Ultra-Liquid-Repellent Surfaces: from wetting to anti-biofouling properties

超防液表面：从润湿性能到抗生物污损性能

• 批准号: EP/W010852/1
• 负责人: Nan Gao
• 金额: $ 40.03万
• 依托单位: University of Birmingham
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FW010852%2F1
• 关键词: Ultra; Liquid; Repellent; Surfaces; wetting

Significant incidence of hospital-acquired infections due to fouling of biomedical devices, which are major public health threats contributing to prolonged hospital stay and death, has generated much attention over the past two decades. For example, indwelling urinary catheters are responsible for most hospital-acquired urinary tract infections (UTIs), which account for approximately 35-40% of all hospital-acquired infections. This is followed by surgical site infections that account for 20% of all hospital-acquired infections. The pathogenesis of these infections is related to the susceptibility of device/instrument surfaces to bacterial adhesion and microbial colonization. Under these circumstances, invasion of the bacteria to human bodies via medical devices such as surgical instruments and catheters (e.g., migrating along the urinary tract to the bladder and kidneys) is made utterly easy by the spreading and adhesion of liquids such as contaminated urine, blood and even water/moisture. However, due to insufficient attention to and understanding of wetting and adhesion of complex physiological fluids on the surfaces (both external and internal) of biomedical devices, there has been rather limited progress in preventing fouling-associated infections.This proposal aims to gain an in-depth understanding of wetting and adhesion for anti-biofouling surfaces relevant for biomedical devices. 'Wetting' refers to how a liquid deposited on a surface spreads out. The phenomena of wetting are governed by interfacial tension and surface structure. In the case of droplets of liquid on a non-wettable surface, the droplets can form a roughly spherical shape, exhibiting a contact angle approaching 180 degrees. This allows droplets that are in contact with a liquid repellent surface to slide/roll off easily and remove surface contamination. By contrast, droplets will spread spontaneously on fully wettable solid surfaces to form a thin film. Recent advances in wetting-based applications have demonstrated that surfaces with extreme liquid repellence have great potential to facilitate anti-biofouling properties. Design and application of surfaces with improved durability and anti-biofouling properties whereby wetting and adhesion behaviours can be manipulated will be demonstrated in this work. Firstly, we will use state-of-the-art fabrication techniques to prepare various liquid repellent surfaces. This will allow us to compare and optimise the liquid repellence of the fabricated surface patterns, and thereby, prevent the impalement of the liquid into the fabricated surface structure in order to avoid contamination and corrosion. Specifically, we will investigate the wetting and adhesion behaviours of complex liquids, including urine and blood, to facilitate the development of ultra-liquid-repellent surfaces. We will develop methods to test how the surface properties are affected by interactions with various liquids. Where applicable, we will assess the impact of surface defects before and after interactions with the contaminating liquids. This is to improve the inherent antifouling properties by reducing surface-associated biofilm growth resulting from surface defects. Understanding how liquid repellence varies is key to enabling researchers to design robust anti-biofouling surfaces that can be used on medical devices with internal surfaces (such as catheters and colostomy bags) and medical-grade metals against aggressive contamination and corrosion.

在过去的二十年中，由于生物医学设备的结垢而引起的医院获得感染的大量发生率是导致长期住院和死亡的主要公共卫生威胁，这引起了很多关注。例如，留置尿导管负责大多数医院获得的尿路感染（UTI），占所有医院获得感染的约35-40％。接下来是手术部位感染，占所有医院获得感染的20％。这些感染的发病机理与装置/仪器表面对细菌粘附和微生物定殖的敏感性有关。在这种情况下，通过医疗设备（例如，沿着尿道迁移到膀胱和肾脏迁移）将细菌侵入人体向人体侵袭，这是通过污染液体，血液，血液甚至水/水分/水分的传播和粘附而变得非常容易的。然而，由于对生物医学设备的表面（外部和内部）对润湿的关注和了解和对润湿的粘附的理解和粘附，因此在防止结垢相关感染方面取得了相当有限的进展。该建议的目的是获得对润湿和粘附的抗蛋白相关性的，以获取对抗螺旋的了解。 “润湿”是指沉积在表面上的液体如何扩散。润湿现象由界面张力和表面结构控制。对于在不可焊接表面上的液体液滴的情况下，液滴可以形成大致的球形形状，表现出接近180度的接触角。这允许与液体驱虫表面接触的液滴轻松滑动/滚动并去除表面污染。相比之下，液滴会自发地在完全润湿的固体表面上散布以形成薄膜。基于润湿的应用的最新进展表明，具有极端液体排斥的表面具有促进抗生物形式特性的巨大潜力。在这项工作中可以证明具有提高耐用性和抗生物形式特性的表面的设计和应用，从而可以操纵润湿和粘附行为。首先，我们将使用最先进的制造技术来准备各种液体驱虫表面。这将使我们能够比较和优化制造的表面图案的液体排斥，从而防止液体将液体刺激到制造的表面结构中，以避免污染和腐蚀。具体而言，我们将研究包括尿液和血液在内的复杂液体的润湿和粘附行为，以促进超液体固定表面的发展。我们将开发方法来测试表面特性如何受到各种液体相互作用的影响。如果适用，我们将评估与污染液体相互作用之前和之后的表面缺陷的影响。这是通过降低表面缺陷导致的表面相关生物膜生长来改善固有的防污特性。了解液体排斥性如何变化是使研究人员能够设计可在具有内部表面（例如导管和结肠造口术袋）的医疗设备上使用的稳健抗双性反面表面，以及可抵抗侵略性污染和腐蚀的医学级金属。

项目成果

Droplet impact on doubly re-entrant structures.

• DOI: 10.1038/s41598-024-52951-2
• 发表时间: 2024-02-01
• 期刊: Scientific reports
• 影响因子: 4.6