Barros Joana, Grenho Liliana, Fontenente Sílvia, Manuel Cândida M, Nunes Olga C, Melo Luís F, Monteiro Fernando J, Ferraz Maria P
FEUP - Faculdade de Engenharia, Departamento de Engenharia Metalúrgica e Materiais, Universidade do Porto, Portugal.
i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal.
J Biomed Mater Res A. 2017 Feb;105(2):491-497. doi: 10.1002/jbm.a.35925. Epub 2016 Oct 31.
Implant-associated infections are caused by surface-adhering microorganisms persisting as biofilms, resistant to host defense and antimicrobial agents. Given the limited efficacy of traditional antibiotics, novel strategies may rely on the prevention of such infections through the design of new biomaterials. In this work, two antimicrobial agents applied to nanohydroxyapatite materials-namely, chlorhexidine digluconate (CHX) and zinc oxide (ZnO) nanoparticles-were compared concerning their ability to avoid single- or dual-species biofilms of Staphylococcus aureus and Escherichia coli. The resulting biofilms were quantified by the enumeration of colony-forming units and examined by confocal microscopy using both Live/Dead staining and bacterial-specific fluorescent in situ hybridization. The sessile population arrangement was also observed by scanning electron microscopy. Both biomaterials showed to be effective in impairing bacterial adhesion and proliferation for either single- or dual-species biofilms. Furthermore, a competitive interaction was observed for dual-species biofilms wherein E. coli exhibited higher proliferative capacity than S. aureus, an inverse behavior from the one observed in single-species biofilms. Therefore, either nanoHA-CHX or nanoHA-ZnO surfaces appear as promising alternatives to antibiotics for the prevention of devices-related infections avoiding the critical risk of antibiotic-resistant strains emergence. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 491-497, 2017.
植入物相关感染是由作为生物膜持续存在的表面附着微生物引起的，这些微生物对宿主防御和抗菌剂具有抗性。鉴于传统抗生素的疗效有限，新策略可能依赖于通过设计新型生物材料来预防此类感染。在这项工作中，比较了应用于纳米羟基磷灰石材料的两种抗菌剂，即葡萄糖酸氯己定（CHX）和氧化锌（ZnO）纳米颗粒，它们避免金黄色葡萄球菌和大肠杆菌单物种或双物种生物膜形成的能力。通过计数菌落形成单位对所得生物膜进行定量，并使用活/死染色和细菌特异性荧光原位杂交通过共聚焦显微镜进行检查。还通过扫描电子显微镜观察了固着菌的群体排列。两种生物材料对单物种或双物种生物膜的细菌粘附和增殖均显示出有效的抑制作用。此外，在双物种生物膜中观察到竞争相互作用，其中大肠杆菌表现出比金黄色葡萄球菌更高的增殖能力，这与在单物种生物膜中观察到的行为相反。因此，纳米羟基磷灰石-葡萄糖酸氯己定（nanoHA-CHX）或纳米羟基磷灰石-氧化锌（nanoHA-ZnO）表面似乎是预防与器械相关感染的有前景的抗生素替代品，可避免出现抗生素耐药菌株的重大风险。©2016威利期刊公司。《生物医学材料研究杂志》A部分：105A：491 - 497，2017年。
