title: Biological effects of agglomerated multi-walled carbon nanotubes.
abstract: The physicochemical properties of nanomaterials play crucial roles in determining their biological effects. Agglomeration of nanomaterials in various systems is a common phenomenon, however, how agglomeration affects the biological consequence of nanomaterials has not been well investigated because of its complexity. Herein, we prepared variable sized agglomerates of oxidized multi-walled carbon nanotubes (O-MWCNTs) by using Ca(2+) and studied their cellular uptake and cytotoxicity in HeLa cells. We found the altered property of O-MWCNTs agglomerates could be controlled and adjusted by the amount of Ca(2+). Agglomeration remarkably facilitated the cellular uptake of O-MWCNTs at the initial contact stage, due to the easy contact of agglomerates with cells. But agglomeration did not induce evident cytotoxicity when the concentration of O-MWCNTs was less than 150μg/mL. That was assayed by cell proliferation, membrane integrity, apoptosis and ROS generation. This study suggests us that the biological behaviors of nanomaterials could be altered by their states of agglomeration.
authors.affiliation: Institute of Nanochemistry and Nanobiology, Shanghai University, Shanghai 200444, China.
authors.forename: Zheng-Mei
authors.initials: ZM
authors.lastname: Song
authors.affiliation: Institute of Nanochemistry and Nanobiology, Shanghai University, Shanghai 200444, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Wang
authors.affiliation: Institute of Nanochemistry and Nanobiology, Shanghai University, Shanghai 200444, China.
authors.forename: Ni
authors.initials: N
authors.lastname: Chen
authors.affiliation: Institute of Nanochemistry and Nanobiology, Shanghai University, Shanghai 200444, China.
authors.forename: Aoneng
authors.initials: A
authors.lastname: Cao
authors.affiliation: Institute of Nanochemistry and Nanobiology, Shanghai University, Shanghai 200444, China; Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
authors.forename: Yuanfang
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Institute of Nanochemistry and Nanobiology, Shanghai University, Shanghai 200444, China. Electronic address: hwang@shu.edu.cn.
authors.forename: Haifang
authors.initials: H
authors.lastname: Wang
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D001692:Biological Transport; D002118:Calcium / Q000737:chemistry*; D002462:Cell Membrane / Q000737:chemistry / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects*; D002470:Cell Survival / Q000187:drug effects; D005427:Flocculation; D006367:HeLa Cells; D006801:Humans; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D017382:Reactive Oxygen Species / Q000819:agonists / Q000378:metabolism
chemical_list: D037742:Nanotubes, Carbon; D017382:Reactive Oxygen Species; D002118:Calcium
keywords: Agglomeration; Calcium ion; Multi-walled carbon nanotube; Toxicity; Uptake