title: Assessment of cytocompatibility of surface-modified CdSe/ZnSe quantum dots for BALB/3T3 fibroblast cells.
abstract: With the widespread use of quantum dots (QDs), the likelihood of exposure to QDs has been assumed to have increased substantially. Recently, QDs have been employed in numerous biological and medical applications. However, there is a lack of toxicological data pertaining to QDs. In this study, we aimed to investigate the cytocompatibility of surface-modified CdSe/ZnSe QDs for BALB/3T3 fibroblast cells. The ligands used for surface modification are mercaptopropionic acid (MPA) and Gum arabic (GA)/tri-n-octylphosphine oxide (TOPO). Cells were exposed to different concentrations of QDs followed by illustrative cytotoxicity analyses. Furthermore, we used a confocal microscope to assess intracellular uptake of QDs. Confocal images showed that MPA-coated QDs were distributed inside the cytoplasmic region of cells. In contrast, GA/TOPO-coated QDs were not found inside cells. MPA-coated QDs were highly cytocompatible, whereas GA/TOPO-coated QDs were toxic to the cells. Cells treated with GA/TOPO-coated QDs showed altered morphology, decreased viability, significant concentrations of intracellular free cadmium, detectable reactive oxygen species (ROS) formation, depolymerized cytoskeleton, and irregular-shaped nuclei. This study suggests that surface modification by ligands plays a significant role in the prevention of cytotoxicity of QDs.
authors.affiliation: Department of Chemistry and Green Home Energy Technology Research Center, Kongju National University, Kongju 314-701, Republic of Korea.
authors.forename: Sanjeev Kumar
authors.initials: SK
authors.lastname: Mahto
authors.forename: Chansik
authors.initials: C
authors.lastname: Park
authors.forename: Tae Hyun
authors.initials: TH
authors.lastname: Yoon
authors.forename: Seog Woo
authors.initials: SW
authors.lastname: Rhee
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D041702:BALB 3T3 Cells; D002104:Cadmium / Q000737:chemistry / Q000378:metabolism / Q000633:toxicity; D002470:Cell Survival / Q000187:drug effects; D003603:Cytotoxins / Q000737:chemistry / Q000633:toxicity*; D051379:Mice; D009943:Organophosphorus Compounds / Q000737:chemistry; D045663:Quantum Dots; D017382:Reactive Oxygen Species / Q000378:metabolism; D012643:Selenium / Q000737:chemistry / Q000633:toxicity; D018675:Toxicity Tests; D015032:Zinc / Q000737:chemistry / Q000633:toxicity
chemical_list: D003603:Cytotoxins; D009943:Organophosphorus Compounds; D017382:Reactive Oxygen Species; D002104:Cadmium; C044965:trioctyl phosphine oxide; D012643:Selenium; D015032:Zinc