Some of the recent and significant developments in the area of nanotechnology applications for food quality control are discussed in this article. In food quality testing methods/devices, nanomaterials have various advantages over conventional materials such as ultra-sensitivity, selectivity, multiple targeting, portability, reproducible data processing, implantable conformability, on-board intelligence, non-invasive testing of packaged items, etc. Analytical chemistry plays a prominent role in food quality control and has already started taking advantages from the versatility and novel merits of nanoscience.
Most nanomotors designs are powered by quantum or, in most cases, catalytic chemical processes, the nanoscale equivalent of conventional internal heat engines that are so prevalent in our daily life has been missing. Researchers have now suggested a new type of ultrathin graphene engine which mimics an internal combustion engine system. This graphene engine consists of only a few parts - functionalized graphene, laser light, and substrate, which would make it simple to work with.
The nanotechnology-enabled detection of a change in individual cells, for instance cell surface charge, presents a new alternative and complementary method for disease detection and diagnosis. Since diseased cells, such as cancer cells, frequently carry information that distinguishes them from normal cells, accurate probing of these cells is critical for early detection of a disease. For this purpose, researchers have now designed a graphene-based optical refractive index sensor.
Studies have shown that in a favorable nano environment, enzyme immobilization onto nanosupports could lead to increased enzyme stability and improved specificity, and could allow for prolonged enzyme functionality through chemical and physical treatment. Researchers also have shown that immobilization onto carbon-based nanosupports can increase the enzyme turnover and allow for prolonged enzyme-based conjugates isolation and usage. In new work, researchers have now taken another step towards the detailed characterization and optimization of enzyme-nanosupport interface reactions.
Much hope (and hype) rides on graphene as a 'post-silicon' material for fabricating next-generation nanoelectronic devices. However, graphene's Achilles heel is its lack of an energy band gap. Therefore, graphene must be modified to produce a band gap, if it is to be used in electronic devices. Using a new approach, researchers now have demonstrated the operation of an all two-dimensional transistor, using a transition metal dichalcogenides channel material, hexagonal boron nitride gate dielectric, and graphene source/drain and gate contacts.
The growing market of power electronics creates new challenges for engineers and material specialists as it requires devices withstanding increasingly high voltages and for this new approaches to design and the adoption of new materials such as gallium nitride (GaN) and silicon carbide (SiC) are needed. The biggest point of attention for power electronics is breakdown voltage, that is, the highest voltage applicable to the device before it breaks down and starts to become non-functional.
The way graphene sheets are produced in solution, by exfoliation, is an original process, still not completely understood. The exfoliation of a 2D object from a 3D bulk material is a process spanning from the nano- to meso-scale due to bubble cavitation, intercalation and disruptive fragmentation. When characterizing these 2D sheet solutions, their average size and size standard deviation are commonly reported, often assuming that their size follows a 'normal' distribution. Experimental data shows that this is not the case.
For years, scientists and engineers have worked to design electronics which can interface with the body. However, typical silicon wafer-based electronics, which are planar and stiff, are not suited to interface with the soft, curvilinear, and dynamic environment that biology presents. By exploiting the features of shape-memory polymer (SMP) substrates, an international team of researchers has now demonstrated a unique form of adaptive electronics which softly conform or deploy into 3D shapes after exposure to a stimulus. The resulting organic thin-film transistors (OTFTs) can change their mechanical properties from rigid and planar, to soft and compliant, in order to enable soft and conformal wrapping around 3D objects, including biological tissue.