Electrochemical and Spectrometric Detection of Low-Molecular-Weight Organic Acids and their Complexes with Metals

The knowledge of thermodynamic balances among metal species in environmental matrixes can help in the understanding of processes related to the environmental stress of plants and in the design of suitable phytoremediation strategy. In these processes, lowmolecular- weight organic acids (LMWOAs) play a very important role, and therefore the determination of metals species with LMWOAs is of current research interest. Electrochemical techniques available for the trace analysis of metal ions are suitable for speciation studies including the computation of stability constants and the determination of the stoichiometries from the properties of voltammograms/ polarograms (pseudopolarograms). Additionally, labile and inert (stable) complexes can be distinguished by several electrochemical methods. A new approach is the hyphenation of electrochemistry (EC) with electrospray ionization mass spectrometry (ESI-MS), which provides assistance to the description of the electrochemical behavior of the complexes as far as both thermodynamic aspects and kinetic properties of metals complexes with LMWOAs are concerned.