Tuning the ATP-triggered pro-oxidant activity of iron oxide-based nanozyme towards an efficient antibacterial strategy.
Tuning the ATP-triggered pro-oxidant activity of iron oxide-based nanozyme towards an efficient antibacterial strategy.
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DOI：
10.1016/j.jcis.2020.01.099
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发表时间：
2020-01
影响因子：
9.9
通讯作者：
N. V. S. Vallabani;A. Vinu;Sanjay Singh;Ajay S. Karakoti;Ajay S. Karakoti
中科院分区：
文献类型：
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作者：
N. V. S. Vallabani;A. Vinu;Sanjay Singh;Ajay S. Karakoti;Ajay S. Karakoti
细菌对各种抗生素的耐药性惊人地增加，使得设计替代或联合疗法来治疗顽固的细菌感染势在必行。从这个角度来看，像纳米酶这样的新兴工具，具有生物酶特征的纳米材料，正在被用来控制细菌病原体引起的感染。在几种用于抗菌的纳米酶中，fe3o4纳米颗粒（NP）因其有效的过氧化物酶活性而受到广泛关注。Fe3O4NP的pH依赖性过氧化物酶活性通过铁独特的Fenton化学反应产生dotOH自由基。然而,它们的pH依赖活性仅限于酸性环境，并且在接近中性pH时观察到抗菌活性的显着丧失。在这里，我们描述了一种新的策略，通过利用三磷酸腺苷二钠（ATP）作为增效剂来克服柠檬酸盐包被Fe3O4NP的pH缺陷，以加速治疗dotOH自由基的产生，并在广泛的pH范围内恢复其抗菌活性。这种增效组合（30µg/mL Fe3O4NP和2.5 mM ATP）显示出很高的增效性在H2O2存在下，在中性ph下，对革兰氏阳性（枯草芽孢杆菌）和革兰氏阴性（大肠杆菌）菌株均有杀菌活性。通过活力评估和膜损伤研究确定了协同作用（Fe3O4NP + ATP），并通过比较产生的根性dotOH自由基的浓度进一步证实了协同作用。总的来说，这项研究说明了ATP辅助和自由基dotoh介导的fe3o4纳米酶在接近中性pH下的杀菌活性。
An alarming increase in bacterial resistance towards various types of antibiotics makes it imperative to design alternate or combinational therapies to treat stubborn bacterial infections. In this perspective, emerging tools like nanozymes, nanomaterials with biological enzyme like characteristics, are being utilised to control infections caused by bacterial pathogens. Among several nanozymes used for antibacterial applications, Fe3O4nanoparticles (NP) received great attention due to their effective peroxidase like activity. The pH dependent peroxidase activity of Fe3O4NP results in generation ofradical dotOH radical via the unique Fenton chemistry of iron. However, their pH dependent activity is restricted to acidic environment and dramatic loss in antibacterial activity is observed at near neutral pH. Here we describe a novel strategy to overcome the pH lacunae of citrate coated Fe3O4NP by utilizing adenosine triphosphate disodium salt (ATP) as a synergistic agent to accelerate theradical dotOH radical production and restore its antibacterial activity over a wide range of pH. This synergistic combination (30 µg/mL Fe3O4NP and 2.5 mM ATP) shows a high bactericidal activity against both gram positive (B. subtilis) and gram negative (E. coli) bacterial strains, in presence of H2O2, at neutral pH. The synergistic effect (Fe3O4NP + ATP) is determined from the viability assessment and membrane damage studies and is further confirmed by comparing the concentration of generatedradical dotOH radicals. Over all, this study illustrates ATP assisted andradical dotOH-mediated bactericidal activity of Fe3O4nanozyme at near neutral pH.