PUB - Publikationen an der Universität Bielefeld

The toxicity of two iron-based nanoparticles: nFe3O4, and nZVI were assessed on freshwater microalgae, Chlamydomonas reinhardtii CC-5325. Microalgae response (total chlorophyll/carotenoids content, photosystem II efficiency, cell shape and total viable cell numbers) to the nanoparticles exposure (100 mg/L) was monitored up to 120 hours. Based on phytochrome and photosystem II analysis performed, almost no significant impact was found. However, microscopic analysis and the total viable cell numbers revealed a certain degree of inhibition effect showing altered cell shape, and higher number of dead cells after the exposure to both nanomaterials. The dead cell numbers increased within one hour after the exposure to nFe3O4, while nZVI caused rather slow inhibition effect and persisted until 48 h with the highest dead cell number. In a series of experiments performed, the results may justify that exposure of these two NPs initially slightly inhibited C. reinhardtii, however the culture was able to recover towards the end of the study, because of new cell generation and nZVI oxidation.