Platinum-protein conjugates

NH4)2(PtCU), H2(PtCl6)] are responsible for this sensitivity. The bromide and iodide compounds are less effective. These platinum compounds form a platinum-protein conjugate that is the true allergen. Tetrachloroplatinates are mutagens. This seems to be true only of complex platinum salts. It does not apply to the complex salts of the other precious metals. Platinum amine nitrates and perchlorates either detonate when heated or are impact-sensitive. 

Little is known about the actual hapten-carrier linkages of the halide platinum salts except for their affinity for proteins in general and for sulphydryl bonds in particular. There is some limited evidence of sensitisation of rats by injection of platinum-protein conjugates (Khan et al. 1975). Such conjugates are not effective for skin prick tests and studies of platinum-human albumin conjugates have shown the presence of 26 platinum molecules for every 10" molecules of albumin. Under these conditions steric hindrance and paucity of available platinum-specific determinants are probably responsible for the poor eliciting capacity of such conjugates. 

Peptides and proteins have found tremendous use in tumor imaging and therapy when used as receptor-targeting moieties conjugated to radioactive metals. Likewise, a few groups have targeted platinum drugs to specific cancer cells... 

The direct electrochemical reduction and oxidation of bacteriorhodopsin, a bacterial photoreceptor protein, have recently been described. The redox site of this molecule is organic, being a conjugated double bond system and a Schiff base. As previously noted for other proteins, strong adsorption onto mercury is evident with bacteriorhodopsin. The adsorbed molecules undergo reduction-oxidation reactions near -0.8 V which appear to be polarographically reversible. An oxidation wave is observed at platinum at +0.80 V and has been ascribed to the chromophore. ... 

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