Iranian researchers at Islamic Azad University, Fars Science and Research Branch, produced antimicrobial cloths by discovering new microorganisms that are able to produce gold and silver nanoparticles. Nanoparticles produced through this method can be used in medicine, drug delivery, cloths, and bandages. Nowadays, nanoparticles produced through biological method, which is known as green technology, have many applications in various industries due to their reasonable price and also the fact that they don\'t produce toxic materials in the environment or on the surface of nanoparticles. Among the important applications of nanoparticles produced by microorganisms, mention can be made of medical industries, where the nanoparticles can be used in wound bandages and also in the production of devices used inside the body. The research provides the microorganisms with a good atmosphere to produce metallic nanoparticles. Briefly speaking, each of the microorganisms was exposed to metallic ions after the separation, and the nanoparticles were produced by the microorganisms through in-cellular method when the required temperature and other conditions were met. In addition to investigating new microorganisms able to produce silver and gold nanoparticles, this research also studied the antibacterial activity of nanoparticles considering the colors and shapes produced by them. Nanoparticles produced through this method can be used in water and wastewater purification filters as well as in medical industries and drug delivery. Results of the research have been published in details in February 2013 in BioMetals, vol. 26, issue 1, pp. 189-196.