Silver has been used to fight infections and control spoilage because of its high toxicity to germs while relatively non-toxic to human cells. For example coating medical-device surfaces with anti-microbial silver particles of 2 to 20 nm size prevents biofilm formation. Nano silver coatings are used for a variety of other applications such as in kitchenware, kitchen appliances, tableware, personal care products, watch accessories, door handles, pet care products, public facilities, etc. Few precursor products are also available in different types of colloids composed of nanosilver-titanium-dioxide with an average particle size of 5nm. The actual size of the incorporated particle in antimicrobial coating is less than one nm. and the protectve coating lasts for anywhere upto 5 years.