Caratto Valentina, Ball Lorenzo, Sanguineti Elisa, Insorsi Angelo, Firpo Iacopo, Alberti Stefano, Ferretti Maurizio, Pelosi Paolo
Dipartimento di Chimica e Chimica Industriale, Università degli Studi di Genova, Genova, Italy.
Istituto CNR SPIN - Genova, Italy.
Rev Bras Ter Intensiva. 2017 Jan-Mar;29(1):55-62. doi: 10.5935/0103-507X.20170009.
: The aim of this study was to assess the antibacterial activity against Staphylococcus aureus and Pseudomonas aeruginosa of two nanoparticle endotracheal tube coatings with visible light-induced photocatalysis.
: Two types of titanium dioxide nanoparticles were tested: standard anatase (TiO2) and N-doped TiO2 (N-TiO2). Nanoparticles were placed on the internal surface of a segment of commercial endotracheal tubes, which were loaded on a cellulose acetate filter; control endotracheal tubes were left without a nanoparticle coating. A bacterial inoculum of 150 colony forming units was placed in the endotracheal tubes and then exposed to a fluorescent light source (3700 lux, 300-700 nm wavelength) for 5, 10, 20, 40, 60 and 80 minutes. Colony forming units were counted after 24 hours of incubation at 37°C. Bacterial inactivation was calculated as the percentage reduction of bacterial growth compared to endotracheal tubes not exposed to light.
: In the absence of light, no relevant antibacterial activity was shown against neither strain. For P. aeruginosa, both coatings had a higher bacterial inactivation than controls at any time point (p < 0.001), and no difference was observed between TiO2 and N-TiO2. For S. aureus, inactivation was higher than for controls starting at 5 minutes for N-TiO2 (p = 0.018) and 10 minutes for TiO2 (p = 0.014); inactivation with N-TiO2 was higher than that with TiO2 at 20 minutes (p < 0.001), 40 minutes (p < 0.001) and 60 minutes (p < 0.001).
: Nanosized commercial and N-doped TiO2 inhibit bacterial growth under visible fluorescent light. N-TiO2 has higher antibacterial activity against S. aureus compared to TiO2.
本研究旨在评估两种具有可见光诱导光催化作用的纳米颗粒气管内导管涂层对金黄色葡萄球菌和铜绿假单胞菌的抗菌活性。
测试了两种类型的二氧化钛纳米颗粒：标准锐钛矿型（TiO₂）和氮掺杂TiO₂（N-TiO₂）。将纳米颗粒置于一段商用气管内导管的内表面，该导管加载在醋酸纤维素滤膜上；对照气管内导管未进行纳米颗粒涂层处理。将150个菌落形成单位的细菌接种物置于气管内导管中，然后暴露于荧光光源（3700勒克斯，波长300 - 700纳米）下5、10、20、40、60和80分钟。在37°C孵育24小时后计算菌落形成单位。细菌失活率计算为与未暴露于光的气管内导管相比细菌生长减少百分比。
在无光条件下，对两种菌株均未显示出相关抗菌活性。对于铜绿假单胞菌，在任何时间点，两种涂层的细菌失活率均高于对照组（p < 0.001），且TiO₂和N-TiO₂之间未观察到差异。对于金黄色葡萄球菌，N-TiO₂在5分钟时失活率高于对照组（p = 0.018），TiO₂在10分钟时失活率高于对照组（p = 0.014）；在20分钟（p < 0.
