Abstract:Purpose: The purpose of this study was to assess the antibiofilm activity of silver nanoparticles (AgNPs) against multidrug resistant gram negative bacterial isolates. Different approaches have been used for preventing biofilm-related infections in health care settings. Many of these methods have their own difficulty, which include chemical-based complications; emergent antibiotic resistant strains, etc. Therefore, the aim of present study was to demonstrate the anti-biofilm activity of silver nanoparticles against the selected five strong biofilm forming multidrug resistant gram negative bacterial strains includes {Escherichia coli (ETEC12), Klebsiella pneumoniae (SKP7), Pseudomonas aeruginosa (ETPS11), Proteus mirabilis (PPM8) and Acinetobacter baumannii (SAB5)} were used in this study.
Methods: The anti-biofilm activity of AgNPs with different concentration of 12.5 to 100 μg/ml was investigated by direct visualisation applying test tube method and congo red agar method along with scanning electron microscopy (SEM) techniques.
Results: The biofilm inhibitory concentration was found to be in the range of 12.5 – 100 μg/ml. The technique using SEM provides the visual evidence that AgNPs arrested the bacterial growth and prevent the exopolysaccharides formation. The AgNPs effectively restricted biofilm formation of the tested bacteria. In our study, we could expose the complete anti-biofilm activity of AgNPs at a concentration as low as 100 μg/ml.
Conclusions: Our findings suggested that AgNPs can be defeated towards the development of potential anti-bacterial coatings for various biomedical and environmental applications. In future, the AgNPs may play major role in the coating of medical devices and treatment of infections caused due to extensively antibiotic resistant biofilm.