Carbon Nanotube Concentration Measured in Plants for Nano-Pollution, Nanotoxicity
This invention uses microwave heating to detect carbon nanotubes in biological samples, measuring carbon nanotube concentration more effectively than current methods like electron microscopy and Raman spectroscopy.
Carbon nanotubes (CNT's) are made up of carbon atoms arranged in a cylindrical nanostructure. They are among the most widely used carbon-based nanomaterials. Nanotubes can easily penetrate membranes like the cell walls of plants. As a result, carbon nanotubes have enormous potential for use in agriculture as directed delivery systems for pesticides, fertlizers, and other chemicals.
To test the efficacy of the microwave technology, we injected alfalfa roots with carbon nanotubes and exposed them to a microwave field to calculate standard temperature to carbon nanotube concentration relationships. We then used these measurements to determine the degree to which the alfalfa plant’s roots absorbed carbon nanotubes. The demonstration showed that microwave heating could not only detect the presence of carbon nanotubes, but also accurately measure their concentration. Knowing the concentration of carbon nanotubes in plant roots, soil, air, and water is essential in assessing the risk of nano-pollution and determining levels for nanotoxicology.
Measuring Carbon Nanotube Absorption in the Environment
Agriculture in the United States uses thousands of chemicals every day. Many of these chemicals combine easily with organic carbon. As a result, farmers are increasingly interested in using carbon nanotubes as delivery mechanisms for agricultural pesticides. It is therefore important that we are able to evaluate the concentration of carbon nanotube taken into the roots of plants and their potential interactions with crop species and other organisms. The use of this microwave-heating technology effectively quantifies carbon nanotubes in plants and other biological samples in soil.
There have been numerous studies regarding the potential nanotoxicity and effect of carbon nanotubes on aquatic and terrestrial organisms and environments. However, a true understanding of nano-pollution has been hindered by the lack of reliable and affordable methods to analyze the concentration of carbon nanotubes in biotic and abiotic samples. This invention provides a low-cost, reliable way to measure nanomaterial concentration and provide information in nanotoxicology risk assessment.
The EPA and Nanotechnology
As more manufacturers use carbon nanotubes in electronics and other products, experts expect more nanomaterials to reach our water and soil. Until now there hasn’t been a reliable way to detect and quantify nano-pollution in the field. This cost-effective method could become the standard for EPA testing.
Wisconsin, California, and Massachusetts have already signed legislation addressing the environmental risk of nanotechnologies, and local governments have passed ordinances to address nanomaterials' to the public. At the moment, there are no EPA regulations on nanotechnology, largely because it has been impossible to detect nanomaterial absorption in the environment.
However, the EPA has recently begun to focus on the impact of nanotubes on people and the environment. The microwave heating method of detecting and quantifying carbon nanotubes in agricultural samples represents a breakthrough in understanding nanotoxicology.
Uses for Carbon Nanotubes
This microwave technology is inexpensive to develop and maintain. The results it produces are repeatable, reliable, and may be applied to other biological and environmental samples other than agriculture.
The data that this method gathers will be useful to a wide range of scientists, from environmental chemists or engineers to government scientists who create or use nanotubes and are charged with ensuring the safety of this nanomaterial. In addition, this technique will help researchers to determine concentrations of nanomaterials in toxicity studies.
The potential applications for nanotechnology detection are endless, and may have far-reaching effects in the realm of medicine, agrochemicals, and toxicology.