Conventionally, the fabrication of thin film nanostructures is primarily done by using selective etching or templating growth on a prepatterned resist and then performing lift-off. The solvents used in developing resist are typically toxic and add to the cost of lithographic processing. Recently, many environmentally friendly lithographic processes have been designed using either a water-based solution or supercritical carbon dioxide to develop the resist. A novel pure water developable spin-coatable lanthanum strontium manganese oxide (LSMO) resist has been developed by scientists in Taiwan. The use of pure water instead of organic or alkaline solvents would undoubtedly be not only environmentally desirable but also could greatly simplify the imaging process.
Current production methods for carbon nanotubes result in units with different diameter, length, chirality and electronic properties, all packed together in bundles, and often blended with some amount of amorphous carbon. The separation of nanotubes according to desired properties remains a technical challenge. Especially single-walled carbon nanotube (SWCNT) sorting is a challenge because the composition and chemical properties of SWCNTs of different types are very similar, making conventional separation techniques inefficient.
A number of neurodegenerative disorders, such as Parkinson's or Alzheimer Disease, may potentially be treated by gene therapy, i.e. the delivery of therapeutic genes to neurons. Currently, the most common carrier molecules to deliver the therapeutic gene to the patient's target cells are viruses that have been genetically altered to carry normal human DNA. Overall gene delivery efficiency is typically low for nonviral vectors. New research undertaken at The Johns Hopkins University offers a systematic approach to understanding the gene delivery process in neurons and explores the intracellular barriers to nonviral gene delivery and possible ways to improve their effectiveness.
Researchers have developed a highly sensitive, optical bio-molecule sensor that can distinguish between bio-molecules based on the variation to the light intensity of light due to the change in the path of coupled input light. The variation to the coupled light intensity and path is dependant on the nature of the bio-molecule and the density of the bio-molecules.
Individual quantum dots (QDs) have been widely investigated for the past 15 years, showing their potential applications in quantum computing. However, individual QDs are not enough for practical applications, but preparing and characterizing groups of QDs with controllable crosstalk (quantum dot molecule) is very challenging still. University of Arkansas researchers discovered a simply way to fabricate QD pairs, the most simple QD molecule. This provides a unique opportunity to study carrier interaction among QDs, one step further towards quantum computing.
Encapsulating metal nanoparticles inside carbon shells is of considerable significance but fraught with high manufacturing cost due to high energy consumption and intensive use of hardware. This cost issue limits their practical applications. Researchers in China have developed a novel, simple, efficient, and economical synthesis technique for the fabrication of carbon-encapsulated nanostructures where the carbonization is conducted at a relatively low temperature of 160C in water and no toxic reagents are added. This new technique is facile and versatile, and suitable for the coating of other transition metal with carbon.
A new study by Swedish researchers shows that gold nano spheres with a diameter of 7 nm, produced in a conventional laboratory surrounding, activate human antigen presenting dendritic cells (DCs) to induce proliferation of peripheral blood mononuclear cells (PBMC), mixed with either allergenic or autologous DCs. This effect was found to be due to endotoxin (lipopolysaccharide, LPS) contamination of the nanoparticles. When particles were produced in a controlled way eliminating endotoxin contamination, the activation of the DCs did not take place.
With the recent development in nanoscience and nanotechnology, a large variety of single-component nanomaterials (such as carbon nanotubes, nanoparticles, and quantum dots) and devices have been reported. There is now a pressing need to integrate multicomponent nanoscale entities into multifunctional systems and to connect these nano-systems to the micro/macro-world. This connection from the nano world to the macro world has been one of the long-standing problems in nanotechnology and still remains a big challenge. A novel approach of growing aligned carbon nanotubes (CNTs) around microsized carbon fibers should provide a useful platform technology for the development of various multidimensional and multifunctional nanomaterials and devices.