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Flourescently labeled cellulose nanofibers for environmental health and safety studies



Jeremiah Woodcock, Ilabahen A. Patel, Ryan Beams, Stephan J. Stranick, Jeffrey W. Gilman, Douglas M. Fox, Marina Mulenos, Christie Sayes, Maryam Salari, Deloid Glen, Philip Demokritou, Bryan Harper, Harper Stacey, Ong Kimberly, Jo Anne Shatkin


An optimal methodology for locating and tracking cellulose nanofibers (CNF) in vitro and in vivo is crucial to evaluate the environmental health and safety properties of these nanomaterials. Here, we report the use of a new boron-dipyrromethene (BODIPY) reactive fluorescent probe, meso- DichlorotriazineEthyl BODIPY (mDTEB), tailor made for labeling CNF used in simulated or in vivo ingestion exposure studies. Time-correlated single photon counting (TCSPC) fluorescence lifetime imaging microscopy (FLIM) was used to confirm covalent attachment and purity of mDTEB labeled CNF. The photoluminescence properties of mDTEB labeled CNF, characterized using fluorescence spectroscopy, include excellent stability over a wide pH range (pH2 to pH10) and high quantum yield, which provides detection at low (M) concentrations. FLIM analysis also showed that lignin-like impurities present on the CNF reduce the fluorescence of the mDTEB labeled CNF, via quenching. Therefore, the chemical composition and the methods of CNF production affect subsequent studies. An in vitro triculture, small intestinal, epithelial model was used to assess the toxicity of ingested mDTEB labeled CNF. Zebrafish (Danio rerio) were used to assess in vivo environmental toxicity studies. No cytotoxicity was observed for CNF, or mDTEB labeled CNF, either in the triculture cells or in the zebrafish embryos.


Toxicity, fluorescence, nanomaterials, cellulose


Woodcock, J. , Patel, I. , Beams, R. , Stranick, S. , Gilman, J. , Fox, D. , Mulenos, M. , Sayes, C. , Salari, M. , Glen, D. , Demokritou, P. , Harper, B. , Stacey, H. , Kimberly, O. and Shatkin, J. (2021), Flourescently labeled cellulose nanofibers for environmental health and safety studies, Nanomaterials, [online], (Accessed April 14, 2024)
Created April 9, 2021, Updated March 10, 2023