Abstract
Background: T Microorganisms cause many diseases for the human body such as urinary tract infection and, therefore, it is highly important to eliminate and control them. Bacterial resistance to different types of antibiotics was increased and it is necessary to find alternative agents to eliminate these microbes.
Methods: This study aimed was to evaluate the antimicrobial effect of different concentrations of titanium dioxide nanoparticles (TiO2 NPs) on some gram-positive bactria, gram-negative bacteria, and Candida albicans. TiO2 NPs were synthesized using the chemical methods, coated with carboxymethyl cellulose (CMC) and prepared in different concentrations (0.098, 0.196, 0.392, 0.784, 1.568, and 3.136 mg/mL). Eventually, a minimum inhibitory concentration (MIC) and a minimum biofilm inhibitory concentration (MBIC) were applied to investigate the effect of TiO2 NPs on microorganisms.
Results: According to the study results, the MICs of TiO2 NPs were found to be 1.489, 1.208, and 1.166 mg/ mL for Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae as the Gram-negative bacteria, respectively; and they were discovered to be 0.512, 0.830, and 0.707 mg/mL for Streptococcus pneumoniae, Staphylococcus aureus, and Staphylococcus epidermidis as the Gram-positive bacteria, respectively. As for C. albicans, as the yeast strain, MIC was 0.253 mg/ mL. The MBIC of more than 90% of TiO2 NPs was 6.25 mg/mL for both Gram-negative and Gram-positive bacterial types and 1.562 mg/mL for C. albicans.
Conclusions: It was concluded that TiO2 NPs were effective antimicrobial agents for Gram-positive bacteria, Gram-negative bacteria, and C. albicans, but their inhibitory effect on yeast was greater than that of bacteria.