Toxicity antimony ions

Werner s studies led to a general realization that the typical properties of metal ions could be modified by binding them firmly to appropriate chelating agents, and it was a short step to extend these ideas to the biological properties of toxic metal ions. An early application of this in medicine was the use of the J-tartrate complex of antimony(III) in the treatment of parasitic diseases such as schistosomiasis 2. The parasite which causes this disease is readily poisoned by antimony(III) compounds, but for simple antimony compounds the margin of safety is too small and humans suffer from cardiotoxicity when such compounds are administered. The J-tartrate complex allows this to be somewhat more readily controlled and allows the more... 

The tartrate complex of antimony(III), tartar emetic, K2[Sb2(J-C406H2)2]-3H20, has been known in medicine for over 300 years and is used for treatment of schistosomiasis and leishmaniasis the toxic side effects can be mediated by penicillamine. In the salts the ion has a binuclear structure [Fig. 10-9(b)] and the Sb atom... 

This test identifies the substance to be examined as a salt of antimony(III), Sb +, or antimony(V), Sb +. Antimony(III) and antimony(V) were formerly used in the oral treatment of intestinal worms and topically in the treatment of infections of protozoan parasites in the skin. But since especially tetrava-lent antimony is poisonous, they have generally been replaced by less toxic alternatives. At present, there are no monographs of antimony compounds in the European Pharmacopoeia. Antimony forms both tetra- and pentavalent ions, but the pentavalent is mainly found in oxides containing the antimonate ion, Sb04. Antimony(III), on the other hand, can be found as the free dissociated ion, Sb +, but, as also for example bismuth, since it reacts with water at neutral pH, forming antimonate. 

The toxicity of some metals depends on both their oxidation state and the rapidity with which the metal ion can undergo oxidation and reduction. Some compounds of metals such as arsenic and antimony are more toxic in their lower oxidation state than the higher oxidation state. This feature can be explained by the tendency of these compounds to become more stable in higher valence states, disrupting cellular processes. The possibility of transition elements to exist in several oxidation states is an attribute that makes them particularly suitable for biological functions, but simultaneously redox changes in vivo can have a strong influence on overall metal toxicity (Hoeschele et al. 1991). 

In this chapter we have defined the key factors for the development of receptors as indicator dyes , and surface-confined nanomaterials as carriers , for the creation of optical chemical sensors capable of selectively discriminating trace levels of toxic analytes. Our aim was to widen the knowledge base with regards to the causes of- and solutions to - metal-ion toxicity. A key factor when designing optical nanosensors to sense mercury, cadmium, lead and antimony is the stable immo-... 

While some cathodic poisons such as sulfides and selenides are adsorbed on the metal surface, compounds of arsenic, bismuth, and antimony are reduced at the cathode to deposit a layer of the respective metals. Sulfides and selenides generally are not useful inhibitors because they are not very soluble in acidic solutions, they precipitate many metal ions, and they are toxic. Arsenates are used to inhibit corrosion in strong acids, but in recent years the trend has been to rely more on organic inhibitors because of the toxicity of arsenic. 

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