Interaction of copper and zinc ligands produced by Cylindrospermopsis raciborskii by determining the thermodynamic stability constant

• Grant number: 10/11985-0
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: March 01, 2013
• End date: February 28, 2015
• Field of knowledge: Biological Sciences - Ecology
• Principal Investigator: Ana Teresa Lombardi
• Grantee: Alessandra Emanuele Tonietto
• Host Institution: Centro de Ciências Biológicas e da Saúde (CCBS). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

The speciation of copper and zinc in natural waters is dominated by organic ligands present in the dissolved fraction, consequently, affecting the availability of trace metals to aquatic organisms. Microalgae excrete dissolved organic matter with a known ability to complex metals. Several studies determine the characteristics of complexation, conditional stability constant (K') and concentration of available ligands (CL), but few access the thermodynamic stability constant of complexes formed. This proposal aims at determining the thermodynamic stability constant (K) of Cu and Zn complexes formed with excreted organic compounds produced by Cylindrospermopsis raciborskii. The results that will be obtained here may provide support for toxicity studies seeking for external detoxification mechanisms by which microalgae may regulate the concentration of metals in its surrounding. Knowledge of the stability constant of metal - organic complexes furnishes chemical information that assists in distinguishing between different classes of ligands. Moreover, studies that evaluate the ability of algal excreted organic materials in relation to trace metals complexation have much interest in pure and applied research.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

TONIETTO, ALESSANDRA EMANUELE; OLIVEIRA, NATALIA L.; LOMBARDI, ANA TERESA; POLPO, ADRIANO. Copper and cadmium complexation by Cylindrospermopsis raciborskii exudates. WATER SCIENCE AND TECHNOLOGY, v. 73, n. 10, p. 2544-2551, MAY 2016. (10/11985-0)