Dados do Trabalho

Título

ANTIBACTERIAL AND ANTIBIOFILM ACTIVITY OF SILVER NANOPARTICLES AGAINST RESISTANT Pseudomonas aeruginosa STRAINS

Introdução

Pseudomonas aeruginosa is an opportunistic pathogen responsible for causing severe infections, especially in immunocompromised individuals, being associated with Healthcare-Associated Infections. It is noteworthy that multidrug-resistant strains promote therapeutic failure, making the treatment of P. aeruginosa infections a challenge for global public health. In addition to resistance, biofilm formation by P. aeruginosa is a virulence factor that enables the persistence of infections and colonization in biotic and abiotic environments. Therefore, treatment with silver nanoparticles (AgNPs) appears as a promising alternative for the development of therapeutic strategies against resistant and biofilm-producing strains of P. aeruginosa. 

Objetivo (s)

Thus, the objective of this work was to evaluate the antibacterial and antibiofilm activity of silver nitrate (AgNO3) and silver nanoparticles (AgNPs) in clinical isolates of antimicrobial-resistant Pseudomonas aeruginosa.

Material e Métodos

The determination of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of AgNO3 and AgNP against PA18, PA19, PA69 and PA78 strains was performed by the broth microdilution method according to the Clinical and Laboratory Standards Institute. The determination of the minimum biofilm inhibitory concentration (MBIC) and minimum biofilm eradication concentration (MBEC) of AgNO3 and AgNP against  PA18, PA19, PA69 and PA78 strains was performed by the crystal violet method.

Resultados e Conclusão

The MIC and MBC obtained for AgNO3 against resistant strains of P. aeruginosa ranged from 25µg/ml to 12.5µg/ml, while AgNPs presented MIC and MBC values of 50µg/ml for all strains tested. CIMB and CEMB values for AgNO3 ranged from >25µg/ml to 12.5µg/ml, and >200µg/ml to 6.25µg/ml, respectively. While the CIMB and CEMB for AgNPs ranged from 1.56µg/ml to 12.5µg/ml, and 12.5µg/ml to 100µg/ml, respectively. This study demonstrates the antibacterial and antibiofilm potential of AgNP, highlighting the effectiveness of these nanostructures for inhibiting and eradicating biofilm when compared to AgNO3. Thus, AgNP present themselves as a promising future therapeutic strategy for the treatment of infections caused by resistant and biofilm-producing strains of P. aeruginosa.

Palavras Chave

bacterial resistance; biofilm; Gram-negative bacteria; nanostructures.