Antimicrobial seleno-organic coatings and compounds acting primarily on the plasma membrane: A review

Bacterial infections have been the major cause of disease throughout history. However, some bacteria have evolved to attain multi-drug resistance (MDR) against a wide range of antibiotics. Today, the acquisition and spread of antibiotic resistance among pathogenic bacteria constitute a major threat to modern medicine. One approach to overcoming MDR bacteria has been the use of elemental selenium to generate reactive oxygen species (ROS) which damage the cell membrane and intracellular proteins. In this review, we will discuss the underlying antibacterial mechanisms of selenium-coated devices, selenium conjugated peptides, antibodies, and nanoparticles against MDR bacteria. We conducted a literature review of the characteristics of selenium and recent developments of its utilization as an effective treatment strategy. One of the proposed solutions to this problem was the attachment of elemental selenium to different materials to kill bacteria through the catalytic generation of superoxide radicals. Superoxide anion, along with hydrogen peroxide and hydroxyl radical, are the noxious byproducts of partial oxygen reduction that perform lethal cellular oxidative damage. Due to the short half-life of the superoxide radical (≤1 milliseconds) only bacteria localized near selenium are destroyed. Therefore, due to this antimicrobial mechanism, surface coatings of a plethora of devices containing elemental selenium have been demonstrated as an effective method against pathogenic and antibiotic resistant bacteria. Furthermore, utilization of selenium conjugated peptides, antibodies, and nanoparticles have been investigated as both antimicrobial and anti-cancer therapeutics.