Performance and Energy Efficiency of Low Irradiance Antimicrobial Blue Light for Continuous Decontamination Applications

多重耐药微生物的出现不仅对公共卫生构成重大风险，而且对全球卫生保健系统构成经济负担。抗菌405nm蓝光hins光是一种独特的感染控制方法，已被证明可以灭活广泛的微生物物种，包括那些具有抗生素耐药性的微生物物种。由于其独特的安全特性，它已被开发用作被动去污技术，允许对占用的环境进行连续消毒。本项目旨在通过研究这一新兴感染控制技术的基本光化学失活机制，特别是其使用低辐照度光子能量的操作方面，产生重要的新信息。与众所周知具有杀菌作用的紫外光不同，对405nm光的抗菌特性的认识是一个相对较新的科学发现。该领域的大部分文献都集中在证明抗菌原理上，为了做到这一点，研究倾向于使用高功率光源（高达150mW/cm2），以实现更快的抗菌效果。然而，这在将研究结果转化为实际应用时存在局限性，这些应用旨在使用低辐照水平。这对于持续环境去污技术的应用尤其重要，因为这些系统通常利用<0.5mW/cm2的辐照水平，以允许房间居住者安全，24/7暴露。最近由ROLEST小组生成的数据强调，与高强度光子水平相比，使用低辐照光子水平会导致微生物失活动力学的主要差异。样品的低辐照度照明显示出增强的抗菌效果和显著提高的能源效率。随着行业对照明系统能效的需求不断增长，理解这一基本概念并利用知识开发低功耗、节能的抗菌照明系统的能力将具有重要的研究和商业价值。该项目的目的和目标将包括：-深入的科学和技术文献综述，以建立有关抗菌蓝光的基本作用和应用的当前知识，包括对这些研究中报告的辐照度水平和能源效率进行综述。-设计和建造一个用于抗菌和能效测试的台式低辐照度光系统。为此需要进行重大的技术开发，以确保使用适当的LED光源和光学元件；冷/热管理;输出辐照度可控性；以及操作人员的安全。将对所建系统进行辐照度分析，以优化LED配置并确保低辐照度光分布的均匀性。-将进行抗菌测试，以评估一组关键生物对低辐照度光的敏感性。将建立辐照水平和剂量范围内的失活动力学。待检测的主要生物将包括ESKAPE病原体和病毒。将对临床和工业环境中常见的一系列相关表面（例如金属、聚合物、织物、玻璃）进行去污效果评估。-要确定的一个关键因素是抗菌功效的最低阈值水平。了解成功去污所需的最低辐照水平和暴露时间将是开发用于实际感染控制应用的低能量系统的关键因素。-还将对使用高辐照度光灭活微生物所需的能量进行比较，以便量化能量和杀菌效率的改进。

The emergence of multi-drug resistant microbes presents both a major risk to public health and an economic burden on the global healthcare system. Antimicrobial 405nm blue HINS-light is a unique method of infection control that has been proven to inactivate a broad range of microbial species including those with antibiotic resistance. Due to its unique safety features, it has been developed for use as a passive decontamination technology which permits continuous disinfection of occupied environments. This project aims to generate important new information on this emerging infection control technology by investigating aspects of its fundamental photo-chemical inactivation mechanism, specifically with respect to its operation using low irradiance photon energy. Unlike ultraviolet light, which possesses well-known germicidal action, the recognition of the antimicrobial properties of 405nm light is a relatively recent scientific discovery. Much of the literature in the area has focused on proving the antimicrobial principles, and to do this, studies have tended to utilise high power light sources (up to 150mW/cm2) in order to achieve faster antimicrobial effects. This however, has limitations when translating the findings towards practical applications which are designed to use low irradiance levels. This is particularly significant for the application of the technology for continuous environmental decontamination, as these systems typically utilise irradiance levels of <0.5mW/cm2 in order to permit safe, 24/7, exposure of room occupants.Recent data generated by the ROLEST group has highlighted that use of low irradiance photon levels results in major differences in the microbial inactivation kinetics when compared with high intensity photon levels. Low irradiance illumination of samples demonstrated enhanced antimicrobial efficacy and significantly improved energy efficiency. With the growing industry demand for energy efficiency in lighting systems, the ability to understand this fundamental concept and utilise the knowledge to develop low power, energy efficient antimicrobial lighting systems, will be of significant research and commercial interest. The project aims and objectives will include the following: -An in-depth scientific and technical literature review to establish current knowledge on the fundamental action and application of antimicrobial blue light, including a review of the irradiance levels and energy efficiencies reported in these studies.-Design and build of a bench-top, low irradiance light system which will be used for antimicrobial and energy efficiency testing. Significant technical development will be required for this in order to ensure the use of appropriate LED sources and optical components; cooling/thermal management; controllability of output irradiance; and operator safety. Irradiance profiling of the built system will be conducted to optimise LED configurations and ensure uniformity of the low irradiance light distribution.-Antimicrobial testing will be conducted to evaluate a panel of key organisms for their susceptibility to low irradiance light. Inactivation kinetics for a range of irradiance levels and doses will be established. Key organisms to be tested will include ESKAPE pathogens and viruses. Decontamination efficacy will be evaluated on a range of relevant surfaces common within clinical and industrial environments (e.g. metals, polymers, fabrics, glass). - A key factor to be established will be the minimum threshold level for antimicrobial efficacy. Knowledge of the minimum irradiance levels and exposure times required for successful decontamination will be a key factor in the development of low energy systems for practical infection control applications. -Comparisons will also be made to the energies required for microbial inactivation using high irradiance light in order to quantify improvements in energy and germicidal efficiency.