Advanced Porous Materials Unit (APMU), IMDEA Energy Institute, Avda. Ramón de la Sagra 3, E-28935 Móstoles, Madrid, Spain; Department of Inorganic Chemistry I, Chemical Sciences Faculty, Complutense University of Madrid, 28040 Madrid, Spain.
Department of Chemical Engineering, University of Alcalá, E-28871 Alcalá de Henares, Madrid, Spain.
Acta Biomater. 2019 Oct 1;97:490-500. doi: 10.1016/j.actbio.2019.08.011. Epub 2019 Aug 6.
Surface biofilm inhibition is still currently a considerable challenge. Among other organisms, Staphylococcus aureus is notable for its ability to form a strong biofilm with proved resistance to chemotherapy. Contamination of high-touch surfaces with S. aureus biofilm not only promotes disease spread but also generates tremendous health-associated costs. Therefore, development of new bactericidal and antiadhesive surface coatings is a priority. Considering that metal-organic frameworks (MOFs) have recently emerged as promising antibacterial agents, we originally report here the synthesis of a multi-active silver-containing nanoscaled MOF composite as a potential surface coating against S. aureus biofilm owing to a triple effect: intrinsic bactericide activity of the MOF, biocidal character of silver nanoparticles (AgNPs), and photoactivity after UVA irradiation. AgNPs were successfully entrapped within the benchmarked nanoscaled porous photoactive titanium(IV) aminoterephthalate MIL-125(Ti)NH using a simple and efficient impregnation-reduction method. After complete characterization of the composite thin film, its antibacterial and anti-adherent properties were fully evaluated. After UVA irradiation, the composite coating exhibited relevant bacterial inhibition and detachment, improved ligand-to-cluster charge transfer, and steady controlled delivery of Ag. These promising results establish the potential of this composite as an active coating for biofilm treatment on high-touch surfaces (e.g., surgical devices, door knobs, and rail bars). STATEMENT OF SIGNIFICANCE: Surface contamination due to bacterial biofilm formation is still a demanding issue, as it causes severe disease spread. One possible solution is the development of antifouling and antibacterial surface coatings. In this work, we originally propose the use of photoactive metal-organic frameworks (MOFs) for biofilm treatment. The novelty of this work relies on the following: i) the treatment of strongly contaminated surfaces, as previous studies with MOFs have exclusively addressed biofilm prevention; ii) this pioneering work reports both antiadherent effect, which removes the biofilm, and bacterial inhibition; iii) our original successful strategy has never been proposed thus far, involving the multi-active combination of 1) intrinsic antibacterial effect of a photoactive titanium-based nanoMOF, 2) immobilization of biocide silver nanoparticles, and 3) improved anti-bioadherent effect upon irradiation of the composite coating.
表面生物膜抑制仍然是一个相当大的挑战。在其他生物体中，金黄色葡萄球菌因其能够形成具有抗化疗能力的强生物膜而引人注目。高接触表面被金黄色葡萄球菌生物膜污染不仅会促进疾病传播，还会产生巨大的与健康相关的成本。因此，开发新的杀菌和抗粘表面涂层是当务之急。考虑到金属有机骨架（MOFs）最近作为有前途的抗菌剂出现，我们最初在这里报告了一种多活性含银纳米级 MOF 复合材料的合成，该复合材料作为一种潜在的表面涂层，可抵抗金黄色葡萄球菌生物膜，原因有三：MOF 的固有杀菌活性、银纳米粒子（AgNPs）的杀菌特性以及 UVA 照射后的光活性。AgNPs 成功地通过简单有效的浸渍还原法被捕获到基准纳米多孔光活性钛（IV）氨基对苯二甲酸 MIL-125（Ti）NH 中。对复合薄膜进行了完全表征后，对其抗菌和抗黏附性能进行了全面评估。经 UVA 照射后，复合涂层表现出相关的细菌抑制和脱落，改善了配体-簇电荷转移，并实现了 Ag 的稳定可控释放。这些有前景的结果确立了该复合材料作为高接触表面（例如手术器械、门把手和栏杆）生物膜处理的活性涂层的潜力。
由于细菌生物膜的形成导致的表面污染仍然是一个具有挑战性的问题，因为它会导致严重的疾病传播。一种可能的解决方案是开发防污和抗菌表面涂层。在这项工作中，我们最初提出使用光活性金属有机骨架（MOFs）来处理生物膜。这项工作的新颖之处在于：i）处理污染严重的表面，因为以前的 MOFs 研究仅解决了生物膜的预防问题；ii）这项开创性的工作报告了抗黏附作用，可去除生物膜，以及细菌抑制作用；iii）我们原始的成功策略迄今为止从未被提出过，涉及多活性组合 1）光活性基于钛的纳米 MOF 的固有抗菌作用，2）固定化生物杀灭银纳米粒子，以及 3）复合涂层照射后的抗生物附着效果的提高。
