Nanoscale sensors based on silicon nanowires and carbon nanotubes are capable of detecting molecules at ultra low concentrations. The potential applications include early detection of cancer and fast sequencing of genome. However, for these applications, the time taken by the sensor to reach stable response is crucial. This time is dictated by the diffusion of molecules (e.g. cancer markers) through the solution and their subsequent capture at the sensor surface. Researchers at Purdue University show that this response is governed by the geometry of diffusion of the system and that nanobiosensors are capable of detecting bio-molecules at much lower concentration than the classical planar sensors.
Researchers in South Korea used single-walled carbon nanotubes (SWNTs) to tag single-stranded DNA to locate a particular sequence of DNA within a complex genome. The results show that SWNTs may be used as generic nano-biomarkers for the precise detection of specific kinds of genes.
Addressing the potential hazards associated with nanomaterials requires a comprehensive approach to gaining, collecting and publishing knowledge about individual nanomaterials. Expanding MSDS (Material Safety Data Sheets) into nMSDS for nanomaterials could be a way to accomplish this.
A new method based on the nanoscale Kirkendall effect was demonstrated to fabricate compound nanotubes. Through a spinel-forming solid-state reaction, high aspect-ratio core-shell ZnO-Al2O3 nanowires transform into monocrystalline ZnAl2O4 nanotubes.
Researchers at the University of Illinois at Urbana-Champaign have shown that, by employing small pieces of DNA molecules called aptamers, nanomaterials can be smart enough to assemble or disassemble only in the presence of programmable signals such as AND or OR, with controllable cooperativity.
In order to survive, biological systems need to form patterns and organize themselves. Scientists at the Max Planck Institute for Colloids and Interfaces (MPI-KG) in Potsdam, Germany, have now combined self-organization with chemical pattern formation. They demonstrated that oscillating reaction patterns like that of a Belousov-Zhabotinsky reaction can not only be generated in a one-phase system like in all previous examples but also in a two-phase system like liquid-solid.
Superhydrophobic surfaces, such as lotus leaves, with micro/nano combined structures found in nature have attracted a lot of interest because of their importance in fundamental research and practical applications such as self cleaning, anti-fogging/snowing, drag reduction effect etc. In this regard, diverse methods have been proposed to produce such surfaces. However, most of the reported methods in the literature generally require a cleanroom-based process or complex chemical processes and have some limitations in terms of mass-production capability and material selectivity.
The color of metal colloids is highly dependent on their size and therefore being able to control the size is very important to tune the metal colors systematically. By controlling the wavelength of optical resonance of metal nanoparticles and their composition, researchers in South Korea have found a way to fabricate various colored metal colloids both easily and reproducibly. These findings could be very useful for biological assays.