Chapter 80: Silver

INTRODUCTION

SOURCE

Silver is a naturally occurring chemical element on our planet (with the chemical symbol Ag). It is obtained by mining. Nanoparticles are produced in the laboratory and are designed to be a particular size and shape. Silver salts are formed by combining silver with other agents. This can occur spontaneously or in the laboratory setting.

HISTORY

The medicinal use of silver dates back at least to the time of ancient Greek historian Herodotus, who lived in the 5th century BCE and stated that when the King of Persia went to war, he would take boiled water stored in flagons of silver to treat wounds.^1,2 But the awareness of metallic silver dates back further to 4,000 BCE.² The Phoenicians were known to store water and other liquids in silver vats to prevent them from spoiling. Although the metallic silver in the vats was not soluble in water and therefore would not have antimicrobial properties, the beneficial properties noted by the Romans and Phoenicians can be explained by the fact that leeching of silver ions into water occurred when the water was stored for long periods of time.³ Silver nitrate was cited in a Roman pharmacopeia published in 69 BCE (Table 80-1).² Over three hundred years earlier, Hippocrates, the father of medicine, documented the beneficial healing and disease-modifying properties of silver.⁴ Avicenna is reported to have used silver as a blood purifier circa 980 CE and Paracelsus used silver systemically, and topically applied silver nitrate to wounds in the early 1500s, a practice that has continued into modern times.²

In 1869, Raulin observed that the fungus Aspergillus niger could not grow in silver vessels.⁵ The Swiss botanist von Nägeli was studying silver when he devised the term “oligodynamic” to describe any metal that exhibits bactericidal properties at minute concentrations (oligos, small ...