title: Toward tailored functional design of multi-walled carbon nanotubes (MWNTs): electrochemical and antimicrobial activity enhancement via oxidation and selective reduction.
abstract: Multiwalled carbon nanotubes (MWNTs) are utilized in a number of sectors as a result of their favorable electronic properties. In addition, MWNT antimicrobial properties can be exploited or considered a potential liability depending on their intended application and handling. The ability to tailor electrochemical and antimicrobial properties using economical and conventional treatment processes introduces the potential to significantly enhance product performance. Oxygen functional groups are known to influence several MWNT properties, including redox activity. Here, MWNTs were functionalized with oxygen groups using standard acid treatments followed by selective reduction via annealing. Chemical derivatization coupled to X-ray photoelectron spectroscopy was utilized to quantify specific surface oxygen group concentration after variable treatment conditions, which were then correlated to observed trends in electrochemical and antimicrobial activities. These activities were evaluated as the potential for MWNTs to participate in the oxygen reduction reaction and to have the ability to promote the oxidation of glutathione. The compiled results strongly suggest that the reduction of surface carboxyl groups and the redox activity of carbonyl groups promote enhanced MWNT reactivity and elucidate the opportunity to design functional MWNTs for enhanced performance in their intended electrochemical or antimicrobial application.
authors.affiliation: Department of Chemical and Environmental Engineering, Yale University , New Haven, Connecticut 06520-8286, United States.
authors.forename: Leanne M
authors.initials: LM
authors.lastname: Gilbertson
authors.forename: David G
authors.initials: DG
authors.lastname: Goodwin
authors.forename: André D
authors.initials: AD
authors.lastname: Taylor
authors.forename: Lisa
authors.initials: L
authors.lastname: Pfefferle
authors.forename: Julie B
authors.initials: JB
authors.lastname: Zimmerman
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology*; D055664:Electrochemical Techniques / Q000379:methods*; D004583:Electrons; D005978:Glutathione / Q000378:metabolism; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010084:Oxidation-Reduction / Q000187:drug effects; D010100:Oxygen / Q000737:chemistry; D056951:Photoelectron Spectroscopy
chemical_list: D000890:Anti-Infective Agents; D037742:Nanotubes, Carbon; D005978:Glutathione; D010100:Oxygen