This article, published in the *International Journal of Nanomedicine* on June 5, 2012, reviews the antimicrobial applications of nanotechnology, focusing on the development of novel methods to combat bacterial infections and the growing resistance to conventional antibiotics. The article highlights the unique bactericidal mechanisms of nanoparticles, which differ from traditional antibiotics, and discusses various techniques for evaluating their effectiveness. Key points include: - The increasing need for new antibiotics due to the rise of antibiotic-resistant bacteria, such as *Staphylococcus aureus* (MRSA). - The effectiveness of nanoparticles in reducing bacterial activity, with their small size enhancing surface-to-volume ratio and interaction with bacteria. - Various techniques for assessing bacterial viability, including optical density measurements, cell counting instruments, spread-plate colony counts, crystal violet staining, live/dead staining, and tetrazolium salt reduction assays. - The antibacterial properties of specific nanoparticles, such as zinc oxide (ZnO), silver, copper, and iron oxide, and their mechanisms of action. - The importance of particle size, shape, chemistry, and zeta potential in determining the antibacterial activity of nanoparticles. - The potential cytotoxicity of nanoparticles to eukaryotic cells, emphasizing the need for localized treatment to minimize off-target effects. - The promise of antibacterial nanorough surfaces in enhancing the effectiveness of nanoparticles. The article concludes by emphasizing the potential of nanotechnology in developing novel antimicrobial agents and the need for further research to optimize their use in medical applications.This article, published in the *International Journal of Nanomedicine* on June 5, 2012, reviews the antimicrobial applications of nanotechnology, focusing on the development of novel methods to combat bacterial infections and the growing resistance to conventional antibiotics. The article highlights the unique bactericidal mechanisms of nanoparticles, which differ from traditional antibiotics, and discusses various techniques for evaluating their effectiveness. Key points include: - The increasing need for new antibiotics due to the rise of antibiotic-resistant bacteria, such as *Staphylococcus aureus* (MRSA). - The effectiveness of nanoparticles in reducing bacterial activity, with their small size enhancing surface-to-volume ratio and interaction with bacteria. - Various techniques for assessing bacterial viability, including optical density measurements, cell counting instruments, spread-plate colony counts, crystal violet staining, live/dead staining, and tetrazolium salt reduction assays. - The antibacterial properties of specific nanoparticles, such as zinc oxide (ZnO), silver, copper, and iron oxide, and their mechanisms of action. - The importance of particle size, shape, chemistry, and zeta potential in determining the antibacterial activity of nanoparticles. - The potential cytotoxicity of nanoparticles to eukaryotic cells, emphasizing the need for localized treatment to minimize off-target effects. - The promise of antibacterial nanorough surfaces in enhancing the effectiveness of nanoparticles. The article concludes by emphasizing the potential of nanotechnology in developing novel antimicrobial agents and the need for further research to optimize their use in medical applications.