MANGANESE SALEN COMPLEX IMOVILIZED BY ELECTROSTATIC INTERACTIONS WITH NAFION AND ITS APLICATION AS A SENSOR TOWARDS PEROXYNITRITE ANION.

The peroxynitrite anion (PON) is a strong oxidant produced in biological systems from superoxide anion (O2·-) and nitric oxide (·NO) [1]. The former is formed continuously in processes like cellular breath [2] and the later is an intra and intercellular chemical messenger involved in phisiological regulations [3]. The PON is formed in vitro and in vivo when both precursors are together and it takes place in a series of molecular and subcellular processes that can determine cellular disfunction or cellular death [4]. The PON’s biological half life (pH 7.4) has been estimated to be in the order of 10 to 100 ms [5, 6], reason why its determination in biological systems is really difficult and it should be done by indirect measurements. The manganese in cationic and complexed forms has shown activity towards reactive oxygen species (ROS). Salen type mangenese complexes linked to ciclodextrines or antibiotics like bacitracine show activity of the superoxide dismutase type [7, 8]. For this reason the purpose of this work is the preparation of modified glassy carbon electrodes with MnSalen complex, which will be imovilized by electrostatic interactions with Nafion films, to be used as sensors towards PON in aqueos fase at pH 10.5 at which conditions syntetic samples of PON are stable. Due to the anionic Nafion’s nature, in aqueos fase, its electrostatic interaction with cationic molecules like the MnSalen complex is possible (figure 1)