College of Chemical Engineering , Nanjing University of Science and Technology , Nanjing 210094 , China.
School of Chemical and Environmental Engineering , Jiangsu University of Technology , Changzhou 213002 , China.
ACS Appl Mater Interfaces. 2018 Oct 17;10(41):34905-34915. doi: 10.1021/acsami.8b10972. Epub 2018 Oct 4.
Biofilms contribute to persistent bacterial infections as well as formidable resistances to conventional antibiotics. However, it is still a major challenge to establish an advanced antibacterial nanoplatform that can efficiently eradicate biofilms while overcoming bacterial resistances. Taking advantage of the stimuli-responsive technique and the magnetic guidance strategy, here we present a highly efficient nanoplatform for planktonic inactivation and biofilm disruption. The multilayer films consisting of antibiotic gentamicin (Gen), tannic acid, and silver nanoparticles (AgNPs) were fabricated and coated on magnetic nanoparticles via electrostatic interactions. To achieve controlled drug release and improved biocompatibility, biodegradable hyaluronic acid was capped on the outer surface as a responsive shell. In vitro release profiles suggested that the nanocomposites showed both enzyme and pH-responsive release properties. The nanoplatform could be employed as a powerful nanocarrier for small molecular Gen and AgNPs delivery and on-demand release in response to bacterial infection microenvironment. The nanocomposites also showed satisfying antibacterial capacities against planktonic Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. Intriguingly, with magnetic field navigation (NdFeB, 2000 gauss), the nanocomposites could be guided to handily penetrate into S. aureus biofilm and performed dual-responsive release, showing significantly enhanced biofilm disruption. Moreover, excess reactive oxygen species production resulting from the nanocomposites contributed to the decomposition of biofilm matrix and ultimate biofilm eradication. As a consequence, the ingenious antibacterial nanoplatform could be promising for combating biofilm infections while overcoming bacterial resistances with extra environmental factors such as magnetic field.
生物膜不仅导致细菌感染持续存在，而且对传统抗生素也具有很强的抵抗力。然而，建立一种先进的抗菌纳米平台，能够有效地消除生物膜并克服细菌耐药性，仍然是一个重大挑战。利用刺激响应技术和磁导向策略，我们在这里提出了一种高效的浮游生物灭活和生物膜破坏的纳米平台。通过静电相互作用将由抗生素庆大霉素（Gen）、单宁酸和银纳米颗粒（AgNPs）组成的多层薄膜制备并涂覆在磁性纳米颗粒上。为了实现控制药物释放和提高生物相容性，将可生物降解的透明质酸作为响应性外壳覆盖在外表面。体外释放曲线表明，纳米复合材料具有酶和 pH 响应释放特性。该纳米平台可用作小分子 Gen 和 AgNPs 递送的强大纳米载体，并可按需响应细菌感染微环境进行释放。纳米复合材料还表现出对浮游态革兰氏阳性金黄色葡萄球菌和革兰氏阴性大肠杆菌的令人满意的抗菌能力。有趣的是，在磁场导航（NdFeB，2000 高斯）的作用下，纳米复合材料可以轻松地引导进入金黄色葡萄球菌生物膜，并进行双重响应释放，表现出显著增强的生物膜破坏能力。此外，纳米复合材料产生的过量活性氧物质有助于生物膜基质的分解和最终的生物膜清除。因此，这种巧妙的抗菌纳米平台有望在克服细菌耐药性的同时，通过额外的环境因素（如磁场）来对抗生物膜感染。
