Bathophenanthroline-iron chelate

Among several iron chelators used, only o-phenanthroline inhibited the soluble dehydrogenase (42). It was shown by Hateff et al. (42) that incubation of the enzyme with o-phenanthroline results in the loss of labile sulfide, while pretreatment with bathophenanthroline sulfonate, Tiron (1,2-dihydroxybenzene 3,5-disulfonate) or ethylenediamine tetraacetate protects the enzyme against the loss of labile sulfide and inhibition of activity upon subsequent incubation with o-phenanthroline. The unique destructive ability of o-phenanthroline has been demonstrated by these investigators for several iron-sulfur proteins (S5,96). 

The production of hydroxyl radicals by tetra-chlorohydroquinone, a major metabolite of the widely used biocide pentachlorophenol in the presence of H2O2 was markedly inhibited by hydroxyl radical scavenging agents dimethyl sidphoxide and ethanol, as well as by tetrachlorohydroquinone radical scavengers desferrioxamine and other hy-droxamic acids (Zhu et al. 2000). In contrast, their production was not affected by the nonhydroxym-ate iron chelators, diethylenetriaminepentaacetic acid, bathophenanthroline disulphonic acid, and phytic acid, as well as the copper-specific chelator bathocuprione disulphonic acid. 

Radioisotope dilution using the chelating agent bathophenanthroline has been used to determine down to 5 xg/l iron in seawater [357]. 

The removal of metals from sensitive sites by chelation can serve to suppress HO degradation of tissue. Whereas EDTA reacts with 02 and H20273, both diethylene-triaminepentaacetic add (DTPA) and bathophenanthroline induce a diminuition in iron-dependent production of HO however DFOA has proved to be the most effective76. (The structure of DFOA is given in Sect. 3.3.2.)... 

As described in Section 3, iron can promote peroxidation of biological macromolecules due to its reactions with ROS and, thus, is of high toxic potential for cells, if it is not kept in a toxicologi-cally inactivated form bound to specific proteins. Only when iron is tightly bound to a chelator is its capacity for promoting LPO minimal. Amongst synthetic chelators of iron, fois-(2-aminoethyl)-amine-A, N,A, N -penta-acetic acid, desferrioxamine, o-phenanthroline and bathophenanthroline are able to complex Fe + and, thus, slow down reduction of Fe to Fe + by reductants like ascorbic acid or (O2) in vitro, but EDTA is ineffective. Desferrioxamine was originally developed for the treatment of iron overload disease because it binds Fe +... 

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