The rise of antimicrobial resistance to antibiotics (AMR) as a healthcare crisis has led to a tremendous social and economic impact, whose damage poses a significant threat to future generations. Current treatments either are less effective or result in further acquired resistance. At the same time, several new antimicrobial discovery approaches are expensive, slow, and relatively poorly equipped for translation into the clinical world. Therefore, the use of nanomaterials is presented as a suitable solution. In particular, this review discusses selenium nanoparticles (SeNPs) as one of the most promising therapeutic agents based in the nanoscale to treat infections effectively. This work summarizes the latest advances in the synthesis of SeNPs and their progress as antimicrobial agents using traditional and biogenic approaches. While physiochemical methods produce consistent nanostructures, along with shortened processing procedures and potential for functionalization of designs, green or biogenic synthesis represents a quick, inexpensive, efficient, and eco-friendly approach with more promise for tunability and versatility. In the end, the clinical translation of SeNPs faces various obstacles, including uncertain in vivo safety profiles and mechanisms of action and unclear regulatory frameworks. Nonetheless, the promise possessed by these metalloid nanostructures, along with other nanoparticles in treating bacterial infections and slowing down the AMR crisis, are worth exploring.
