Antibiofilm properties of chemically synthesized silver nanoparticles found against Pseudomonas aeruginosa

Abstract

Nanomedicine is now being introduced as a recent trend in the field of medicine. It has been documented that metal nanoparticles have antimicrobial effects for bacteria, fungi and viruses. Recent advances in technology has revived the use of silver nanoparticles in the medical field; treatment, diagnosis, monitoring and control of disease. It has been used since ancient times for treating wide range of illnesses. Bacterial cells adheres to surfaces and develop structures known as biofilms. These structures are natural survival strategy of the bacteria to invade the host. They are more tolerant to commonly used antimicrobial agents, thus being more difficult to be controlled. This leads to increase in severity of infection. In this study, we have investigated the effect of silver nanoparticles in the formation of biofilm in multidrug resistant strains of Pseudomonas aeruginosa. Observation showed that biofilm formation occurred at bacterial concentration of 106 cfu/ml for the sensitive strain of P. aeruginosa while in the resistant strain, the biofilm was evident at bacterial concentration of about 103 cfu/ml. The biofilm were then tested against various concentrations of silver nanoparticles to determine the inhibitory effect of the silver nanoparticles. In the sensitive strain, 20 μg/ml of silver nanoparticles inhibited the growth optimally at bacterial concentration of 104 cfu/ml with an inhibition rate of 67%. Similarly, silver nanoparticles inhibited the formation of biofilm in the resistant strain at an optimal bacterial concentration of 105 cfu/ml with an inhibition rate of 56%. Thus, silver nanoparticles could be used as a potential alternative therapy to reduce severity of disease due to P. aeruginosa infections.

Silver Nanoparticles as Potential Antibacterial Agents

“…Multidrug resistant (MDR) strains of P. aeruginosa were treated with AgNPs to investigate the eventual increased resistance compared to sensible strains. In the multidrug resistant strains, the inhibition rate of AgNPs was highest at concentration of 20 μg/mL similarly to the parental strain, therefore biofilms derived from multiresistant bacteria do no show an increased resistance to silver [69].…”

Silver Nanocomposite Biosynthesis: Antibacterial Activity against Multidrug-Resistant Strains of Pseudomonas aeruginosa and Acinetobacter baumannii

“…Palanisamy et al tested silver nanoparticles (2.5, 5, 10 and 20 µg/mL) against bacterial growth and reported that multidrug-resistant bacteria were more sensitive to AgNPs at 20 µg/mL [27]. Additionally Wilding et al reported that the oral administration of AgNPs at 1 mg/mL and 10 µL/g of body mass, in repeated doses during 28 days, do not cause a significant effect on the murine gut microbiome [7].…”

The effect of biologically and chemically synthesized silver nanoparticles (AgNPs) on biofilm formation

“…The penetration rate of the biofilm may also differ between strains. The ability of silver nanoparticles to agglomerate may also have meaning to their the activity [17]. Therefore, Nookola et al [19] demonstrated antibacterial and antifungal properties of chemical silver nanoparticles on environmental strains.…”

“…Nanoparticles have specific properties and chemical reactivity [6,17,19]. One of them is high surface area to volume.…”