Photodynamic Inactivation of Pseudomonas aeruginosa by PHEMA Films Loaded with Rose Bengal: Potentiation Effect of Potassium Iodide

Polymers

Ana M. López-Fernández¹  Ignacio Muñoz Resta¹  Francisco Galindo¹  Rosa de Llanos² 

[1] Departamento de Química Inorgánica y Orgánica, Universitat Jaume I, Av. V. Sos Baynat s/n, 12071 Castellón, Spain;Unidad Predepartamental de Medicina, Universitat Jaume I, Av. V. Sos Baynat s/n, 12071 Castellón, Spain;

关键词: PHEMA;    Rose Bengal;    photodynamic inactivation;    antimicrobial materials;    bactericidal materials;    Pseudomonas aeruginosa;   

DOI  :  10.3390/polym13142227

来源: DOAJ

【 摘 要 】

Four formulations have been used to produce different poly(2-hydroxyethyl methacrylate) (PHEMA) thin films, containing singlet oxygen photosensitizer Rose Bengal (RB). The polymers have been characterized employing Thermogravimetric Analysis (TGA), Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR) and UV-vis Absorption Spectroscopy. When irradiated with white light (400–700 nm) films generated singlet oxygen (¹O₂), as demonstrated by the reactivity with ¹O₂ trap 9,10-dimethylanthracene (DMA). Material with the highest RB loading (polymer A4, 835 nmol RB/g polymer) was able to perform up to ten cycles of DMA oxygenation reactions at high conversion rates (ca. 90%). Polymer A4 was also able to produce the complete eradication of a Pseudomonas aeruginosa planktonic suspension of 8 log₁₀ CFU/mL, when irradiated with white light (total dose 72 J/cm²). The antimicrobial photodynamic effect was remarkably enhanced by adding potassium iodide (100 mM). In such conditions the complete bacterial reduction occurred with a total light dose of 24 J/cm². Triiodide anion (I₃⁻) generation was confirmed by UV-vis absorption spectroscopy. This species was detected inside the PHEMA films after irradiation and at concentrations ca. 1 M. The generation of this species and its retention in the matrix imparts long-lasting bactericidal effects to the RB@PHEMA polymeric hydrogels. The polymers here described could find potential applications in the medical context, when optimized for their use in everyday objects, helping to prevent bacterial contagion by contact with surfaces.

【 授权许可】

Unknown