Laser-Induced Transferred Antibacterial Nanoparticles for Mixed-Species Bacteria Biofilm Inactivation

In the present study, copper and silver nanoparticles with a concentration of 20 & mu;g/cm(2) were synthesized using the method of laser-induced forward transfer (LIFT). The antibacterial activity of the nanoparticles was tested against bacterial biofilms that are common in nature, formed by several types of microorganisms (mixed-species bacteria biofilms): Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. The Cu nanoparticles showed complete inhibition of the bacteria biofilms used. In the course of the work, a high level of antibacterial activity was demonstrated by nanoparticles. This activity manifested in the complete suppression of the daily biofilm, with the number of bacteria decreasing by 5-8 orders of magnitude from the initial concentration. To confirm antibacterial activity, and determine reductions in cell viability, the Live/Dead Bacterial Viability Kit was used. FTIR spectroscopy revealed that after Cu NP treatment, there was in a slight shift in the region, which corresponded to fatty acids, indicating a decrease in the relative motional freedom of molecules.

Automated summary

In this study, copper and silver nanoparticles were synthesized with a concentration of 20 μg/cm² using laser-induced forward transfer (LIFT) method. The nanoparticles showed antibacterial activity against bacterial biofilms formed by mixed-species bacteria, including Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. The Cu nanoparticles completely inhibited the formation of biofilms, reducing the bacteria concentration by 5-8 orders of magnitude. The antibacterial activity was confirmed using the Live/Dead Bacterial Viability Kit, and FTIR spectroscopy revealed changes in fatty acids after Cu NP treatment.