Structure-Activity Relationship of Anionic and Cationic Polyamidoamine (PAMAM) Dendrimers against Staphylococcus aureus

ABSTRACT

Dendrimers are potent synergists, carriers, and delivery molecules for natural biological products and pharmaceuticals. Staphylococcus aureus (S. aureus) infection is causing serious diseases in humans and animals. Given the recorded antibacterial and antiviral activity of terminal-charged PAMAM dendrimers, the relation between dendrimer charge type and generation is to be established against S. aureus. Three types of polyanionic dendrimers comprising terminal groups sodium carboxylate (generations 1.5, 2.5, 3.5, and 4.5), hydroxyl (generations 2, 3, 4, and 5), and succinamic acid (generations 2, 3, 4, and 5) and polycationic dendrimers containing primary amine (generations 2, 3, 4, and 5) were in antibacterial assays to determine their zone of inhibition and antibacterial activity. Cationic dendrimers were more potent than anionic dendrimers. The largest inhibition was shown by G(5)-128NH2 followed by G(4)-64NH2 primary amine dendrimers. Carboxylate, hydroxyl, and succinamic acid dendrimers showed weaker effects. Owing to their antibacterial actions, the addition of dendrimers to antibiotic preparations may increase their efficacy by their intrinsic and bacterial action by damaging the bacterial membranes as well as their usage in drug delivery.