The rapid spread of drug-resistant bacterial infections is driving a renewed search for new antibiotics, and concomitant efforts in modifying existing commercially available drugs to repurpose them. The latter strategy can save time and cost compared to the design and development of a completely new drug. We have investigated the complexation of antibiotics with metal ions as a potential alternative to enhance their antimicrobial effectiveness and overcome issues with multi-drug resistance (MDR).
Metal ions such as Zn(II), Cu(II), Ag(I) or silver nanoparticles are known for their antimicrobial properties and for their ability to increase the activity of different antibiotics. Coordination of drugs with certain transition metals is known to influence the drugs’ antimicrobial properties and biological activity. Isothermal titration calorimetry was used to examine the structure and interactions between metal ions and antibiotics. The metal complexes were also tested for antimicrobial activity showing a synergistic improvement in the activity of antibiotics.
At the current stage, our results add to the preliminary evidence supporting the application of silver ions as an antibiotic adjuvant to develop more efficient and sophisticated therapies and to offer a potential new approach towards treating the threat of ‘superbugs’.