Chlamydomonas reinhardtii displays aversive swimming response to silver nanoparticles. Issue 6 (4th May 2017)

• Record Type: Journal Article
• Authors: Mitzel, Michael R.; Lin, Nicholas; Whalen, Joann K.; Tufenkji, Nathalie
• Is Part Of: Environmental science. Volume 4:Issue 6(2017)
• Page Start: 1328
• Page End: 1338
• Publication Date: 2017-05-04
• Subjects: Environmental sciences -- Periodicals; Nanotechnology -- Periodicals; 620.505
• DOI: 10.1039/c7en00233e
• Languages: English
• ISSNs: 2051-8153

Abstract

Abstract : A microfluidic device was used to examine the avoidance response of a freshwater algae to engineered nanoparticles. Abstract : Engineered nanoparticles (ENPs) present in the environment are a potential risk to soil health, water safety and human health. Physical responses of microorganisms, such as avoidance behavior, could be an early indicator of biological outcomes upon exposure to ENP contamination. Chlamydomonas reinhardtii was exposed to gradients of nano-sized silver ( n Ag; 50 nm), gold ( n Au; 50 nm) and sulfated polystyrene latex ( n SPL; 22 nm) in a microfluidics device. Videos captured at targeted locations using enhanced darkfield microscopy showed that C. reinhardtii moved away from areas containing n Ag at and above 6 × 10 8 particles per mL. C. reinhardtii also avoided n SPL at and above 3 × 10 10 particles per mL, but did not avoid n Au at 6 × 10 8 or 6 × 10 9 particles per mL. Dissolution of Ag + around n Ag particles may elicit avoidance behavior, based on the response of C. reinhardtii to a gradient of Ag + (at ≤1 μM). We conclude that C. reinhardtii detect and respond to toxicants, but they do not sense nanomaterials directly, given their inconsistent response to similar concentrations of n Ag, n SPL and n Au. Rather, we postulate that their greater sensitivity to n Ag than other ENPs is due to toxicity resulting from dissolved Ag + around colloidal n Ag particles.