Latest advances in the field of nanotechnology like tiny porphyrin tubes to make a broad range of nanodevices, and tiny bioelectronic circuits to make nanotech machines or sensors, could lead to new useful devices. Healthcare Digital has explored this field further to tell you more…
Nanotechnology, often referred as “nanotech”, is the study of the controlling of matter on an atomic and molecular scale. Usually, nanotechnology deals with structures sized between 1 to 100 nanometer in at least one dimension. It involves developing materials or devices within that size.
Nanotechnology is a varied field – one that ranges from extensions of conventional device physics to new methods that are dependent on molecular self-assembly, from developing new materials with dimensions on the nanoscale to investigating whether we can directly control matter on the atomic scale.
Developments in nanotechnology, such as tiny porphyrin tubes to make a broad range of nanodevices, and tiny bioelectronic circuits to make nanotech machines or sensors, could lead to the invention of new devices.
Tiny porphyrin tubes have been made at Sandia. These may be used to make a series of nanodevices – including ones that could harness sunlight in order to split water molecules and produce hydrogen.
Sandia researcher John Shelnutt came up with the idea of employing sunlight to split water at the nanoscale. He developed the idea of hollow porphyrin nanotubes, which are micrometers long and 50-70nm in diameter, with about 20nm-thick walls. Porphyrin nanotubes are made of oppositely charged porphyrin molecules. These can assemble themselves in water at room temperature. Contrasting this, carbon nanotubes are developed at high temperatures, and they have covalent bonds between carbon atoms. Porphyrin nanotubes do not possess the mechanical strength of carbon nanotubes. However, they do have a wider range of optical and electronic properties. Porphyrin molecules are strongly connected to chlorophyll which are an active part of photosynthetic proteins. Currently, carbon nanotubes frequently are modified by attaching porphyrins to increase their uses.
The porphyrin nanotubes have intense resonance light scattering and photocatalytic activities. When exposed to light, some porphyrin nanotubes can grow metal structures – this could create a useful nanodevice. For example, if the nanotubes are put into a solution with gold or platinum ions and exposed to sunlight, their photocatalytic activity can cause the reduction of the ions to the metal. Scientists at Sandia have been successful in depositing platinum outside the nanotube to grow a nanowire of gold inside the tube. This is the main aspect of a new nanodevice that could allow the spliting of water into oxygen and hydrogen.
But water-splitting is only one of the possible applications of the nanodevices based on porphyrin nanostructures. Shelnutt said the tubes could be used as conductors, semiconductors and photoconductors, as well as electronic and photonic devices and chemical sensors. Scientists at the University of Wisconsin are conducting a research that could lead to new nanotech machines – or a new category of more sensitive biological attack sensors. They have used single cells of bacteria to make tiny bioelectronic circuits that could potentially be used in such devices. They directed the bacteria down a narrow channel to a pair of electrodes, where the bacteria were trapped by mild electric currents, thus making them “bio junctions”. These can be captured, interrogated and released at any point in time. Researchers say using living bacteria could become the foundation for fresh methods to accumulate all kinds of nanodevices.
According to Robert Hamers, professor of chemistry at the University of Wisconsin “One of the great challenges of nanotechnology remains the assembly of nanoscale objects into more complex systems. We think that bacteria and other small biological systems can be used as templates for fabricating even more complex systems.” He further added that it may be possible to take advantage of the complex topography of the surface of a bacteria cell and on the cell’s interactions with antibodies for researchers to construct much more complex nanoscale structures employing the innate ability of cells to dock or hold on to different kinds of molecules. Hamers said, “That would alleviate the painstaking manipulation of individual nanosized components such as microscopic wires and tubes”
He added, “We spend a lot of time making tiny nanowires, and then we try to direct them in place, but it’s very hard. But bacteria and other biological systems can be thought of as nature’s nanowires that can be grown easily and manipulated.”
Nanotechnology, as a field, has the potential to revolutionise healthcare for generations to come. The three main areas through which this can be achieved are diagnosis (especially while treating cancer), prevention and treatment. In future, nanotechnology can identify and stop potential sources of diseases in the body before they attack. This can be achieved through effective monitoring of individuals’ health (allowing diseases to be caught at their earliest stage) and germ-free hospital (limiting the opportunity for bacteria, viruses and other microbes to cause secondary diseases). Understanding the genetic make-up of the patient will allow physicians to prescribe personalised medicines in future using nanotechnology. Thus, advances, new research, discoveries and inventions in the field of nanotechnology are vital for the healthcare industry.