title: Tracking and quantification of single-walled carbon nanotubes in fish using near infrared fluorescence.
abstract: Detection of SWCNTs in complex matrices presents a unique challenge as common techniques lack spatial resolution and specificity. Near infrared fluorescence (NIRF) has emerged as a valuable tool for detecting and quantifying SWCNTs in environmental samples by exploiting their innate fluorescent properties. The objective of this study was to optimize NIRF-based imaging and quantitation methods for tracking and quantifying SWCNTs in an aquatic vertebrate model in conjunction with assessing toxicological end points. Fathead minnows (Pimephales promelas) were exposed by single gavage to SWCNTs and their distribution was tracked using a custom NIRF imaging system for 7 days. No overt toxicity was observed in any of the SWCNT treated fish; however, histopathology observations from gastrointestinal (GI) tissue revealed edema within the submucosa and altered mucous cell morphology. NIRF images showed strong SWCNT-derived fluorescence signals in whole fish and excised intestinal tissues. Fluorescence was not detected in other tissues examined, indicating that no appreciable intestinal absorption occurred. SWCNTs were quantified in intestinal tissues using a NIRF spectroscopic method revealing values that were consistent with the pattern of fluorescence observed with NIRF imaging. Results of this work demonstrate the utility of NIRF imaging as a valuable tool for examining uptake and distribution of SWCNTs in aquatic vertebrates.
authors.affiliation: Department of Environmental and Global Health, Center for Environmental and Human Toxicology, University of Florida , 2187 Mowry Road, Box 110885, Gainesville, Florida 32611, United States.
authors.forename: Joseph H
authors.initials: JH
authors.lastname: Bisesi
authors.forename: Jonathan
authors.initials: J
authors.lastname: Merten
authors.forename: Keira
authors.initials: K
authors.lastname: Liu
authors.forename: Ashley N
authors.initials: AN
authors.lastname: Parks
authors.forename: A R M Nabiul
authors.initials: AR
authors.lastname: Afrooz
authors.forename: J Brad
authors.initials: JB
authors.lastname: Glenn
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Klaine
authors.forename: Andrew S
authors.initials: AS
authors.lastname: Kane
authors.forename: Navid B
authors.initials: NB
authors.lastname: Saleh
authors.forename: P Lee
authors.initials: PL
authors.lastname: Ferguson
authors.forename: Tara
authors.initials: T
authors.lastname: Sabo-Attwood
mesh_terms: D000818:Animals; D003530:Cyprinidae; D004784:Environmental Monitoring; D005399:Fishes; D005453:Fluorescence; D037742:Nanotubes, Carbon / Q000032:analysis*; D061848:Optical Imaging / Q000295:instrumentation / Q000379:methods*; D013050:Spectrometry, Fluorescence; D019265:Spectroscopy, Near-Infrared
chemical_list: D037742:Nanotubes, Carbon