title: A study on the cytotoxicity of carbon-based materials.
abstract: With an aim to understand the origin and key contributing factors towards carbon-induced cytotoxicity, we have studied five different carbon samples with diverse surface area, pore width, shape and size, conductivity and surface functionality. All the carbon materials were characterized with surface area and pore size distribution, X-ray photoelectron spectroscopy (XPS) and electron microscopic imaging. We performed cytotoxicity study in Caco-2 cells by colorimetric assay, oxidative stress analysis by reactive oxygen species (ROS) detection, cellular metabolic activity measurement by adenosine triphosphate (ATP) depletion and visualization of cellular internalization by TEM imaging. The carbon materials demonstrated a varying degree of cytotoxicity in contact with Caco-2 cells. The lowest cell survival rate was observed for nanographene, which possessed the minimal size amongst all the carbon samples under this study. None of the carbons induced oxidative stress to the cells as indicated by the ROS generation results. Cellular metabolic activity study revealed that the carbon materials caused ATP depletion in cells and nanographene caused the highest depletion. Visual observation by TEM imaging indicated the cellular internalization of nanographene. This study confirmed that the size is the key cause of carbon-induced cytotoxicity and it is probably caused by the ATP depletion within the cell.
authors: Department of Chemical Engineering, Widener University One University Place, Chester, PA 19013, USA. Electronic address: dsaha@mail.widener.edu.
authors: Dipendu
authors: D
authors: Saha
authors: Department of Chemical Engineering, Michigan Technological University, 1400 Townsend Dr., Houghton, MI 49931, USA.
authors: Caryn L
authors: CL
authors: Heldt
authors: Department of Chemical Engineering, Michigan Technological University, 1400 Townsend Dr., Houghton, MI 49931, USA.
authors: Maria F
authors: MF
authors: Gencoglu
authors: Department of Chemical Engineering, Michigan Technological University, 1400 Townsend Dr., Houghton, MI 49931, USA.
authors: K Saagar
authors: KS
authors: Vijayaragavan
authors: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
authors: Jihua
authors: J
authors: Chen
authors: Department of Chemical Engineering, Michigan Technological University, 1400 Townsend Dr., Houghton, MI 49931, USA.
authors: Ashish
authors: A
authors: Saksule
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism*; D018938:Caco-2 Cells; D002470:Cell Survival / Q000187:drug effects; D006108:Graphite / Q000737:chemistry / Q000493:pharmacokinetics / Q000633:toxicity; D006801:Humans; D053758:Nanoparticles / Q000737:chemistry / Q000633:toxicity; D017382:Reactive Oxygen Species / Q000378:metabolism*
chemical_list: D017382:Reactive Oxygen Species; D006108:Graphite; D000255:Adenosine Triphosphate
keywords: ATP depletion; Carbon materials; Cytotoxicity; Reactive oxygen species (ROS)