Graphene
Nanoplatelets
Graphene nanoplatelets with a normal thickness of the
5 – 10 nanometers are offered in differing sizes up to 50 microns.
Metal
Powders
Metal powder is a metal that has been broken
down into a powder form.
Metals that can be found in powder form include
aluminium powder, nickel powder, iron powder
and many more
FEATURED CATEGORIES
FEATURED PRODUCTS
Magnesium Oxide (MgO) Nanopowder/Nanoparticles Water Dispersion, Size: 45 nm, 22 wt%
Iron (II,III) Oxide (Fe3O4) Nanopowder/Nanoparticles Water Dispersion, Size: 13-18 nm, 22 wt%
Gold (Au) Nanopowder/Nanoparticles Dispersion, Purity: 99.99%, Size: 14 nm, 1200 ppm
Copper Oxide (CuO) Nanopowder/Nanoparticles Water Dispersion, Size: 20-50 nm, 22 wt%
Cerium Oxide (CeO2) Nanopowder/Nanoparticles Water Dispersion, Size: 25-45 nm, 42 wt%
Cerium Oxide (CeO2) Nanopowder/Nanoparticles Water Dispersion, Size: 25-45 nm, 22 wt%
Polymer Dispersant for Dispersion of Carbon Nanotubes (CNTs) in Ester Solvents
Multi Walled Carbon Nanotubes Water Dispersion, 4 wt%, Purity: > 96%, OD: 45-75 nm, Length: 8-18 µm
OUR LATEST NEWS
CARBON NANOFİBERS
Carbon Nanofibers
Carbon nanofibers (CNF) are noncontinuous, sp2-based linear filaments. In this article, a review is provided on carbon nanofiber’s growth, properties, and practical applications. CNFs can be synthesized majorly via catalytic chemical vapor deposition (CVD). Carbon nanofibers show flexibility, super strength, and high specific area because of their nanosized diameter, which enables them to be applied in energy storage devices’ electrode materials, bone tissue scaffold, filler in carbon-fiber-reinforced plastics, and so many other applications. Due to CNFs remarkable physicochemical properties, low cost, and small dimensions, CNFs are beneficial in useful applications extending from multifunctional composites, additives, or anode electrodes for batteries of lithium-ion, and for metal particles the materials that are supporting. CNFs are used in scanning probe microscopy (SPM), in field electron emission sources, in implafection, and so much more. As we mentioned, CNFs are suitable and appropriate for different applications in various areas.
Introduction
After metal, the most famous material is Carbon. They adhere to each other by forming a group, and by doing that, a really light and strong composite material is composed of fibers. Various stable molecules can be formed due to the high level of Carbon’s chemical bonding flexibility. All allotropes of Carbon have elemental Carbon but very different properties. CNFs are famous for their enhancements in electrical, thermal, mechanical properties, and electromagnetic shielding.Carbon is cheap, which makes it famous additive to materials of composites.They are really small. Techniques likeAtomic Force Microscopy and Scanning tunneling Microscopy are needed for examining CNFs properties. CNFs are nanostructures in a cylindrical shape with layers of graphene organized as cups, plates, or stacked cones.
In 1879, Thomas used bamboo and cotton as a light bulb’s filament, carbonized them to prepare Carbon fiber, since then, they have been upgraded and developed remarkably. Carbon nanofibers are implemented in various fields as a promising material, for instance, storage of energy and its conversion, devices that are self-sensing, and composites reinforcement. Linear filaments that are based on sp2 bonds are CNFs with 100 nm diameter and are described by aspect ratio (100) and their flexibility. Fiber Materials are of great importance, both scientifically and practically. CNF can be used for aerospace and vehicles in fabricating tough composites because of CNF’s flexibility, high mechanical strength, and high specific area. Except for the diameter, the CNF structure is very different from traditional carbon fibers.
CNF is very appropriate and capable of making advanced capacitors, and packaging semiconductor applications due to CNFs excellent characteristics joined with the remarkably low-temperature deterministic process of growth. Effective surface area is highly enhanced when CNFs are grown on the surface of metals because of their metallic nature. They consist of truncated conical, planar layers, and regularly stacked along the length of the filament. They are beneficial in reinforcing fillers in composites of polymer, in photochemical cells as photocurrent generators, catalyst’s supporting materials, and in plastics that are reinforced by carbon-fiber as hybrid-type fillers, all because of their remarkable structure which is chemically active and has the behavior of a semiconductor. CNF also functions as a material of the electrode. They have also uses in biomedical applications.
Synthesis
A well-known method is electrospinning polyacrylonitrile (PAN) followed by stabilization, and then carbonization, this is the convenient method to make continuous carbon nanofibers which exhibits noticeably different and remarkable properties that make them applicable for different applications.
CNFs of high purity in bulk production capacities were achieved at cheap cost via the process of chemical vapor deposition.With variants like plasma-assisted and thermal, the dominant technique commercially is CCVD or simply CVD. At high temperature, decomposition of gas molecules occurs, and deposition of Carbon occurs on a substrate in transition metal catalyst’s presence. The process of CVD falls into two categories, 1) floating-catalyst process (continuous), and 2) fixed-catalyst process (batch)
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Properties
Carbon nanofibers are fibrous, long layers of Carbon of a platelet type and single layers aligned perpendicularly and nested at an angle inside one another. The used catalyst determines the arrangement. The class of CNF’s is 1-D carbonaceous materials. CNFs are excellent in the storage of both lithium and sodium. For electrodes of non-carbon, CNFs act as porous substrates and electron-conducting, thus improving their ionic and electronic conductivity stabilizing the structure of electrodes during cycling, resulting in enhancement of the electrochemical performance of non-carbon cathode and anode materials. An individual CNF can grow as long as few microns, arranged vertically at a specific position standing alone. By implementing the low electric field on such CNFs, they can be easily bent, but after switching off the field, even the 900 bends can come back to the original position.
CNFs have a surface of the rough structure, with many edges and corners, which makes CNF a perfect material for processes of fast desorption/adsorption. If intermediate layers of metal are applied in between the layers of graphene, then an enhancement is shown by the material in CNF’s binding to matrices of metallic and ceramic. For designing the appropriate mechanical properties, other materials are joined with these fibers. In order to gain carbon fibers’ high performance, controlling the nanostructure and microstructure by choosing suitable organic precursors and appropriate conditions of processing is very important. Various remarkable possibilities arise in CNFs use in catalytic processes because of the catalytic activity combination with their remarkable thermal and electrical conductivity.
Applications
CNFs are used in scanning probe microscopy (SPM), in field electron emission sources, in implafection, and so much more. As we mentioned, CNFs are suitable and appropriate for different applications in various areas.
For Drug Delivery
For delivering therapeutic drugs, carbon nanofibers can be used. An elastic material embedded with CNFs that is like a needle has been developed. CNFs are used as balloons and are inserted next to the diseased tissue, then inflated, thus enabling CNFs to deliver drugs by penetrating the diseased cells.
For electrode materials
Effective surface area increases when CNFs grow on the surface of metal because of their metallic nature. Thus, Carbon nanofiber also has applications as a material of an electrode for supercapacitors and decoupling capacitors. Supercapacitors have a 100 times larger lifetime than batteries of lithium; they have high power density; they are electrochemical capacitors. Electrodes material’ effective area determines their performance. Carbon nanofiber’s flexible sheets are considered for supercapacitors as electrode materials due to their high electrochemical and mechanical stability, and pores that are interconnected very well.
As a Field electron emission source
Induced by an electrostatic field, field electron emission is the emission of electrons. Most commonly, field emission into a vacuum from a solid surface. Although, field emission can occur from liquid or solid surfaces into air, vacuum, a fluid, or any weakly or non-conducting dielectric. Electron’s field-induced promotion to the semiconductors’ band of conduction from the valence (the Zener effect) is another form of field emission.
Composite materials
Carbon-carbon-composite material can be manufactured by a process which includes the steps of treating a carbonaceous carrier material with a catalyst material that contains metal. Carbon structures of nanosize can be formed by this metal, and carbon structures of nanosize keep growing. This process allows surface chemistry, hydro-dynamical properties, and optimizing porosity independently from each other, which is specifically of significance in the use of the composite for purification of water. For applications as a filler, composites that are based on black Carbon are very useful.
For Gene delivery
Delivering genes via nanomaterials like carbon nanofibres is known as Impalefection. Nanostructures that are needle-like are produced perpendicular to the substrate’s surface. Plasmid DNA having the gene is made for intracellular delivery, by attaching itself to the surface of nanostructure. Against tissue or cells, a chip is pressed with these needles’ arrays, making cells impale. Delivered gene(s) can be expressed by Impaled Cells.
In 3D Printing
3D solid objects are made with the help of computers. Now, there are two methods of carbon nanofiber printing: continuous carbon nanofibers reinforcement, and thermoplastic filled with chopped carbon nanofiber. CNF is used in both methods. Still, there is a huge difference between them. Even though for prototype’s production, the good option is chopped CNF, but as the parts of metal need higher strength, that’s why for their production, continuous CNF is the most used method. Chopped CNF consists of little pieces that are adhered together, while in continuous CNF, a continuous connection is formed.
Sensors
By testing the differences of electrical properties that have come out as a result of altered external conditions, which also include stress or strain and the gas environment, we can normally do the self-sensing function of CNF compositions. If the external conditions are reversed, they can also reverse the electrical conductivity of the CNF composites due to the reversible change of quite a few orders of its magnitude. The very high electrical conductivity of this same composite upon stretching is also capable of reversing the high orders of its magnitude. CNF has been assembled as a gas sensor. According to this study, five orders of magnitude change of the electrical conductivity can be easily used to detect the vapor. CNF toxic gas sensor had as well been forged to recognize the irritant gas, such as NH3 and HCl, through a one-step vapor deposition polymerization method. Along with that, from the strain/stress or gas sensing, the temperature, humidity, magnetic field, and light are all such important elements that are required to be sensed in many applications.
Batteries
For batteries to show high performance and for supercapacitors, the main requirement is electrode materials that are highly porous, and are capable of containing enough electrolytes and satisfy the long-term and fast ion transport. The porous CNF has magnified surface areas. CNF axis’ direction is vertical to the nanosheets of graphene, which is capable of controlling the lithium ion’s diffusive orientation. Their structure overcomes the shortcoming of polysulfides random diffusion in the organic electrolyte without any sacrifice. Sensors are being made with the use of Nanofibers when chemical vapors are absorbed by the sensors; they change color. For lithium-ion batteries that are rechargeable, they were used as anodes.
Conclusion
Carbon nanofibers (CNF) are non-continuous, sp2-based linear filaments. Due to CNFs remarkable physicochemical properties, low cost, small dimensions, and nanosized diameter, which allows them to be used in electrode materials of energy storage devices and supercapacitors, filler in carbon-fiber-reinforced plastics, bone tissue scaffold, multifunctional composites, additives for batteries of lithium-ion, for metal particles the materials that are supporting, in scanning probe microscopy (SPM), in field electron emission sources, in implafection, and so much more.
USİNG NANOTECHNOLOGY TO IDENTİFY THOSE MOST AT RİSK FROM COVID-19
Current Strategies for Vaccine Trial and Production
It’s now obvious that the pandemic of COVID-19 is the number one concern for everyone from all over the world as the surge of Coronavirus has led to the closedown of proactive closure of schools and universities and the lockdown of many cities in all four corners of the world. Furthermore, many scientific conferences have been called off and the global economy has seriously been affected due to the consequences of the outbreak. In order to get over the problem, several biopharmaceutical companies and research organizations namely Moderna/National Institutes of Health (NIH), Medicago, Inovio, Clover/GSK and the Chinese Academy of Military Medical Sciences have claimed the synthesis of the potential COVID-19 candidates. In so doing, some of the mentioned scientific organizations have already started their clinical trials as well. Nevertheless, it is estimated that the process of clinical trials could take 12 to 18 months in order to achieve the production and distribution of COVID-19 vaccine across the world 1.
Old Viral Medication Trials
The reintroduction of the existing antiviral strategies and vaccines could also be an alternative and a shortcut until the vaccines have been finalized. Chloroquine, which has already been approved by the U.S. Food and Drug Administration for malaria treatment, has shown to inhibit endocytosis of nanoparticles in the sizes as big as that virus. For quite a while, it was believed that it could be consumed potentially against the COVID-19 and was put in practice for the treatment in China. Later, it was revealed that chloroquine is not a practically efficient agent but shows satisfactory results with minor side effects according to reports.
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Nanotechnological Viewpoint towards COVID-19 Treatment
There are now investigations and clinical experiments concerning the effects of several potential drug and therapies. Remdesivir among all, has shown much more satisfactory outcomes in vitro and in vivo experiment against the Coronavirus family pathogens. The need for antibodies in conjunction with other testing regimes is essential in order to confirm infections since titers antibody are left undetected in the course of the first few days of the infection. However, immunoassays conducted based on straightforward chemiluminescence operation and probe-based colloid nanoparticles immunoassays make it possible to carry out immediate identification of asymptomatic patients and those with mild symptoms leading to the immediate contact tracing/mandated quarantine consecutively. At the moment, antibody test kits are being developed to facilitate the self-diagnosis at home. The examination of nucleic acids based on a reverse transcription polymerase chain reaction as well as next-generation sequencing combined with detecting antibodies can considerably promote the isolation rate and identification. Furthermore, antibodies quantification against COVID-19 can potentially lead to evaluation of whether a convalescent survivor can donate convalescent plasma or not. Moreover, diagnoses based on identification of viral proteins are under investigation and will make it possible carry out fast diagnosis with no hesitation using a simple setup 1.
Nanotechnology and nanoscience as a whole have the potential to study systems and organisms whose properties change according to their size. For instance, if you can conduct a reaction in a flask of 500 µL up to 10 mL, the result of the reaction will be almost the same. However, in the case of choosing nanoscale sizes and containers, the interaction between the walls of the container and the reagents become sort of relevant and therefore, in such a condition the container size will appear to play a critical role in the chemistry of the reaction.
COVID-19 Identification Techniques Based on Nanotechnology in High-Risk Individuals
It is argued that the best technique to take the control of COVID-19 in the absence of practical vaccines has to be a reliable cheat, portable diagnostic device. Recently, a study has revealed the possibility of new approach based on nanotechnology. Developing plug-and-play diagnostics to control the COVID-19 outbreak could come in efficient in preventing the surge of epidemics in the future. Researchers from Michigan State University state there are pre-existing comorbidities among patients at high risk of COVID-19 infection. In addition, the identification of patients at serious risk of COVID-19 mortality, especially those with comorbidities including progressive respiratory failure, cardiovascular disease and massive alveolar damage, could remarkably strengthen health care providers and increase their resistance in order to take immediate actions and minimize any overwhelming care centers and consecutively save those with critical conditions. It is necessary to have a complementary technique for an early identification. It is considered crucially important to evaluate the risk of mortality before the progression of the disease in order to protect healthcare resources and lower death toll. On the other hand, it is impossible to categorize patients with a high risk of life-threatening condition and those with asymptomatic carriers different from clinical observations where there more reliable and faster strategies are required. Basically, there are two major areas for any possible point-of-care diagnostics in the case of COVID-19 with high risk as magnetic levitation and bimolecular Corona 2.
Nanoparticles Identification Mechanism
Once a nanoparticle enters into the human blood or any biological environment, it engages in an immediate contact with a variety of biomolecules, more importantly, protein which create a coating layer on the surface of the nanoparticle giving rise to the so-called biomolecular corona importing a unique biological characteristics and identity to the nanoparticle which is particularly distinct form that of the original nanoparticle surface. It has also been demonstrated that the combination with advanced classifiers and the protein corona with the relevant specific disease can help detect and discriminate cancers prior to their occurrence. Similarly, there is a technique that could be employed for precise discrimination between nonfatal and fatal COVID-19 infection considering the fact that the common cold is capable of altering the profile of protein corona at the surface of polystyrene and silica nanoparticles. A technology known as protein corona sensor array is capable of defining the plasma protein/biomolecule patterns to identify life-threatening case of COVID-19 infection at practically early stages. Even though the surface of biomolecular corona is covered by proteins, other biomolecules including nucleic acids, metabolomes and lipids possess diagnostic capabilities in the corona composition. Considering the fast point-of-care testing, the application of fluids with biological grades such as urine, saliva and tears could be taken into account in protein coronavirus sensory techniques as these biological systems contain mostly the disease-related protein markers 2.
The application of biological fluids that are easy to gather any platform with discriminative capabilities is the purpose behind creating a point-of-care in the absence of a healthcare expert compared to human plasma which requires a blood sample to be taken by an expert. However, the major downsize of biological fluids with known plasma nature compared to human is plasma they appear to contain smaller quantities and range of biomolecules leading to poor sensitivity and specificity to be applied in a precise prediction.
Conclusion
The suggested mechanisms and approaches might eventually lead to a sensitive and simple system to precisely identify patients with positive COVID-19 cases at high risk of fatality. This viewpoint could remarkably promote strategies towards any probable future pandemic and healthcare resources as well as management strategies without suffering from the large social and economic burden the world is facing today.
CARBON NANOTUBE (CNT) SPONGES
Carbon Nanotube (CNT) Sponges
Carbon nanotubes (CNTs) are nanoscale, strong and hollow cylinders which shows excellent mechanical and electrical properties. Based on their orientation and configuration in the structure, they can be used in many practical applications such as supercapacitors, catalytic electrodes, flexible heaters, superhydrophobic coatings, biomimetic surfaces, artificial muscles, and integrated microelectromechanical systems. These different forms of CNTs can be vertically aligned arrays via direct growth, long fibers or sheets yarned from CNT forests, solids and wafers densified from aligned films, solution-processed aerogels and thin films. All of these forms of CNTs show different properties since their alignments, densities and porosities are different. CNTs can be considered as superior sorbents for a wide range of organic chemicals and inorganic contaminants than conventional systems such as clay and activated carbon, with a number of advantages including stronger chemical-nanotube interactions, rapid equilibrium rates, high sorbent capacity and tailored surface chemistry.
Figure 1: Schematic Representation of a Single-walled Carbon Nanotube (SWCNT)
NT sponges are made up of interconnected carbon nanotubes where the CNTs are self-assembled into a three-dimensionally interconnected framework. CNT sponges are novel materials that are low density, lightweight, high surface area and high porosity which makes them useful in many applications. Their porosity is larger than %99. Also, they have very high structural flexibility, robustness and wettability to organics. The structural integrity under large deformations is owing to the highly interconnected CNTs in a three-dimensionally isotropic configuration, which could prevent the sliding or splitting between CNTs along any direction They can be deformed into any shape elastically by applying very large strains. They can absorb wide range of solvents and oils with excellent selectivity, recyclability, and absorption capacities up to 180 times their own weight which makes them an outstanding candidate for the environmental clean-up applications.
Figure 2: Schematic representation of Carbon Nanotube Sponges
CNT sponges are produced by chemical vapor deposition (CVD) method in which a precursor solution of ferrocene in dichlorobenzene was injected for four hours. The CNT sponges display structural flexibility that was rarely observed in other high-porosity materials (e.g., aerogels) or aligned CNT arrays. Manual compression to >50% volume reduction shows that the sponge is malleable and springy. A bulk sponge can be bent to a large degree or twisted without breaking apart, and after that still recover to nearly original shape. The conservation of structural integrity after large deformations is owing to the highly interconnected CNTs in a three-dimensionally interconnected framework, which could prevent the sliding or splitting between CNTs along any direction.
In addition to superior mechanical properties of CNT sponges, their high electrical conductivity is also another superior property that makes them an outstanding candidate for many applications. Besides their environmental clean-up applications such as large area oil spill cleanup, purification of water, and treatment of waste oil since they are highly hydrophobic and oleophilic materials, they can be used in sensors, smart materials and compressible conductors due to their high electrical conductivity.
Figure 3: Carbon Nanotube Sponges
nother important property of these CNT sponges is that they can be ferromagnetic by filling iron into the small capsules within a single carbon shell in the synthesis process. This property can be used to direct CNT sponge or control their whereabouts. Thus, they can be separated with the help of a magnet from oil, water or any liquid which is beneficial for cleaning oil spills or water purification. CNT sponges are not only used to absorb oil, they could also potentially be used to remove bacteria or contaminants from other liquids. In the case of a fuel spills, CNT sponges can absorb fuel from the water and this absorbed fuel can be used by burning the CNT sponge. At the end of this burning process CNT sponges can be used again which implies their reusable feature.
Compared to other conventional cellular materials, CNT sponges show excellent mechanical properties and high stability: high strength-to-weight ratio, superelasticity, thermomechanical strength over a wide temperature range, very low stress relaxation under high pressure, excellent resistance to fatigue and electromechanical stability under mechanical compression. The sponge structure is uniform with excellent mechanical strength, excellent flexibility, high porosity and low density.
CNT sponges are great thermal insulators. Although carbon nanotubes are good thermal conductors, CNT sponges are thermal insulators due their highly porous nature. Their thermal conductivity is lower than other insulators such as foams or woods. Therefore, superior properties of CNT sponges such as good thermal stability, electrical conductivity, robustness, resistance against harsh environment and super-elasticity makes them candidate material for many applications.
As mentioned above, CNTs can be transformed into different shapes such as sheets, long fibers, thin films, sponges etc. Depending on the orientation and shape of the CNTs application are could vary. CNT sponges could be an alternative material which for many applications. CNT sponges could be used in environmental applications such as sorption, filtration and separation. Also, they could be used in batteries. These applications are mentioned below.
Oil Spill Cleanup
Oil spills, defined as the leakage of petroleum onto the surface of large bodies of water, are a major global issue. There are a multitude of causes that contribute to the severity of this problem, including the drilling of petroleum carried out in or near the sea, the leakage of fuel from water sports or vehicles, leakage of products containing petroleum on land into the ocean, and equipment faults of oil tankers. Combined with the natural seepage from the ocean, these sources add to the world’s waterways at a rate of 3.5 to 6 million metric tons a year. Scientists have attempted to search for a method that can effectively clean the spill and help to alleviate the damage. Although many methods have failed, in recent decades, scientists have spent much time altering the structure of carbon nanotubes. Carbon nanotubes have acquired the potential to be used as one of the primary processes for cleaning up oil spills. They originally caught the attention of scientists due to their high strength, conductivity, as well as their lightweight structure. By altering the structure of the carbon nanotube in this way, it begins to grow into a woven sponge-like material that is three-dimensionally strong and efficient at absorbing oil because it attracts oil while repelling water. Also, ferromagnetic properties of CNT sponges allow for easy control or removal externally during the cleanup of oil spills. Therefore, CNT sponges could be a solution for oil spills due to its low density which allow for CNT sponges to float on the surface of the water by absorbing only the oil. Other properties such as large surface area, high porosity and elasticity make CNT sponges potential solution for these problems.
Figure 4: Deep Water Horizon Oil Spill Disaster (2010)
Water Purification
CNT sponges can absorb any other organic contaminants present in water. These features can be used in the purification of polluted water which occurs as a result of an industrial accident or marine litter. Once CNT sponges are saturated with oil, oil can be eliminated by quickly squeezing the sponge and releasing the oil, the sponges can then be used again. Moreover, CNT sponges can absorb fuel present in water can be used by burning CNT sponge which will conserve its structure and properties after burning the fuel. It can be used again and again.
Catalyst
CNT sponges are alternative materials for catalysis, acting either as catalyst themselves or as active sites for selected catalysts. High surface area of CNT sponges offer large number of active sites and they can boost reaction kinetic due to its high electrically conductive nature. Also, their mechanical and chemical stability increases cycle life of catalysts.
Energy Storage
CNT sponges can be used in Li-ion batteries in the bulk form instead of graphene which is used nowadays. In Li-ion batteries, Li ions are passed through electrolyte to the graphene structure to be stored. This process is called intercalation. They are stored in negative electrodes. Negative electrode should have high specific surface area, mechanical strength, chemical stability and electrically conductive for the electron transfer. CNT sponges offer these properties which boost battery performance by providing high energy density, high C-rate capability and long cycle life.
Conclusion
Carbon nanotube sponges (CNTs) are materials made up of CNTs which are interconnected in 3-D framework. CNT sponges are produced by chemical vapor deposition (CVD). Their superior properties such as high surface area, high porosity, low density, high strength to weight ratio etc. make them candidate or alternative material for many applications. In addition to these properties, their mechanical and chemical stability, being ferromagnetic material or being thermal insulator boost the performance of CNT sponges for a chosen application.
Due to hydrophobic and oleophilic nature of CNT sponges, application areas of CNT sponges range from environmental cleanup to high-tech applications such as smart materials, sensors or batteries. All in all, CNT sponges are novel materials to be used in various applications that have gained interest for the last years.
NANOTECHNOLOGY İN AGRİCULTURE
Nanotechnology in Agriculture
The improvement in agriculture is crucial for the resolving of problems that comes with increasing food consumption. Nanotechnology offers promising results in the improvement of key aspects in agriculture such as soil quality, agrochemical efficiency, environmental protection, and animal production efficiency. Of course, possible toxic effects of nanomaterials must be assessed properly.
The global population has been rapidly increasing each year and has reached 7.8 billion as of July 2020 with 59% living in Asia. This number is expected to reach 9.5 billion by 2050. One of the most significant effects of an increasing global population is accordingly increasing food consumption and the importance of agriculture. Agriculture is the largest interface between nature and human species meeting the nutritional demands of the ever growing population on earth. However, several challenges and problems in agriculture need tending and development in order to meet the great food demand while also preserving nature. Aside from the obvious increasing food demand, there are also problems with food shortages due to environmental effects such as poor feed quality, animal diseases, storms, poor soil quality, droughts, and floods in developing countries where a considerable portion of the global population lives. These problems are also accompanied by the limit of natural resources such as production land, water, soil, etc. The competition between the industry and agriculture for the limited production land has left little room for the agricultural activities with the growing popularity of the industry. The combined effect of all these problems in agriculture requires urgent development in agricultural studies to increase the efficiency and volume of agricultural production while decreasing the required production land area. Another concern related to agricultural activities is the negative effect of agrochemicals on the environment due to the agglomeration of these powerful chemicals such as pesticides and fertilizers. Nanotechnological solutions have been investigated as a way to overcome the crucial problems in agriculture. Improving soil quality is perceived as the first step to improve agricultural activities in terms of farming. Hence, several different nanotechnological solutions such as hydrogels, nanoclays, and nanozeolites have been suggested to enhance the water holding capacity of soil along with nanopolymers, carbon nanotubes, metal, and metal oxide nanoparticles which are used in the removal of environmental contaminants. Further applications of nanotechnology are related to enhanced agrochemicals, monitoring of chemicals, soil and water treatment, and animal production. Of course, all these possible applications of nanotechnology require a detailed assessment of toxic effects on human health and the environment in order to achieve feasible applications.
Nano-inspired Agrochemicals
Agrochemicals such as pesticides and fertilizers are important players in agricultural activities. However, when agrochemicals are applied through conventional methods they are prone to decompose rapidly or to be removed by external factors such as wind, sunlight, and rain. Due to the inefficient use of agrochemicals in conventional methods, most of these chemicals cannot reach the targeted species and become useless. Periodic application is required to make up for unused agrochemicals which increases the negative environmental effect of these chemicals. On the other hand, nanotechnology inspired agrochemicals show great potential to overcome these challenges due to their enhanced properties in nano-scale. Therefore, nanofertilizers and nanopesticides have recently attracted a lot of attention.
On the road to sustainable agriculture, the development of nanofertilizers is regarded as a promising approach. Nanofertilizers significantly increase plant growth and product yield while supporting environmental protection. Thanks to nanotechnology, the nutrients are released s into the soil gradually and in a targeted/controlled manner. This may prevent eutrophication and run-off causing water and soil pollution. In nanofertilizer materials nutrients can be encapsulated by nanomaterials, coated with a thin protective nanoscale polymeric film, or delivered as nano-emulsions or nanoparticles (NPs) Nanofertilizers may contain nano zinc, silica, iron and titanium dioxide, ZnCdSe/ZnS core-shell QDs, InP/ZnS core-shell QDs, Mn/ZnSe QDs, zeolites, carbon nanotubes (CNTs) and gold nanorods. These complexes can supply one or more nutrients to the plants and enhance their growth, or can improve the performance of conventional fertilizers. Nanofertilizers increase plant-uptake efficiency of nutrients and reduce the adverse impacts of conventional fertilizer application. High specific surface area and enhanced surface chemistry of nanomaterials provide high nutrient intake and gradual release of the nutrients which reduces nutrient loss as well as environmental risks. Zeolites are an important example of such nanomaterials providing high specific surface area and d a high selection toward plant macronutrients. On the other hand, titanium oxide (TiO 2) and CNTs containing nanofertilizers improve the plant photosynthesis efficacy and enzyme activity without the need for essential nutrients which leads to an increase in plant germination and growth. In addition to the engineered nanomaterials, nanoemulsions of macro or micronutrients are also utilized in nanofertilizers enabling the nutrient to be delivered homogenously and increasing the interaction surface between plants and nutrients.
Along with fertilizers, pesticides are important players in agriculture as well. Even though pesticides are essential, they pose a great threat to the environment and human health. Just as fertilizers, the ineffective delivery of pesticides creates the need for regular application and consequently a significant amount of accumulation in the soil and on the plants. This is why, nanoengineered pesticides, nanopesticides, have recently been suggested as a solution to these problems. Several different methods are pursued in nanopesticide applications. One of the nanopesticide applications includes carriers such as polymeric nanospheres, nanocapsules, nanogels, nanofibers, solid lipid nanoparticles, liposomes, or clay nanotubes (halloysite) for targeted delivery and controlled release of pesticide particles. On the other hand, engineered nanoparticles such as silver, copper, metal oxide nanoparticles, and nanoclay are also utilized as nanopesticides. Similar to fertilizers, pesticide molecules can also be incorporated into nanoemulsions and nanodispersions increasing the bioavailability of the active ingredient. Nanopesticides claim importance based on their ability to decrease the amount of active ingredient used, the release of harmful chemicals to non-target organisms thus reducing the development of resistance as well as their ability to provide greater solubility, mobility, and durability.
Nanotechnology for Monitoring Chemicals
The dependency on chemical materials in agriculture brings the necessity of environmental protection measurements since environmental security is an important matter considerably affecting the public well-being. Detection and monitoring of environmental pollutants caused by agricultural activities is a major part of assuring environmental security. The development of sensitive and selective monitoring systems is therefore crucial for environmental friendly agriculture. In this concept, enhanced chemical activity and surface area of nanomaterials is a great asset for real time monitoring of a wide variety of fertilizers, herbicide, pesticide, insecticide, heavy metals, organic pollutants, and pathogens. These “nanosensors” are analytical devices fabricated for monitoring physicochemical properties in places otherwise difficult to reach, offering greater sensitivity, low detection limits, selectivity, fast detection rates, and more portability than conventional detection techniques. These unique properties of nanosensors are also utilized for the improvement of detection limits for bacterial, viral, and fungal pathogen determination in plants. In addition to possible toxicants and pathogens, the soil quality in terms of moisture levels, soil pH, fertility and temperature, crop nutrient status, and concentrations can also be monitored with nanosensors. Therefore, a network of nanosensors providing analyses of different environmental, crop, and pest variables would create valuable data for agricultural activities. These analyses are great assets for choosing fertilization strategies, reduction of inputs, and better management of time and environmental resources. The most commonly studied nanomaterials in nanosensor applications are metal (gold, silver, cobalt, etc.) NPs, CNT, magnetic NPs, and QDs. Even though nanosensor studies have come a long way and shown great improvements, nanosensor systems still require a detailed investigation to assess sensitivity to common toxicant residues, pathogens, and environmental parameters, the need for a multi-residue identification in the real agricultural scenario, and the fabrication and validation of suitable detection instruments. Moreover, the effect of nanomaterials on the environment must be investigated thoroughly.
Nanotechnology for Water and Soil Treatment
So far we have established the importance of monitoring environmental pollution and the nanomaterials’ in this process. However, establishing an effective and holistic approach requires water and soil treatment processes in addition to the monitoring of pollutants. Soils and groundwater are contaminated by pollutants from natural and anthropogenic activities posing a great risk to human health or the environment. Agriculture is both the source of this pollution and affected by polluted soil and water. Hence, developing water and soil treatment processes is indispensable. The studies on this subject have recently focused on nanotechnology and nano engineered materials hoping to develop new cost-effective and powerful methods. Soil and water treatment involves the removal of pollutants such as heavy metals/metalloids, dyes, and organic pollutants. Nano-remediation works through transformation and detoxification of these pollutants with the use of reactive nanospecies. The high surface area of nanomaterials enhances the chemical activity of remediation materials while small-sized materials enable a wider distribution compared to larger, macro-sized particles. Nano-remediation has the potential to reduce the overall costs of cleaning up large-scale contaminated sites, reduce clean-up time, eliminate the need for treatment and disposal of contaminated soil, and reduce some contaminant concentrations to near zero-all in situ.
Various nanoparticles including metal, metal-oxide, and bimetallic NPs, carbon nanotubes and fibers have been investigated for soil and water treatment. Amongst these options, zero-valent iron nanoparticles (ZVI-NPs) have attracted considerable attention due to their low cost and low toxicity. ZVI-NPs acting as electron donor molecules in redox reactions are effective in the removal of heavy metals and chlorinated particles from soil and water. Furthermore, ZVI-NPs are utilized in the elimination of nitrogen from activated sludge and phosphorus from wastewater. However, the rapid agglomeration and possible reaction with undesired species have limited the wide range use of ZVI-NPs. Another promising group of nanomaterials in soil and water treatment is metal-oxide nanoparticles such as magnetite (Fe 3O4), aluminum/titanium containing composites (Al 2O3/TiO2), bimetallic composites, and carbonaceous nanomaterials. Magnetite or other iron oxides are advantageous due to their redox cycle, ion exchange, high affinity for contaminants, and magnetic properties. These magnetic properties of iron oxides provide ease of removal from the water after the treatment process making it an easy cost-effective method. Bimetallic compounds consisting of iron and different metal such as palladium, silver, and nickel are also utilized in soil and water treatment for the removal of dyes, heavy metals, and halogenated compounds. Ag/Fe composites are especially effective in the antibacterial treatment of water. These composites can be treated with carboxymethyl cellulose, polymers, and surfactants for better stabilization and prevention of agglomeration. Al 2O3/TiO2 is considered in the removal of heavy metals such as lead and cadmium from soil and water. However, metallic compounds require caution due to their possible toxic effects and reactive nature with undesired targets. Carbonaceous nanomaterials are valuable assets in the removal of undesired organic compounds such as halogenated organics, polychlorinated biphenyls, polycyclic aromatic hydrocarbons, and volatile organic compounds as well as herbicides, industrial dyes, and heavy metals in water. Nanomaterials worth the attention not just for their unique properties but also for their ability to work in-situ or ex-situ depending on the requirement. However, there are still aspects of nano-remediation methods that need improvement including regeneration and reusability, large-scale application, and efficiency in wastewaters and contaminated soils. Furthermore, their applicability in-field must be further investigated to develop feasible systems.
Nanotechnology in Animal Production
Livestock, poultry, and aquaculture are also related to agriculture and constitute a big part of it. These agricultural activities play a great part in human nutrition and consequently have grown along with the increasing population. The main challenges in animal production are production efficiency, animal health, feed nutritional efficiency, diseases, product quality and value, by-products and waste, and environmental footprints. Nanotechnological solutions have been offered for all of these problems in animal production. Amongst all, feed efficiency arguably holds the most important place since it affects many other problems either directly or indirectly. Improving feeding efficiency reduces feed demand, waste production, environmental effects, and cost. Improving feed efficiency is especially important in developing countries where feed quality is usually is at undesired levels. Nanotechnology can be used to enhance the nutritious value and efficiency of feeds. Nano delivery systems such as micelles, liposomes, nano-emulsions, biopolymeric nanoparticles, protein-carbohydrate nanoscale complexes, solid nano lipid particles, dendrimers, and others have been developed for the efficient delivery of nutrients. These delivery systems provide better adaptability, high absorption, bioavailability, and better solubility increasing the feed efficiency. Improving feed efficiency also affects the product value and quality ensuring the production of animal-derived food in line with health recommendations and consumer expectations. These products help in the prevention of chronic human diseases such as cancer and atherogenesis For example, the nanotechnology-based delivery of nutrients helps to control the biosynthesis and concentration of CLA and VA in the milk fat. Similarly, the same delivery systems in nutrition delivery can be used for the selective drug delivery and controlled delivery of drugs in treatments or preventative applications improving the life quality of animals. Drugs and vaccines developed through nanotechnology are relatively more effective and cheaper than their conventional counterparts. Using nano-enhanced drugs requires less active ingredients reducing the environmental effects and possible antibiotic resistance. Nanotechnology is also employed in the diagnostics of common or crucial diseases such as bovine mastitis, tuberculosis, respiratory disease complex, Johne’s disease, avian influenza, mad cow disease, avian influenza, H1N1 influenza, Ebola virus, Nipah virus and porcine reproductive and respiratory syndrome (PRRS). Thanks to nanotechnology, the detection and diagnostics systems can become highly specific and sensitive, can detect multiple samples at a time, are time-saving, robust, have on-board signal processing, and are convenient to use, portable and economical.
Toxicological Concerns of Nanomaterials Used in Agriculture
Exposure to nanoparticles is not a new concept emerged with nanotechnology. Natural or industrial sources such as forest fires have been releasing nanomaterials to the environment long before the development of nanotechnology. The human body has developed mechanisms to reduce the effect of these nanomaterials and filter undesired particles while in nature the life span of these nanoparticles is considerably short due to agglomeration and dissolving in water. However, the response of the human body and environment to the engineered nanoparticles might be different due to their protective coatings and carefully adjusted sizes. This is why a detailed investigation of the toxicity of engineered-nanomaterials is crucial. Even though it is a complex mission, the relationship between the particles and biological reactivity as well as the dose-response relationship must be assessed carefully. The effect of nanomaterials becomes significant especially in the case of long term exposure which points out that occupational risk must be taken into consideration. Clearly, nanotechnological agriculture is a new field to be assessed and regulated according to comprehensive studies on the subject.
Conclusion
Agriculture is the backbone of human nutrition and has considerably grown with the growing global population. However, current agricultural methods are not sufficient enough to meet the demands of increasing population and the expectancy of society. Furthermore, conventional agrochemicals are ineffective and cause serious damage to the environment and human health because of recursive applications. This is why studies have been conducted to improve agricultural activities in terms of efficiency, cost, time-costs, and environmental effects. Amongst these studies, nanotechnology has recently attracted attention. Nanoengineered materials are utilized in improving soil quality, developing effective nanofertilizers and nanopesticides, monitoring chemicals both in soil and in aqueous media, water and soil remediation, and animal production. Soil quality is improved by incorporating water-holding materials such as zeolites and nanoclays as well as materials to eliminate contaminants from the soil. The star players of agriculture, fertilizers, and pesticides, have also been enhanced with the use of nanotechnology since the high surface area, chemical activity, and solubility of nanomaterials are desirable. Nanofertilizers and nanopesticides offer effective use and homogenous distribution of active ingredients, cost-effective application; reduce environmental damage by the strong chemicals in fertilizer and pesticides. The protection of the environment and human health begins with the monitoring and control of chemicals in soil and water. Nanotechnological solutions provide ease of operation during the monitoring process by enabling access to areas that are otherwise hard to reach as well as sensitivity and selectivity to the detection process. The next step in the protection of the environment and human health is the soil and water remediation. Nanotechnology also offers smart solutions to these processes during the extraction of undesired materials such as heavy metals, organic components, and dyes. Nanoparticles utilized in soil and water remediation are iron oxides, carbonaceous nanomaterials, bimetallic nanomaterials, and Al 2O3/TiO2. In addition to farming, animal production is also affected by nanotechnology especially in the improvement of feed efficiency, animal health, and ensuring product quality and value. Feed efficiency is improved by enriching the nutrient content of conventional feeds as well as using nano delivery systems. These systems include micelles, liposomes, nano-emulsions, biopolymeric nanoparticles, protein-carbohydrate nanoscale complexes, solid nano lipid particles, dendrimers, and others. Improving feed efficiency also affects the product value and quality ensuring the production of animal-derived food in line with health recommendations and consumer expectations. Animal health is a problem that influences steady production and causes economical damage. Nano drug delivery systems similar to nutrient delivery systems are utilized in the treatment of diseases while detection and diagnostic methods based on nanotechnology offer the development of specific, sensitive, effective, and portable equipment. Of course, such nanotechnological solutions still need a clear assessment of possible toxic effects of nanomaterials. All in all, it is clear that agriculture is an integral part of human life and nanotechnology has great potential for the improvement of the out-dated applications in agriculture.