BACKGROUND Bacterial biofilms are communities of surface-associated microorganisms living in cellular clusters or micro-colonies, encapsulated in a complex matrix composed of an extracellular polymeric substance, separated by open water channels that act as a circulatory system that enable better diffusion of nutrients and easier removal of metabolic waste products. The monitoring of biofilms can provide important information on fundamental biofilm-related processes. That information can shed light on the bacterial processes and enable scientists to find ways of preventing future bacterial infections. Various approaches in use for biofilm analysis are based on microscopic, spectrochemical, electrochemical, and piezoelectrical methods. All these methods provide significant progress in understanding the bio-process related to biofilm formation and eradication, nevertheless, the development of novel approaches for the real-time monitoring of biochemical, in particular metabolic activity, of bacterial species during the formation, life and eradication of biofilms is of great potential importance. RESULTS Here, detection and monitoring of the metabolic activity of bacterial biofilms in high-ionic-strength solutions were enabled as a result of novel surface modification by an active redox system, composed of 9,10-dihydroxyanthracene/9,10-anthraquinone, on the oxide layer of the SiNW, yielding a chemically-gated FET array. With the use of enzymatic reactions of oxidases, metabolites can be converted to H2O2 and monitored by the nanosensors. Here, the successful detection of glucose metabolites in high-ionic-strength solutions, such as bacterial media, without pre-processing of small volume samples under different conditions and treatments, has been demonstrated. The biofilms were treated with antibiotics differing in their mechanisms of action and were compared to untreated biofilms. Further examination of biofilms under antibiotic treatment with SiNW-FET devices could shed light on the bioprocess that occurs within the biofilm. Moreover, finding proper treatment that eliminates the biofilm could be examined by the novel nanosensor as a monitoring tool. CONCLUSIONS To summarize, the combination of redox-reactive SiNW-FET devices with micro-fluidic techniques enables the performance of rapid, automated, and real-time metabolite detection with the use of minimal sample size, noninvasively and label-free. This novel platform can be used as an extremely sensitive tool for detection and establishing medical solutions for bacterial-biofilm eradication and for finding a proper treatment to eliminate biofilm contaminations. Moreover, the sensing system can be used as a research tool for further understanding of the metabolic processes that occur within the bacterial biofilm population.

中文翻译：

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通过氧化还原反应纳米传感器阵列实时监测细菌生物膜代谢活动。


背景技术细菌生物膜是生活在细胞簇或微菌落中的表面相关微生物群落，封装在由细胞外聚合物质组成的复杂基质中，由开放水通道分隔开，开放水通道充当循环系统，使营养物质能够更好地扩散并且更容易去除代谢废物。生物膜的监测可以提供有关生物膜相关基本过程的重要信息。这些信息可以揭示细菌的过程，并使科学家能够找到预防未来细菌感染的方法。用于生物膜分析的各种方法基于显微镜、光谱化学、电化学和压电方法。所有这些方法在理解与生物膜形成和根除相关的生物过程方面都取得了重大进展，然而，实时监测细菌物种在形成、生活和根除过程中的生化、特别是代谢活性的新方法的开发生物膜的形成具有巨大的潜在重要性。结果在这里，通过活性氧化还原系统（由 9,10-二羟基蒽/9,10-蒽醌组成）进行新型表面修饰，可以检测和监测高离子强度溶液中细菌生物膜的代谢活性。 SiNW 的氧化层，产生化学门控 FET 阵列。通过使用氧化酶的酶促反应，代谢物可以转化为 H2O2 并由纳米传感器进行监测。在这里，已经证明可以成功检测高离子强度溶液（例如细菌培养基）中的葡萄糖代谢物，而无需在不同条件和处理下对小体积样品进行预处理。 用作用机制不同的抗生素处理生物膜，并与未经处理的生物膜进行比较。使用 SiNW-FET 装置对抗生素处理下的生物膜进行进一步检查，可以揭示生物膜内发生的生物过程。此外，可以通过新型纳米传感器作为监测工具来检查找到消除生物膜的适当治疗方法。结论 总而言之，氧化还原反应 SiNW-FET 器件与微流体技术的结合能够使用最小的样本量、无创且无标记地实现快速、自动化和实时的代谢物检测。这种新颖的平台可用作极其灵敏的工具，用于检测和建立根除细菌生物膜的医疗解决方案，以及寻找消除生物膜污染的适当治疗方法。此外，传感系统可以用作进一步了解细菌生物膜群体内发生的代谢过程的研究工具。