel with these developments, fiber-optic sensor technology has been a major user of technologies associated with the optoelectronic and fiber optic communications industry. Today, with the rapid advance of communications and especially sensing applications, there is an ever increasing need for advanced performance and additional functionalities. This, however, is difficult to achieve without addressing fundamental fabrication issues related to the integration onto optical fibers of advanced functional materials at the micro- and nanoscale. Solving these technical problems will open up the possibility of developing multifunctional labs integrated onto a single optical fiber, exchanging information and combining sensorial data. This could result in auto diagnostic features as well as new photonic and electro-optic functionalities useful in many strategic sectors such as optical processing, environment, life science, safety and security.

March 27, 2012

Direct observation of how nanoparticles interact with the nucleus of a cancer cell

Nanotechnology offers new strategies to enable minimally invasive and localized approaches for diagnosing and treating cancer, thereby avoiding the serious side effects and shortcomings of chemotherapy. For instance, it has been shown that often less than 1% of the administered drug molecules during chemotherapy enter tumor cells and bind to the nuclear DNA. Another complication is drug resistance of cancer cells. This actually is one of the main causes of failure in the treatment of cancer. Cancer researchers are looking to nanoparticles as a drug carrier capable of localizing and directly releasing drugs into the cell nucleus, leading to a high therapeutic efficacy. Although increased therapeutic efficacy has been realized, there have been no reports on visualizing at nanoscale dimensions how nanoparticles interact with specific organelles. In a new breakthrough for nanomedicine cancer research, scientists have now reported the direct visualization of interactions between drug-loaded nanoparticles and the nucleus of a cancer cell.

March 26, 2012

Compelling evidence for silicene - the silicon analogue to graphene

The fascination with two-dimensional (2D) materials that has started with graphene has spurred researchers to look for other 2D structures like for instance metal carbides and nitrides. One particularly interesting analogue to graphene would be 2D silicon - silicene - because it could be synthesized and processed using mature semiconductor techniques, and more easily integrated into existing electronics than graphene is currently. However, silicene does not seem to exist in nature nor is there any solid phase of silicon similar to graphite. Nevertheless, silicene has been predicted by theory as early as 1994. Researchers have now presented the first clear evidence for the synthesis and thus the existence of silicene - a two-dimensional material, with a honeycomb-like arrangement of silicon atoms.

March 23, 2012

Dynamically controlling graphene's properties with engineered piezoelectricity

One of the greatest challenges in harnessing the power of nanotechnology is achieving dynamic control of mechanical, electronic, optical and chemical properties of nanoscale structures and devices. Dynamic control can be achieved through the use of piezoelectric materials. These are materials where applying a mechanical strain results in an electrical voltage or conversely, application of an electric field induces mechanical deformation. While piezoelectricity has mainly been shown for 3D bulk materials, the piezoelectric effect has also been demonstrated and exploited at the nanoscale. Researchers have now demonstrated through density functional theory calculations that piezoelectricity can be engineered into non-piezoelectric graphene by selective surface adsorption of atoms on only one side, which breaks inversion symmetry.

March 22, 2012

Ultrasensitive chemical nanocoax sensor based on carbon nanotubes

Various types of nanostructures are used in the development of nanosensors: nanoparticles, nanotubes, nanorods, two-dimensional materials like graphene, embedded nanostructures, porous silicon, and self-assembled materials. For instance, gas sensors often operate by detecting the subtle changes that deposited gas molecules make in the way electricity moves through a surface layer. Researchers have fabricated gas sensors based on carbon nanotube-based field effect transistors, which can detect electrical potential changes around them. While these and related sensing schemes can be all-electronic - i.e., not requiring optical readout - they all require sophisticated nanolithographic techniques to isolate, identify, and integrate electrical contact to the active nanosensor. Researchers have now presented a nanoscale 3D architecture that can afford highly sensitive, room temperature, rapid response, and all-electronic chemical detection.

March 21, 2012

Explosibility of nanoparticles

Recent studies have found that nanomaterials - in this case dusts and powders having nanosize particles - exhibit an explosion severity which is not disproportionate to micrometer-sized materials, but the likelihood of explosion is quite high due to very low ignition energies and temperatures. A recent review concludes that nanomaterials present a dust explosion hazard, with metallic nanoparticles being particularly reactive. Nanomaterials have been shown to display lower ignition energy and temperature requirements than larger particles. Due to this high sensitivity, explosion hazards may exist for many processes including, but not limited to, mixing, grinding, drilling, sanding, and cleaning.

March 20, 2012

A precise nanothermometer for intracellular temperature mapping

Green Fluorescent Protein (GFP) - originally found in a jellyfish - has played a crucial role in life science research, providing insights to many fundamental questions that have paved the way to the biology and medicine of the future. Since the mid-1990s, when the protein was successfully cloned, GFP can be found in research laboratories worldwide used as a visual marker of gene expression and protein localization, easily observed via light (optical) microscopy. GFP can be linked to other proteins and is primarily used to track dynamic changes in living cells. In 2008, biologists who discovered and developed the protein as a laboratory tool won a Nobel Prize for their work. Researchers in Spain have now demonstrated how GFP can also act as an efficient nano-thermometer inside cells.

March 19, 2012