Surface Enhanced Raman Spectroscopy (SERS) is a powerful analytical method that can detect trace amounts of substances, such as narcotics, toxins, and explosives. The detection is based on the fact that molecules of different substances interacting with light from a laser will scatter the light differently, providing a unique spectrum that can be used to identify the substance, much like a fingerprint. Researchers have used a microfluidic device to orchestrate the interactions between silver nanoparticles and methamphetamine molecules in saliva. The microfluidic device allows for the controlled introduction of the sample and the nanoparticles, and the subsequent aggregation of the nanoparticles into hot-spot rich clusters that allow us to detect minute amounts of the drug.
Understanding the purpose of the molecular modifiers that annotate DNA strands - called epigenetic markers - and how they change over time will be crucial in understanding biological processes ranging from embryo development to aging and disease. But just how the markers work, and what different markers mean, is painstaking work that still has left a long way to go. Advancing this research field, scientists have now reported the first direct visualization of individual epigenetic modifications in the genome. This is a technical and conceptual breakthrough as it allows not only to quantify the amount of modified bases but also to pin point and map their position in the genome.
When nanoparticles enter the human body, for instance as part of a nanomedicine application, they come into immediate contact with a collection of biomolecules, such as proteins, that are characteristic of that environment, e.g. blood. A protein may become associated with the nanomaterial surface during a protein-nanomaterial interaction, in a process called adsorption. The layers of proteins adsorbed to the surface of a nanomaterial at any given time is known as the protein corona. The type and amount of proteins in the corona composition is strongly dependent on several factors, including physicochemical properties of nanoparticles; protein source; and protein concentration - and temperature.
Direct visualization and manipulation of individual carbon nanotubes (CNTs) in ambient conditions is of great significance for their characterizations and applications. However, the direct visualization, location, and manipulation of individual CNTs is extremely difficult due to their nanoscale diameters. The observation of individual CNTs usually requires electron microscopes under high vacuum. Researchers now have proposed a facile way to realize optical visualization of individual carbon nanotubes and, based on that, macroscale manipulation of individual carbon nanotubes that could be carried out under an optical microscope.
Electronics will undergo revolutionary changes as the relatively novel disciplines of spintronics, nanoelectronics, and quantum computing come of age. A fundamental link between these fields can be established using molecular magnetic materials and, in particular, single-molecule magnets. Researchers have now demonstrated how to noninvasively graft a single-molecule magnet onto a carbon nanotube nanoelectromechanical system and probe the molecular nanomagnet with the carbon nanotube's mechanical motion.
The study of individual cells is of great importance in biomedicine. Many biological processes incur inside cells and these processes can differ from cell to cell. The development of micro- and nanoscale tools smaller than cells will help in understanding the cellular machinery at the single cell level. All kinds of mechanical, biochemical, electrochemical and thermal processes could be studied using these devices. Researchers have now demonstrated a nanomechanical chip that can be internalized to detect intracellular pressure changes within living cells, enabling an interrogation method based on confocal laser scanning microscopy.
Liquid-solid phase transitions can be an attractive route for the temperature regulation of electrical and/or thermal properties because of the availability of materials with a wide range of phase transition temperatures. Achieving different magnitudes of enhancement in solid and liquid state is difficult to explain from a theoretical point of view. When researchers made similar experiments using single-walled carbon nanotubes as the additives, they noticed much higher thermal conductivity improvement than the evidence available in existing literature. This is something they never anticipated to happen and they were quite surprised with the enhancement seen.
Researchers in Korea have found that rice husks - the outer, protective covering of a rice kernel - can be a source of silicon that can be used for high-capacity lithium battery anodes. Most of today's lithium-ion batteries rely on anodes made from graphite, a form of carbon. There are several candidate electrodes to replace graphite as the anode for lithium-ion batteries and silicon has been recognized as a favorable anode material because its capacity is 3-5 times larger than those of existing graphite anodes. The new work demonstrates that rice husks can be used to produce silicon with an ideal porous nanostructure for use in high-capacity lithium-ion battery anodes.