Smart Composites for Minimising Bacterial Biofilm Formation

细菌污染是医院环境中一直存在的危害，尽管采取了非常谨慎的措施来尽量减少风险，但这是一种非常常见的现象，会对患者的健康产生重大影响。在住院时间延长、治疗费用和工作日损失等方面，还将出现广泛的财政问题。由于有了通道，进入病人组织、血液供应、消化系统或泌尿系统的途径变得更加容易，这种情况就更加严重了。它们有多种形式，但无论应用如何，其核心功能都是相同的，即它们促进了血液、营养补充剂、药物等液体的直接输送。尽管它们在现代医疗保健中是一种宝贵的援助，但它们的使用却充满了困难，因为它们不幸也为细菌的直接传递开辟了一条途径，并且总是细菌感染的主要来源之一。鉴于目前对家庭保健倡议的重视，这可能会引起越来越多的关注。考虑到在临床环境中控制细菌污染的相关问题，可以预见，在不那么严格的家庭环境中，感染的可能性要大得多。使用抗生素是正常的临床手段，但它正开始受到收益递减的影响。一旦细菌附着在通道表面，它们往往会散发出一种保护性屏障，这种屏障可以最大限度地减少抗生素的影响，并可能导致耐药性的发展，反复再次感染需要过早去除通道。与通道相关的感染是一个长期以来一直在寻求解决方案的问题，尽管在制造这种管道时使用的材料已经取得了许多技术进步，以尽量减少细菌污染，但它们的作用往往是延迟而不是防止细菌定植。迫切需要重新思考和追求新技术，以最大限度地降低与外来细菌入侵相关的风险。拟议的项目旨在建立一个新的基础，从这个基础上解决生物膜的形成和防止菌种的定植。该方法是基于将许多不同的成分结合在一起，形成一种智能材料，当利用这种材料时，可以将生物流体中的氧气转化为更具活性的形式（超氧化物、过氧化物和羟基自由基），从而杀死微生物。该装置最初将以探针的形式存在，并沿着线的长度延伸，以保持内部表面没有细菌。然而，它可以转换成许多其他格式，比如智能绷带。然而，主要的原理是，该装置的底层表面将被设计成这样，即羟基自由基的数量可以被控制，从而提供抗菌作用，但不诱导溶栓作用，从而不影响患者的正常组织。关键是在探针表面的微位点上羟基自由基的周期性生成，在界面上提供离散的云，但在到达正常组织之前迅速扩散并被中和。该系统的一个关键优势是它不会导致抗菌素耐药性，可以在整个临床范围内连续使用，并且不需要患者接受更强效的全身抗生素治疗。

Bacterial contamination is an ever present hazard within hospital environments and while great care is taken to minimise the risk, it is nevertheless an all too common phenomena that can significantly impact on the wellbeing of the patient. There will also be wide ranging financial issues - in terms of the increased length of hospitalisation, cost of treatment and working days lost. The situation is exacerbated where access to the patient's tissues, blood supply, digestive or urinary system has been eased as a consequence of access lines. These take many forms but the core function is the same irrespective of application whereby they facilitate the direct delivery of fluids such as blood, nutritional supplements, drugs etc. Although an invaluable aid in modern healthcare, their use is however fraught with difficulty as they unfortunately also open a pathway for the direct delivery of bacteria and are invariably one of the major sources of bacterial infection. This is likely to be of increasing concern given the emphasis that is now being placed on healthcare at home initiatives. Given the problems associated with controlling bacterial contamination within a clinical environment, it could be anticipated that infection is much more probable within the less rigorous confines of the domestic home. The application of antibiotics is the normal clinical recourse but it is one that is beginning to suffer from diminishing returns. Once the bacteria have attached to the surface of the access line they tend to exude a protective barrier that can minimise the effects of the antibiotic and can led to the development of resistance with repeated re-infection necessitating the premature removal of the line. The access related infection is a problem that has long been seeking a solution and while many technological advancement have been made to the materials used in the fabrication of such lines to minimise bacterial contamination, their action tends to be one of delaying rather than preventing bacterial colonisation. There is an urgent need for a rethink and the pursuit of new technologies that can minimise the risk associated with adventitious bacterial ingressThe proposed project seeks to develop a new foundation from which to tackle the formation of the biofilm and prevent colonisation of the lines. The approach is based on bringing together a number of distinct components that can be fashioned in to a smart material that when harnessed can convert oxygen within the biological fluid into more reactive forms(superoxide, peroxide and hydroxyl radical) capable of killing the microbes. The device would initially be in the form of a probe that would reside within and extend along the length of the line and which would keep the internal surface free of bacteria. It could however be transferrable into a number of other formats - such as for smart bandages. The main rationale however is that the underlying surface of the device would be engineered in such way that the amount of hydroxyl radicals could be controlled so as to provide the antibacterial action but not induce a thrombolytic action and thereby not affect the normal tissues of the patient. Key to this is the periodic generation of the hydroxyl radical at microsites on the probe surface that provide discrete clouds at the interface but which diffuse rapidly and are neutralised before reaching the normal tissues. A key advantage of the system is that it does not contribute to antimicrobial resistance, can be used continuously and across the clinical spectrum and does not require the patient to be subject to ever more potent systemic antibiotics.