Epigenetic mechanisms are chemical changes in DNA that do not alter the actual genetic code but can influence the expression of genes, and can be passed on when cells reproduce. One of the most important is DNA methylation, where methyl groups - small structures of carbon and hydrogen - are appended to specific locations on a DNA strand. Recently, both biological and synthetic nanopores have been proposed for DNA methylation detection. In new work, researchers employed protein nanopores to investigate a novel metal ion-bridged DNA interstrand lock, and explore its potential in location-specific methylation detection.
DNA is a powerful biomaterial for creating rationally designed and functionally enhanced nanostructures. Emerging DNA nanotechnology employs DNA as a programmable building material for self-assembled, nanoscale structures. Researchers have also shown that DNA nanotechnology can be integrated with traditional silicon processing. DNA nanoarchitectures positioned at substrate interfaces can offer unique advantages leading to improved surface properties relevant to biosensing (for instance, graphene and DNA can combine to create a stable and accurate biosensor), nanotechnology, materials science, and cell biology.
Recent developments in nanotechnology have enabled significant improvement in the field of anti-counterfeiting measures. One company for instance is working on fluorescent nanostructures to improve banknote security; another one has developed DNA tags for deposition on nanoelectronics wafers and computer chips to ensure the integrity and security of processed wafers. DNA-based protection technologies are especially suitable for anti-counterfeiting measures.The DNA molecules are added a products raw material during the production process. Only 1 ppm (one part per million) is required to uniquely mark the material The DNA molecular structure can then be read as a mathematical code based on the four DNA molecules. So a DNA code, in contrast to the binary code used in IT security, is a combination of the letters A, C, G and T. A 10-digit code could look like this: C-G-A-C-T-T-G-A-C-A.
The emission of light by a single molecule is a cornerstone of nano-optics that will enable applications in quantum information processing or single-molecule spectroscopy. However, a key challenge in nano-optics is to bring light to and collect light from nano-scale systems. In conventional electronics, the interconnect between locally stored and radiated signals, for example radio broadcasts or mobile phone transmissions, is formed by antennas. For an antenna to work at the wavelength of light it is necessary to downscale the structure by the same factor as the wavelength or the frequency of the wave, i.e. roughly by a factor of 10 million. Once the nanofabrication issues are sorted out, nano-optical antennas could become ubiquitous in all applications based on light-matter interactions such as sensing, light emission (e.g. LEDs) and detection, as well as light harvesting, i.e. for solar cell applications.
Vaccination is one of the most effective ways to prevent microbial infection. Synthetic vaccines can combine a portion of a microbe, known as an 'antigen' together with an adjuvant that stimulates the immune system. Delivering both the adjuvant and antigen to the appropriate immune cells is challenging. DNA nanotechnology may provide a solution by acting as a scaffold to co-deliver both antigen and adjuvant. However, the potential of DNA nanostructure-based vaccines has only been demonstrated in vitro. Now, a team of researchers based out of Arizona State University demonstrated that DNA nanostructures with appended adjuvants could elicit antibody production against a model antigen in mice.
Every aspect of cellular activities, including cell proliferation, differentiation, metabolism and apoptosis, can be regulated by a class of tiny but very important nucleic acids fragments called microRNAs (miRNAs). They bind to specific messenger RNAs and cause messenger RNA degradation or inhibit translation, thereby regulate gene expression at the post-translational level. In cancer cells, the homeostasis of these normal biological processes is disrupted, partially by dysregulated miRNAs, therefore the level of microRNAs is an indicator to the disease development, and miRNAs in cancer tissues or biofluids can be utilized as a diagnostic biomarker for cancer detection. Now, researchers report a miRNAs-based discovery that could provide a much earlier warning signal for lung cancer.
DNA origami is a design technique that is used by nanotechnology researchers to fold DNA strands into something resembling a programmable pegboard on which different nanocomponents can be attached. These DNA assemblies allow the bottom-up fabrication of complex nanostructures with arbitrary shapes and patterns on a 100 nm scale. For instance, DNA origami have been heralded as a potential breakthrough for the creation of nanoscale circuits and devices. DNA can also be metallized with different metals, resulting in conducting nanowires. Researchers have now have developed a method to assemble metallic nanocircuits with arbitrary shapes, by attaching metallic nanoparticles to select locations of the DNA origami and then fusing them to form wires, rings, or any other complex shape. These pre-designed structures are programmed by fully utilizing the self-assembling and recognition properties of DNA.
To build microprocessors with more than one billion transistors, manufacturers still use the same technique - photolithography, the high-tech, nanoscale version of printing technology - that they have been using for the past 50 years. State-of-the-art photolithography processes use 193 nm light to produce diffraction-limited features as small as 32 nm. Going beyond 32 nm, the cost and complexity rises significantly, posing massive technological and economic challenges for chip manufacturers. This provides plenty of incentives for researchers to explore alternative manufacturing technologies for chipmakers. One novel approach is based on the use of DNA nanostructures to pattern a silicon wafer.