Jaber Hemmati - Department of Microbiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
Mohsen Chiani - Department of NanoBiotechnology, Pasteur Institute of Iran, Tehran, Iran
Babak Asghari - Department of Microbiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
Ghodratollah Roshanaei - Department of Biostatistics, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran
Sara Soleimani Asl - Anatomy Department, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
Morvarid Shafiei - Department of Bacteriology, Pasteur Institute of Iran, Tehran, Iran
Mohammad Arabestani - Department of Microbiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran

Objective(s): Our study aimed to formulate a niosomal system for enhancing tannic acid’s antibacterial and antibiofilm activities against vancomycin-intermediate staphylococcus aureus (VISA). Materials and Methods: Niosomal tannic acid was formulated by the thin-film hydration technique, which their physicochemical attributes, including drug loading, particle size, zeta potential, morphology, encapsulation efficiency (EE%), polydispersity index (PDI), release profile, were evaluated. To investigate the cell viability of the prepared niosomes, the cytotoxicity effect was analyzed against the human foreskin fibroblast (HFF) cell line. Finally, the antibacterial and anti-biofilm activities of niosomal formulation were examined against VISA strains and compared tothe free drug.Results: Scanning electron microscopy images showed that the niosomal formulation incorporated tannic acid was homogeneous, spherical, and identical in size (۱۵۱.۹ nm). EE% and surface charge of the synthesized niosomes were ۶۸.۹۰% and -۶۰ mV, respectively. The tannic acid-encapsulated niosomes showed a significant antibacterial potential in comparison with the free drug. Furthermore, niosomal tannic acid reduced the biofilm formation ability in all VISA strains and efficiently eradicated the formed bacterial biofilms at the same concentrations of the free drug.Conclusion: Niosomes, as vesicular-based nanoparticles, are known to be potent drug delivery vehicles due to numerous features such as non-toxicity, small size, sustained-release profile, and protection from pharmaceutical degradation. Niosomes have a high capacity to deliver wide range of antimicrobial agents, including natural compounds, which could be presented as a novel approach against bacterial infections, particularly VISA strains.Objective(s): Our study aimed to formulate a niosomal system for enhancing tannic acid’s antibacterial and antibiofilm activities against vancomycin-intermediate staphylococcus aureus (VISA). Materials and Methods: Niosomal tannic acid was formulated by the thin-film hydration technique, which their physicochemical attributes, including drug loading, particle size, zeta potential, morphology, encapsulation efficiency (EE%), polydispersity index (PDI), release profile, were evaluated. To investigate the cell viability of the prepared niosomes, the cytotoxicity effect was analyzed against the human foreskin fibroblast (HFF) cell line. Finally, the antibacterial and anti-biofilm activities of niosomal formulation were examined against VISA strains and compared tothe free drug.Results: Scanning electron microscopy images showed that the niosomal formulation incorporated tannic acid was homogeneous, spherical, and identical in size (۱۵۱.۹ nm). EE% and surface charge of the synthesized niosomes were ۶۸.۹۰% and -۶۰ mV, respectively. The tannic acid-encapsulated niosomes showed a significant antibacterial potential in comparison with the free drug. Furthermore, niosomal tannic acid reduced the biofilm formation ability in all VISA strains and efficiently eradicated the formed bacterial biofilms at the same concentrations of the free drug.Conclusion: Niosomes, as vesicular-based nanoparticles, are known to be potent drug delivery vehicles due to numerous features such as non-toxicity, small size, sustained-release profile, and protection from pharmaceutical degradation. Niosomes have a high capacity to deliver wide range of antimicrobial agents, including natural compounds, which could be presented as a novel approach against bacterial infections, particularly VISA strains.

Biofilm, Drug Delivery, Niosome, tannic acid, Vancomycin-intermediate Staphylococcus aureus (VISA)