Silver biological function

Silver is one of the earliest known metals. Silver has no known physiologic of biologic function, though colloidal silver is widely sold in health food stores. 

Antibiotics form a large proportion of the remaining natural products which have been examined by X-t y analysis. The crystallographic interest in antibiotics centres both on the ability to form a variety of complexes with different metal ions, and also on the polarization of hydrophobic and hydrophilic properties within the moiecuies, since it has been suggested that both these features may be implicated in the biological functions of such molecules. One antibiotic, monensin (158), has been studied both as the free acid, and also as the silver(i) salt. In the metal complex, the... 

Although many individual biomolecular functions have already been studied by labeling bioactive molecules, proteins, antibodies and DNA strands with organic dyes and quantum dots, the extraordinary properties of silver clusters suggest that these species might be competitive alternatives (Table 1 and Fig. 11a). Nevertheless, silver clusters present some disadvantages in their application to biological systems. 

Joerger, R., Klaus, T., and Granqvist, C.G. 2000. Biologically produced silver-carbon composite materials for optically functional thin film coatings. Advanced Materials, 12 407-9. 

Silver A (1974) Do cholinersterase have a function other than in transmission In The Biology of Cholinesterase. North-Holland, Amsterdam, 355-388. 

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