Plant and Microbial Growth Responses to Multi-Walled Carbon Nanotubes Keita K, Okafor F*, Nyochembeng L, Overton A, Sripathi VR and Odutola J Department of Biological and Environmental Sciences, Alabama A&M University, Alabama, USA *Corresponding author: Okafor F, Department of Biological and Environmental Sciences, Alabama A&M University, Alabama, USA, Tel: 256-372-4422; E-mail: florence.okafor@aamu.edu Received date: May 8, 2018; Accepted date: May 23, 2018; Published date: May 30, 2018 Copyright: © 2018 Keita K, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Abstract Carbon nanotubes, made of graphene, one of the world’s strongest material, has shown properties that are used in applications such as energy storage devices, electron emission devices, and environmental engineering application. Recently, researchers have focused on determining the effects of carbon nanotubes on soil microorganisms and plants. Objective: The purpose of this study was to determine if the multi-walled carbon nanotubes will affect the growth of Phaseolus vulgaris as well as inhibit the growth of select soil microbes. Methods: The effects of Multi-Walled Carbon Nanotubes were determined on bean plants grown under hydroponic conditions and on select soil microbes. Two weeks after germination, the plants were exposed to different concentrations of dispersed multi-walled carbon. The different concentrations were 0 ug (control), 50 µg, 250 µg, 500 µg, 750 µg and 1000 µg mLˉˡ. The growth was reported weekly by measuring the plants themselves, the diameter of the leaf, length and width, the roots, and the fruits. Cultures of Mesorhizobium sp. and Nitrosomonas stercoris were exposed to the 0 µg (control), 50 µg, 250 µg, 500 µg, 750 µg and 1000 µg mLˉˡ of dispersed MWCNTs then incubated in the BioScreen reader. The optical density was reported every 30 minutes for 24 hours. Results: Our results showed that at 50 µg/mL, bean plants exhibited tolerance to the multi-walled carbon nanotubes whereas at 250 µg/mL and 500 µg/mL of MWCNTs plants showed reduced growth and development and even plant death. Aliquots of 750 µg/mL and above of MWCNTs lowered the microbial biomass. The presence of high concentrations of carbon nanotubes is likely to cause stress to microbes and the direct contact of CNTs with microbes could damage their cell membrane leading to cell death. Conclusion: As results of this study, the concentration of multi-walled carbon nanotubes should be set at a maximum of 500 µg mLˉˡ when being released to the soil or environment. Keywords: Multi-Walled Carbon Nanotubes; Graphene; Nanomaterials; Phaseolus vulgaris; Bush Bean; Mesorhizobium sp; Nitrosomonas stercoris Introduction Nanotechnology cuts across all science felds (chemistry, biology, physics, materials science, and engineering). Tis growing feld has become a key empowering innovative tool in the industry because of its high application abilities. It is now utilized as a part of electronic, health services, chemical, beauty care products, composites and energy [1]. Nanoparticles (also known as inorganic materials), the most fundamental component in the production of a nanostructure, are particles with a nominal diameter (such as geometric, aerodynamic, mobility, projected-area or otherwise) less than one hundred nanometers [1]. Tey are also defned as a sub-classifcation of ultrafne particles with the size range of about 1-100 nm [2]. Many properties and applications of nanotechnology have been discovered recently which are contributing to major changes in the global economy. In medicine, the applications of nanotechnology are used to detect and treat human body diseases at cellular levels. In electronics, nanomaterials are used to display screens by reducing the power consumption, weight, and thickness of the screens, therefore making it less expensive. Nanomaterials are used in fuel cells, solar cells, batteries, and spacecraf, to limit the carbon emission, to enhance air quality, to produce cleaner water, chemical sensors, in fabrics and sporting goods. In food science, nanotechnology is developing materials such as Nano food packaging materials that may extend food shelf-life, improve food safety, alert consumers that food is contaminated or spoiled, repair tears in packaging, and even release preservatives to extend the life of the food in the package [3]. For example, clay nanoparticles are used to provide impermeability to gases such as oxygen and carbon dioxide. Silicate nanoparticle is used as a barrier to gases to prevent food from spoiling or drying. Carbon nanotubes can be used as chemical and mechanical sensors because of their small size. Also, carbon nanotubes are used in Smart packaging (plastic food wrap) as gas sensors that could enhance food safety and reduce the amount of food that is wasted [4]. Silver nanoparticles are now used in agriculture because of its property of killing pathogenic J o u r n a l o f N a n o s c i e n c e s : C u r r e n t R e s e a r c h ISSN: 2572-0813 Journal of Nanosciences: Current Research Keita et al., J Nanosci Curr Res 2018, 3:2 DOI: 10.4172/2572-0813.1000123 Research Article Open Access J Nanosci Curr Res, an open access journal ISSN: 2572-0813 Volume 3 • Issue 2 • 1000123