title: Two-Dimensional Algal Collection and Assembly by Combining AC-Dielectrophoresis with Fluorescence Detection for Contaminant-Induced Oxidative Stress Sensing.
abstract: An alternative current (AC) dielectrophoretic lab-on-chip setup was evaluated as a rapid tool of capture and assembly of microalga Chlamydomonas reinhardtii in two-dimensional (2D) close-packed arrays. An electric field of 100 V·cm⁻¹, 100 Hz applied for 30 min was found optimal to collect and assemble the algae into single-layer structures of closely packed cells without inducing cellular oxidative stress. Combined with oxidative stress specific staining and fluorescence microscopy detection, the capability of using the 2D whole-cell assembly on-chip to follow the reactive oxygen species (ROS) production and oxidative stress during short-term exposure to several environmental contaminants, including mercury, methylmercury, copper, copper oxide nanoparticles (CuO-NPs), and diuron was explored. The results showed significant increase of the cellular ROS when C. reinhardtii was exposed to high concentrations of methylmercury, CuO-NPs, and 10⁻⁵ M Cu. Overall, this study demonstrates the potential of combining AC-dielectrophoretically assembled two-dimensional algal structures with cell metabolic analysis using fluorescence staining, as a rapid analytical tool for probing the effect of contaminants in highly impacted environment.
authors.affiliation: Environmental Biogeochemistry and Ecotoxicology, Institute F.-A. Forel, Earth and Environmental Science, Faculty of Sciences, University of Geneva, 10 route de Suisse, Versoix CH-1290, Switzerland. coralie.suscillon@unige.ch.
authors.forename: Coralie
authors.initials: C
authors.lastname: Siebman
authors.affiliation: Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695, USA. odvelev@ncsu.edu.
authors.forename: Orlin D
authors.initials: OD
authors.lastname: Velev
authors.affiliation: Environmental Biogeochemistry and Ecotoxicology, Institute F.-A. Forel, Earth and Environmental Science, Faculty of Sciences, University of Geneva, 10 route de Suisse, Versoix CH-1290, Switzerland. vera.slaveykova@unige.ch.
authors.forename: Vera I
authors.initials: VI
authors.lastname: Slaveykova
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D016825:Chlamydomonas reinhardtii / Q000187:drug effects / Q000502:physiology*; D003300:Copper / Q000633:toxicity; D004586:Electrophoresis; D056656:Lab-On-A-Chip Devices / Q000382:microbiology*; D053768:Metal Nanoparticles / Q000633:toxicity; D008767:Methylmercury Compounds / Q000633:toxicity; D008856:Microscopy, Fluorescence; D018384:Oxidative Stress; D017382:Reactive Oxygen Species / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D008767:Methylmercury Compounds; D017382:Reactive Oxygen Species; D014874:Water Pollutants, Chemical; D003300:Copper; C030973:cupric oxide
keywords: Chlamydomonas reinhardtii; contamination; dielectrophoresis; fluorescence; reactive oxygen species; whole cell assembly