Silver has a long and intriguing history as an antibacterial agent. Antimicrobial behavior of silver or its bioactive compounds is directly proportional to Ag+ ion release and its availability to interact with bacterial or fungal cell membranes. Silver metal and its mineral compounds are ionized in the presence of water or body fluids. The silver ion is biologically active and readily interacts with proteins, amino acid residues, free anions and receptors on mammalian and eukaryotic cell membranes. Silver exhibits low toxicity in the human body, and minimal risk is expected by inhalation, ingestion، dermal application. However, continuous contact with silver can cause skin and eye problems. Reducing the particle size of silver (Ag nanoparticles in colloid) is also likely to enhance the release of silver due to increased exposed surface area. Silver colloid has nanoparticles (size below 100 nm) made of silver dispersed into water as the medium of suspension. It has brown color which is the same as silver colloids having sub-100 nm nanoparticles.
Dark brown color
Concentration of 1150 ppm
Large amount of metallic silver (99% metallic silver and 1% silver ions)
Size below 100 nanometers
The ability to destroy a variety of bacteria
Higher bactericidal ability due to nanometric size and also further amount of release of silver ions