Saturday, February 11, 2017
Eating Small Applications and Implications for Nanotechnology in Agriculture and the Food Industry
Eating Small Applications and Implications for Nanotechnology in Agriculture and the Food Industry
The following will be published next month in the journal Science Progress http://www.sciencereviews2000.co.uk/view/journal/science-progress, which I am an editor of - so, this is a preview!
1. Introduction.
That synthesis might be undertaken by the direct manipulation of atoms was suggested by Richard Feynman in 1959, although term "nano-technology"1 was not coined until 1974, by Norio Taniguchi. In 1986, K. Eric Drexler published his book Engines of Creation: The Coming Era of Nanotechnology, which contained the notion of a nanoscale "assembler" with the capacity to build copies of itself and other items, by atomic level manipulation. The groundbreaking invention, in 1981, of the scanning tunnelling microscope (STM) demonstrated that individual atoms could be visualised, and the technology was further developed to physically move adsorbed atoms and molecules around on a surface2. Notable examples2demonstrated for publicity purposes are the sign-writing of "IBM" using 35 xenon atoms on a Ni(110) surface, and of "2000" using 47 CO molecules on a Cu(211) surface, by researchers in the eponymous organisation, to auger in the new millennium. Considerably larger molecules can also be moved using an STM tip, for example 1,4-diiodobenzene and biphenyl, which have been towed around on copper surfaces. The tunnelling electrons may also be used to initiate chemical reactions, the products of which can be subsequently manipulated over the surface, so providing proof of chemical change having occurred, e.g. the conversion of iodobenzene to biphenyl. As a definition, nanotechnology (nanotech) can be described as the manipulation of matter over an atomic, molecular, and supramolecular dimension. Molecular nanotechnology is the intention of manipulating atoms and molecules, so to create macroscale products. The prefix “nano” is derived from the Greek word meaning “dwarf”. The U.S. National Nanotechnology Initiative3 defines nanotechnology as, “the manipulation of matter with at least one dimension in the range 1—100 nanometers (nm)”, where quantum mechanical effects become increasingly important as the smaller end of the range is accessed. It is critical that the particular materials, and devices made from them, should possess properties that are different from the bulk (micrometric or larger) materials, as a consequence of their small size, which may include enhanced mechanical strength, chemical reactivity, electrical conductivity, magnetism and optical effects (e.g. Figure 1).
One nm is one billionth, or 10?9, of a meter, which in relative size to a meter is about the same as that of a marble to the Earth.4 Placed in a different context, an average mans beard grows about one nm in the time it takes him to lift the razor to his face.4 The lower limit is set by the size of atoms, which are the fundamental building blocks of nanotechnology devices, while the upper limit is of a more arbitrary quality but is of the dimension at which the particular phenomena of the quantum realm begin to appear, which are essential to the nano-device. A device that is merely a miniaturised form of an equivalent macroscopic version does not conform to nanotechnology, lacking these particular phenomena, but is classified under the heading microtechnology.5 In regard to the fabrication of nanodevices, we find the "bottom-up" approach, where materials and devices are constructed from molecular components which self-assemble via molecular recognition, while in the "top-down" approach, nano-objects are built from larger entities, not involving control at an atomic level.6
The plural forms "nanotechnologies" and "nanoscale technologies" thus refer to the many and various aspects, devices and their applications that have in common this scale of the quantum realm. Indeed, there are multifarious potential applications of nanoscale materials, including industrial and military uses, as attested by the investment of $3.7 billion, by the U.S. National Nanotechnology Initiative, $1.2 billion by the European Union and $ 750 million in Japan.1 It may be that nanotechnology can provide advances in medicine, electronics, biomaterials, energy production and, as is the subject of this article, in agriculture and more broadly in the food industry. On the other hand, nanotechnology raises many of those same issues as when any new technology is inaugurated, e.g. concerns about the toxicity and environmental impact of nanomaterials,1and their potential effects on global economics, in addition to speculation over potential doomsday scenarios (“grey goo”), most emphatically dramatised by the late Michel Crighton in his novel Prey7. The Royal Societys report on nanotechnology contains examples of some of the definitions and potential implications of nanotechnologies.8 Commercial products, so far, are limited1 to bulk applications of nanomaterials, rather than atomic scale synthesis, e.g. the use of silver nanoparticles as a bactericide, nanoparticle-based transparent sunscreens, and stain-resistant textiles based on carbon nanotubes.The aspects embraced by nanotechnology are broad, and there is much work and concern over the large-scale employment of engineered nanoparticles (ENMs) and their effects on the environment, agriculture, and plants, and the humans who consume them directly. Moreover, as this short survey attempts to indicate, there is also now a considerable body of work in the applications of nanoscale technology to agriculture and the food industry. Indeed, an ACS Select was recently published on this topic9.Thus may be provided novel sensors intended to improve the quality and safety of food, along with methods of packaging that will amend the storage and delivery of foodstuffs.
According to the researchers and stakeholders, revolutionary advances can be anticipated during the next 10-15 years, principally through a convergence of nanotechnology, biotechnology and agricultural and environmental sciences, of which the following have been listed9:
•development of nanotechnology-based foods with lower calories and less fat, salt, and sugar while retaining flavour and texture;
•nanoscale vehicles for effective delivery of micronutrients and sensitive bioactives;
•re-engineering of crops, animals, and microbes at the genetic and cellular level;
•nanobiosensors for detection of pathogens, toxins, and bacteria in foods;
•identification systems for tracking animal and plant materials from origination to consumption;
•integrated systems for sensing, monitoring, and active response intervention for plant and animal production;
•smart field systems to detect, locate, report, and direct application of water;
•precision and controlled release of fertilizers and pesticides;
•development of plants that exhibit drought resistance and tolerance to salt and excess moisture; and
•nanoscale films for food packaging and contact materials that extend shelf life, retain quality, and reduce cooling requirements.
2. Nanotechnology in agriculture.
2.1 Precision Farming.
Precision farming aims to maximise output (i.e. crop yields) while minimising input (i.e. fertilisers, pesticides, herbicides, water etc). Computers, global satellite positioning systems, and remote sensing devices are all employed in the monitoring of highly localised environmental conditions, so to determine whether crops are growing at maximum efficiency or any specific problems, and their precise location. The input of fertilizers and water use can be optimised, resulting in lower production costs and potentially greater production. The amount of waste from agriculture can also be reduced, further minimising its environmental impact. Real-time monitoring may be achieved through linking nanotechnology-enabled sensor devices with a GPS system. By dispersing nanosensors throughout a field, soil conditions and crop growth could be continuously monitored. A wi-fi system has been introduced in one of the Californian vineyards, Pickberry, in Sonoma County , for which the initial cost is justified since it enables the best grapes to be grown, to produce finer wines, to be sold at a premium price10.
2.2 Smart Delivery Systems.
