Palmieri Valentina, Bugli Francesca, Lauriola Maria Carmela, Cacaci Margherita, Torelli Riccardo, Ciasca Gabriele, Conti Claudio, Sanguinetti Maurizio, Papi Massimiliano, De Spirito Marco
Physics Institute, Catholic University of Sacred Hearth, Largo Francesco Vito 1, 00168 Rome, Italy.
Institute for Complex Systems, National Research Council (ISC-CNR), Via dei Taurini 19, 00185 Rome, Italy.
ACS Biomater Sci Eng. 2017 Apr 10;3(4):619-627. doi: 10.1021/acsbiomaterials.6b00812. Epub 2017 Mar 2.
The development of new pharmacological strategies that evade bacterial resistance has become a compelling worldwide challenge. Graphene oxide (GO) can represent the nanotechnology answer being economical and easy to produce and to degrade and having multitarget specificity against bacteria. Several groups tried to define the interaction between GO sheets and human pathogens. Unfortunately, controversial results from inhibition to bacterial growth enhancement have been reported. The main difference among all experimental evidence relies on the environmental conditions adopted to study the bacteria-GO interaction. Indeed GO, stable in deionized water, undergoes a rapid and salt-specific DLVO-like aggregation that influences antimicrobial effects. Considering this phenomenon, the interaction of bacteria with GO aggregates having different sizes, morphologies, and surface potential can create a complex scenario that explains the contrasting results reported so far. In this article, we demonstrate that by modulating the GO stability in solution, the antibacterial or growth enhancement effect can be controlled on and . GO at low concentration cuts microorganism membranes and at high concentration forms complexes with pathogens and inhibits or enhances bacterial growth in a surface potential-dependent manner. With the framework defined in this study, the clinical application of GO gets closer, and controversial results in literature can be explained.
开发能够规避细菌耐药性的新药理学策略已成为一项紧迫的全球性挑战。氧化石墨烯（GO）可能是纳米技术的解决方案，它经济实惠、易于生产和降解，且对细菌具有多靶点特异性。多个研究团队试图确定氧化石墨烯片层与人类病原体之间的相互作用。不幸的是，已有报道称从抑制细菌生长到促进细菌生长的结果存在争议。所有实验证据的主要差异在于研究细菌与氧化石墨烯相互作用时所采用的环境条件。事实上，氧化石墨烯在去离子水中稳定，但会经历快速且具有盐特异性的类DLVO聚集，这会影响抗菌效果。考虑到这一现象，细菌与具有不同大小、形态和表面电位的氧化石墨烯聚集体之间的相互作用可能会产生一个复杂的情况，这可以解释迄今为止所报道的相互矛盾的结果。在本文中，我们证明通过调节氧化石墨烯在溶液中的稳定性，可以控制其对革兰氏阳性菌和革兰氏阴性菌的抗菌或生长促进作用。低浓度的氧化石墨烯会切割微生物膜，而高浓度的氧化石墨烯会与病原体形成复合物，并以表面电位依赖的方式抑制或促进细菌生长。基于本研究中所定义的框架，氧化石墨烯的临床应用更加接近现实，文献中相互矛盾的结果也能够得到解释。
