Biofilm Resistant Liquid-like Solid Surfaces in Flow Situations

生物膜是指微生物细胞嵌入一种附着在底物上的自分泌的细胞外聚合物（EPS）基质中。从医学到工业再到环境，生物膜在各种应用领域都是一些最紧迫的全球挑战的核心，并产生了相当大的经济和社会影响。例如，据估计，仅在英国，医院中导尿管相关性尿路感染（CAUTI）就造成了10 - 25亿英镑的额外保健费用（Ramstedt等人，Macromolec）。并导致每年2000多人死亡（Feneley et al .， J. Med. Eng.）。technology . 39, 2015)。为了对抗表面上的生物膜生长，使用固定化抗菌剂（即抗生素、银颗粒）的化学方法可引发抗菌素耐药性（AMR），但通常不可持续。另外，可以使用仿生纳米结构表面（例如蝉翅、荷叶），但它们的效果通常不会持久。最近一项创造光滑表面的创新受到了肉食性猪笼草光滑表面策略的启发。这些光滑的表面包括在多孔或有纹理的固体表面上浸渍一种锁定在结构中的液体润滑剂。这种液体表面已经被证明有希望作为防污表面，通过抑制生物膜附着、粘附和生长直接接近固体表面。然而，由于流动导致润滑剂耗竭，这些新型液体表面在流动条件下的抗菌膜性能仍然是一个值得关注的问题。在这里，我们提出了一种新的抗生物膜表面，通过创建永久结合光滑的液体状固体表面。成功将改变我们对生活在表面上的细菌的理解，并为下一代抗菌膜表面的广泛应用（例如生物医学设备和船体）的开发开辟新的设计范例。为了使这个项目的成功交付，它需要我们结合跨学科的技能，从材料化学、材料表面的物理和化学特征、纳米力学、微生物学、生物力学到计算力学。该项目的目标与EPSRC医疗技术大挑战非常一致，解决了控制所需物理干预量、优化治疗和改变社区卫生和护理的主题。与此同时，我们将促进跨领域研究能力的进步（例如，先进材料、未来制造技术和医疗设备的可持续设计），这对应对这些重大挑战至关重要。特别是，本研究将采用纳米力学测试来确定细菌粘附和微流体技术的生物膜表征，这使我们能够通过制定和验证细菌附着和生物膜力学的复杂数值模型，在计算工程中创造新的方法。

Biofilms are microbial cells embedded within a self-secreted extracellular polymeric substance (EPS) matrix which adhere to substrates. Biofilms are central to some of the most urgent global challenges across diverse fields of application, from medicine to industry to the environment and exert considerable economic and social impact. For example, catheter-associated urinary tract infections (CAUTI) in hospitals has been estimated to cause additional health-care costs of £1-2.5 billion in the United Kingdom alone (Ramstedt et al, Macromolec. Biosci. 19, 2019) and to cause over 2000 deaths per year (Feneley et al, J. Med. Eng. Technol. 39, 2015). To combat biofilm growth on surfaces, chemical-based approaches using immobilization of antimicrobial agents (i.e. antibiotics, silver particles) can trigger antimicrobial resistance (AMR), but are often not sustainable. Alternatively, bio-inspired nanostructured surfaces (e.g. cicada wing, lotus leaf) can be used, but their effects often may not last. A recent innovation in creating slippery surfaces has been inspired by the slippery surface strategy of the carnivorous Nepenthes pitcher plant. These slippery surfaces involve the impregnation of a porous or textured solid surface with a liquid lubricant locked-in to the structure. Such liquid surfaces have been shown to have promise as antifouling surfaces by inhibiting the direct access to the solid surface for biofilm attachment, adhesion and growth. However, the antibiofilm performance of these new liquid surfaces under flow conditions remains a concern due to flow-induced depletion of lubricant. Here we propose a novel anti-biofilm surface by creating permanently bound slippery liquid-like solid surfaces. Success would transform our understanding about bacteria living on surfaces and open-up new design paradigms for the development of next generation antibiofilm surfaces for a wide range of applications (e.g. biomedical devices and ship hulls). To enable the successful delivery of this project, it requires us to combine cross-disciplinary skills ranging from materials chemistry, physical and chemical characterisations of materials surfaces, nanomechanics, microbiology, biomechanics, to computational mechanics. The project objectives well align with EPSRC Healthcare Technologies Grand Challenges, addressing the topics of controlling the amount of physical intervention required, optimizing treatment, and transforming community health and care. In parallel, we shall contribute to the advancement of Cross-Cutting Research Capabilities (e.g. advanced materials, future manufacturing technologies and sustainable design of medical devices) that are essential for delivering these Grand Challenges. In particular, this research will employ nanomechanical tests to determine bacteria adhesion and microfluidics techniques for biofilm characterisation, which enables us to create novel approaches in computational engineering through the formulation and validation of sophisticated numerical models of bacteria attachment and biofilm mechanics.