Introduction: Bacterial infections still represent a serious and increasing therapeutic problem despite exponentially increasing knowledge in all fields of medicine and considerable improvements in both diagnostic and therapeutic medicine.
In the 21st century, nanotechnology has become one of the most important and influential technologies in science worldwide. Nanomaterials are structures that have at least one dimension on the nanometer scale (1-100 nanometers). an option to overcome biofilm formation and bacterial resistance is restoring the antibacterial effects of antibiotics by their combination with novel nanostructured antibacterial substances. The nanostructured antibacterial materials include metal or nonmetal nanoparticles (NPs) such as silver, gold, copper, bismuth, and selenium, and metal oxide NPs such as ZnO or Al2O3 NPs. Most of these nanostructured materials show antibacterial effects themselves through nonspecific activity, which can limit the development of bacterial resistance. one of the outstanding advantages of nanotechnology in antimicrobial treatment is the potential of this technology to deal with existing microbial resistance and also to prevent its further development. These results can be achieved by designing different strategies, including simultaneous targeting of multiple pathways using multiple antimicrobial nanomaterials. There are two main approaches in nanomedicine applications in antimicrobial therapies. The first approach is the expansion of organic and inorganic nanomaterials with antimicrobial properties and the second approach is the release of antimicrobial drugs with nanoparticles. this study focuses on the mechanisms of bacterial resistance and antibacterial activity of nanoparticles, because investigating the antibacterial mechanisms of these particles is very important for the production of more effective antimicrobial agents.
Methods: To select the used documents, first the titles found by the search engine were checked in terms of thematic relevance. The found materials were divided into three groups: internet, books, and articles. The search words were: "Bacteria,” “Nanotechnology,” “Antibacterial,” “Nano”, ”Narrative Review article(s) ” ،”Review article(s) ” review of the literature, narrative review, title, abstract, authorship, ethics, peer review, research methods, medical writing, scientific writing, using PubMed, Scopus, Science Direct, Google Scholar databases and Scientific Information Database. in addition, manual searches of other relevant journals and keywords searches were performed. We have focused on published papers from 2010 to 2021.
Results: Antibacterial effects of nanoparticles are created due to the presence of special physical and chemical properties in nanoparticles, because unlike common antibiotics, nanoparticles have specific dimensions of about 100 nm. Their small and unique size leads to the creation of new properties, among these properties is greater interaction with cells due to the creation of a larger surface, increasing the surface-to-mass ratio and controlling their acceptance. Nanoparticles have a high ability to be used as a carrier and adjuvant, and they also have the ability to strengthen the immune system and fight bacteria using several mechanisms at the same time. Nanoparticles attack microbes through multiple mechanisms that are active simultaneously. Simultaneous mechanisms greatly reduce the probability of multiple mutations in different genes, so it becomes very difficult to create resistance against nanoparticles. Nanoparticles can fight against microbes and the resistance mechanism in bacteria, they can also act as a carrier for antibiotics. Combining nanoparticles with antimicrobial substances, such as antibiotics, peptides or various biological molecules, is one It is one of the new and suitable methods to eliminate antibiotic resistance. The most important characteristics and advantages of nanoparticles as carriers of antibiotics are: small size of nanoparticles, protection of nanoparticles from drugs, accuracy in drug targeting, ability to control drug release, and the ability to combine and transport several antibacterial drugs.
Conclusion: Today, antibiotic resistance in bacteria is the most important crisis in global public health, and new research should be done worldwide for the development of more effective antimicrobial compounds. Nanoparticles are among the agents that have been given much attention to target bacteria as an alternative to antibiotics, so that they are beneficial in the treatment of bacterial infections. According to the studies, nanoparticles have a high potential to solve the problem of the emergence of resistant bacteria; Because nanoparticles either do not have cytotoxicity or usually their toxicity is very low and their production methods do not include risky and complex processes.