title: ROS evaluation for a series of CNTs and their derivatives using an ESR method with DMPO.
abstract: Carbon nanotubes (CNTs) are important materials in advanced industries. It is a concern that pulmonary exposure to CNTs may induce carcinogenic responses. It has been recently reported that CNTs scavenge ROS though non-carbon fibers generate ROS. A comprehensive evaluation of ROS scavenging using various kinds of CNTs has not been demonstrated well. The present work specifically investigates ROS scavenging capabilities with a series of CNTs and their derivatives that were physically treated, and with the number of commercially available CNTs. CNT concentrations were controlled at 0.2 through 0.6 wt%. The ROS scavenging rate was measured by ESR with DMPO. Interestingly, the ROS scavenging rate was not only influenced by physical treatments, but was also dependent on individual manufacturing methods. Ratio of CNTs to DMPO/ hydrogen peroxide is a key parameter to obtain appropriate ROS quenching results for comparison of CNTs. The present results suggest that dangling bonds are not a sole factor for scavenging, and electron transfer on the CNT surface is not clearly determined to be the sole mechanism to explain ROS scavenging.
authors: Shinshu University, Research Center for Exotic Nanocarbons, 4-17-1 Wakasato, Nagano, Japan.
authors: S
authors: S
authors: Tsuruoka
authors: Shinshu University, Faculty of Engineering, Research Center for Exotic Nanocarbons, 4-17-1 Wakasato, Nagano, Japan.
authors: K
authors: K
authors: Takeuchi
authors: Shinshu University, Faculty of Engineering, Research Center for Exotic Nanocarbons, 4-17-1 Wakasato, Nagano, Japan.
authors: K
authors: K
authors: Koyama
authors: Shinshu University, Research Center for Exotic Nanocarbons, 4-17-1 Wakasato, Nagano, Japan.
authors: T
authors: T
authors: Noguchi
authors: Shinshu University, Research Center for Exotic Nanocarbons, 4-17-1 Wakasato, Nagano, Japan.
authors: M
authors: M
authors: Endo
authors: Shinshu University, Research Center for Exotic Nanocarbons, 4-17-1 Wakasato, Nagano, Japan.
authors: F
authors: F
authors: Tristan
authors: Shinshu University, Research Center for Exotic Nanocarbons, 4-17-1 Wakasato, Nagano, Japan.
authors: M
authors: M
authors: Terrones
authors: Department of Organic and Polymeric Materials Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo, JAPAN.
authors: H
authors: H
authors: Matsumoto
authors: Department of Applied Physical Therapy, Shinshu University, School of Health Sciences, 3-1-1 Asahi, Matsumoto, Nagano, Japan.
authors: N
authors: N
authors: Saito
authors: Shinshu University, Faculty of Engineering, Research Center for Exotic Nanocarbons, 4-17-1 Wakasato, Nagano, Japan.
authors: Y
authors: Y
authors: Usui
authors: National Institute for Occupational Safety and Health, Morgantown, WV, USA.
authors: D W
authors: DW
authors: Porter
authors: National Institute for Occupational Safety and Health, Morgantown, WV, USA.
authors: V
authors: V
authors: Castranova