氧化石墨烯/二氧化锰异质结的抗菌性能评价及其抗菌机理研究

Evaluation of antibacterial properties of graphene oxide/manganese dioxide heterojunction and study on its antibacterial mechanism

传统的化学动力疗法(Chemodynamic therapy,CDT)往往依靠内源性H_(2)O_(2)产生·OH来对抗细菌,但是产生的·OH难以达到对细菌的彻底清除。此外,细菌内部遭受活性氧攻击时会产生大量的还原型谷胱甘肽(Glutathione,GSH),抑制活性氧(ROS)对细菌的杀伤作用,增加清除细菌的难度。因此,设计并开发了一种由氧化石墨烯(Graphene oxide)/二氧化锰(MnO_(2))组成的生物异质结(Biological heterojunction,Bio-HJs)平台。在近红外光照射下,Bio-HJs不仅具有光热效应,还能催化H_(2)O_(2)与Mn^(2+)氧化生成高致死性活性氧;同时,生成的Mn^(4+)离子可以大量消耗细菌内的谷胱甘肽,破坏其防御系统。细菌实验进一步证实,制得的Bio-HJs具有强大的抗菌能力,可以有效根治细菌感染。

Traditional Chemodynamic Therapy(CDT)often relies on endogenous H_(2)O_(2)to generate·OH to fight bacteria,but the generated·OH is difficult to clear bacteria completely.In addition,the bacteria can generate a large amount of reduced glutathione(GSH)when they are attacked by reactive oxygen species,which inhibits the killing effect of reactive oxygen species(ROS)on bacteria and increases the difficulty in removing bacteria.Therefore,a biological heterojunction(Bio-HJs)platform composed of graphene oxide/manganese dioxide(MnO_(2))is designed and developed.Under near-infrared irradiation,Bio-HJs have photothermal effects,and also catalyze the oxidation of H_(2)O_(2)and Mn^(2+)to generate highly lethal reactive oxygen species.Meanwhile,the resulted Mn^(4+)can deplete glutathione in bacteria in large quantities,disrupting their defense system.It is further verified by bacterial experiments that Bio-HJs have strong antibacterial ability and can effectively cure bacterial infections.