Int. J. Mol. Sci. 2013, 14(7), 14395-14407; doi:10.3390/ijms140714395
Synergistic Effects of Nano-Sized Titanium Dioxide and Zinc on the Photosynthetic Capacity and Survival of Anabaena sp.
State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science & Engineering, Tongji University, Shanghai 200092, China
*
Author to whom correspondence should be addressed.
Received: 1 April 2013 / Revised: 24 June 2013 / Accepted: 24 June 2013 / Published: 11 July 2013
(This article belongs to the Special Issue Bioactive Nanoparticles 2013)
Abstract
Anabaena sp. was used to examine the toxicity of exposure to a nano-TiO2 suspension, Zn2+ solution, and mixtures of nano-TiO2 and Zn2+ suspensions. Typical chlorophyll fluorescence parameters, including effective quantum yield, photosynthetic efficiency and maximal electron transport rate, were measured by a pulse-amplitude modulated fluorometer. Nano-TiO2 particles exhibited no significant toxicity at concentrations lower than 10.0 mg/L. The 96 h concentration for the 50% maximal effect (EC50) of Zn2+ alone to Anabaena sp. was 0.38 ± 0.004 mg/L. The presence of nano-TiO2 at low concentrations (<1.0 mg/L) significantly enhanced the toxicity of Zn2+ and consequently reduced the EC50 value to 0.29 ± 0.003 mg/L. However, the toxicity of the Zn2+/TiO2 system decreased with increasing nano-TiO2 concentration because of the substantial adsorption of Zn2+ by nano-TiO2. The toxicity curve of the Zn2+/TiO2 system as a function of incremental nano-TiO2 concentrations was parabolic. The toxicity significantly increased at the initial stage, reached its maximum, and then decreased with increasing nano-TiO2 concentration. Hydrodynamic sizes, concentration of nano-TiO2 and Zn2+ loaded nano-TiO2 were the main parameters for synergistic toxicity. View Full-TextKeywords:
synergistic toxicity; zinc; nanoparticles; titanium dioxide; Anabaena sp.
▼
Figures
This is an open access article distributed under the Creative Commons Attribution License (CC BY 3.0).
Share & Cite This Article
MDPI and ACS Style
Tang, Y.; Li, S.; Qiao, J.; Wang, H.; Li, L. Synergistic Effects of Nano-Sized Titanium Dioxide and Zinc on the Photosynthetic Capacity and Survival of Anabaena sp.. Int. J. Mol. Sci. 2013, 14, 14395-14407.
Related Articles
Article Metrics
Comments
[Return to top]
Int. J. Mol. Sci.
EISSN 1422-0067
Published by MDPI AG, Basel, Switzerland
RSS
E-Mail Table of Contents Alert