Antimicrobial polymers: Antibacterial efficacy of silicone rubber–titanium dioxide composites

Abstract

Control and reduction of microorganism infections in high-risk environments is up to date a challenge. Traditional techniques imply several limitations including development of antibiotics resistance and ecotoxicity. Then, polymers functionalized with photocatalyts arise as a promising solution against a broad spectrum of microorganisms found at, e.g. sanitary, food, and medical environments. Here, we present silicone rubber–TiO2 composites as novel antibacterial polymers. Four different types of composites with different TiO2 contents were produced and analyzed under UV irradiation and dark conditions in terms of particle distribution, chemical composition, photocatalytic activity, wettability, and antibacterial efficacy against Escherichia coli. Under UV irradiation, antibacterial sensitivity assay showed a 1000 times reduction of colony forming units after 2 h of light exposure so that the antibacterial ability of silicone–TiO2 composites was proved. Photocatalytic activity assessment suggested that reactive oxygen species induced by photocatalytic reaction at TiO2 particles are the main cause of the observed antibacterial effect. Scanning electron microscopy indicated no topographical damage after UV exposure. In addition, chemical analysis through Raman and X-Ray photoelectron spectroscopies demonstrated the stability of the silicone matrix under UV irradiation. Hence, the current work presents silicone–TiO2 composites as stable nonspecific antibacterial polymers for prevention of infections at multiple high-risk environments.

Titanium Dioxide/Polysiloxane Composites: Preparation, Characterization and Study of Their Color Stability Using Thermochromic Pigments

“…The bactericidal effects of TiO 2 on E. coli have also been demonstrated by other researchers [29,[31][32][33]. The antibacterial effect of UV/TiO 2 photocatalysis is due to the production of reactive oxygen species (ROS: O 2…”

Polymeric Materials with Antibacterial Activity: A Review

“…For that purpose, TEM and SEM (SEM-EDX) measurements are done to observe particle distribution. Sometimes, EDX is used to obtain mappings of the elements in the composite materials, confirming the distribution of the particles within the polymer matrix [ 155 , 156 ].…”

Simultaneous Grafting Polymerization of Acrylic Acid and Silver Aggregates Formation by Direct Reduction Using γ Radiation onto Silicone Surface and Their Antimicrobial Activity and Biocompatibility

“…One of the most common strategies to provide antimicrobial activity to surfaces (e.g., carbon nanomaterials [ 7 , 8 ], inorganic substrates [ 9 , 10 ], and polymeric substrates [ 11 ]) is the immobilization of antimicrobial agents through interactions between the antimicrobials and grafted polymer chains onto the base material or by covalent attachment of the antimicrobial to the surface of the base material [ 12 , 13 ]. These antimicrobial agents may be both organic (classical molecular antibiotics) or inorganic (metallic particles) in nature; however, the latter have attracted more attention because the use of classical antibiotics still increase concerns for bacterial antibiotic resistance [ 14 , 15 ].…”