Graphene's piezoresistive effect, combined with its other properties such as ultra-translucency, superior mechanical flexibility and stability, high restorability, and carrier mobility, enables the use of graphene in high-sensitivity strain sensors. Potential application areas for these sensors could be found in flexible display technology, robotics, smart clothing, electronic skin, in vitro diagnostics, implantable devices, and human physiological motion detection - which has been considered as an effective approach to evaluate human health. To demonstrate this application, researchers have now reported on a method to monitor human motions.
Nanowire field-effect sensors show significant advantages of real-time, label-free and highly sensitive detection of a wide range of analytes in liquid phase, including proteins, nucleic acids, small molecules, and viruses in single-element or multiplexed formats. Motivated by the unique features of these sensors and the ease to integrate them in the currently available VLSI technology, researchers used molecularly modified silicon nanowire FETs to detect volatile organic compounds (VOCs) that are associated with environmental pollution, quality control, explosive materials, or various diseases.
Recently, nanotechnology researchers have begun to work with graphene foams - three-dimensional structures of interconnected graphene sheets with extremely high conductivity. Since graphene foam possesses a high porosity of close to 100%, this offers the opportunity to use it as a scaffold for other nanomaterials to generate synergistic effects. Now, researchers have fabricated vertically aligned ZnO nanowire arrays on 3D graphene foam and used this electrode to detect uric acid in a reliable statistical level from the serum of Parkinson's disease patients.
Previous work in stretchable, flexible electronics has shown that conventional, silicon wafer based fabrication techniques can be modified to apply electronics conformally to the heterogeneous topography of the skin. Now, researchers have demonstrated the development of a device platform that enables high precision temperature mapping of the skin in ways that have, until now, been extremely difficult in research and impossible to implement for widespread use.
Functionalized graphene holds exceptional promise for biological and chemical sensors. In new work, researchers have shown that the distinctive 2D structure of graphene oxide, combined with its superpermeability to water molecules, leads to sensing devices with an unprecedented speed. The team reports the experimental observation of the unparalleled response speed of humidity sensors based on graphene oxide, which are - to the best of the scientists' knowledge - the fastest humidity sensors ever reported.
Different strategies for creation of self-healing coatings to prevent corrosion degradation have been suggested. The goal is to significantly reduce the maintenance costs in many industrial applications by applying active sensing coatings. Today we look at a novel sensing coating on the basis of nanocapsules containing pH-indicating agent. The main idea of this work is to create a novel active protective coating which is able to indicate when corrosion processes start under the coatings or in different defects.
Thanks to nanotechnology, medical research is moving quickly towards a future where intelligent medical implants can continuously monitor their condition inside the body and autonomously respond to changes such as infection by releasing anti-inflammatory agents. A recent review discusses present and prospective implantable sensors incorporating nanostructured carbon allotropes. The authors describe various applications with an in-depth look at the implantable sensors from the viewpoints of nanomedicine, materials science, nanobiotechnology, and sensor design, both present and future.
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.