Understanding Plasma Assisted Biofilm Inactivation

描述（由申请人提供）：生物膜每年在设备损坏，产品污染，感染以及设备和假体植入物的定植方面给美国造成数十亿美元的损失。与浮游生物相比，生物膜表现出非典型的特征，因此传统的微生物根除方法的有效性受到了极大的损害。因此，消灭这些生物的能力要求开发替代技术。该项目的长期目标是填补缺乏有效生物膜灭活/灭菌方法的空白。等离子体是物质的第四种状态，它的使用提供了一种新的选择，因为等离子体含有一种被单独称为杀菌剂的活性物质的混合物。尽管有证据表明血浆对灭活细菌生物膜是有用的，但在我们能够理解导致灭活/灭菌的机制并将其应用于医疗或环境目的之前，仍有许多未解决的问题。本研究的主要目的是了解导致气体放电等离子体辅助生物膜失活的机制。具体目的是：1)确定血浆对生物膜形成细胞生理状态的影响。我们将检验血浆影响生物膜形成细胞的生理状态（生存能力、培养能力、代谢状态）的假设，这种影响取决于生物膜暴露于血浆的时间和生物膜的年龄。2)测定等离子体对形成生物膜的细胞结构的影响。我们将验证等离子体影响生物膜形成细胞的结构（细胞包膜的完整性和最终孔隙的存在）的假设，这种影响取决于生物膜暴露于等离子体的时间和生物膜的年龄；3)将气等离子体组成与生物膜灭活/灭菌联系起来。我们将确定细胞对等离子体的反应是一种普遍现象，还是取决于所用等离子体的类型。我们将选择一个具有特定多样性或丰富的活性物质的等离子体环境，我们将用它来评估其对生物膜形成细胞结构和生理状态的影响。本研究将提供对血浆辅助生物膜失活及其机制的全面了解，实现NIH的目标#3。扩大医学和相关科学的知识基础，以提高国家的经济福利，并确保在研究方面的公共投资继续获得高回报)。通过实现这一主要目标，我们期望为一项技术的未来发展奠定基础，作为一个长期目标，解决一个严重的医学问题，实现NIH的使命（追求关于生命系统的性质和行为的基本知识的科学，并应用这些知识来延长健康的生命，减少疾病和残疾的负担）；特别是目标1（促进根本性的创造性发现、创新的研究策略及其应用，以此作为显著提高国家保护和改善健康能力的基础）。

DESCRIPTION (provided by applicant): Biofilms cost this nation billions of dollars yearly in equipment damage, product contamination, infections, and colonization of devices and prosthetic implants. The effectiveness of conventional methods of microbial eradication is drastically impaired with biofilms since they exhibit atypical characteristics when compared to their planktonic counterparts. Therefore the ability to destroy these organisms demands the development of alternative techniques. The broad, long term goal of this project is to fill a gap regarding the lack of effective biofilm inactivation/sterilization methods. The use of plasmas, the fourth state of the matter, offers a novel alternative since plasmas contain a mixture of reactive agents individually known as bacteria- killing agents. Although evidence suggests that plasma is useful to inactivate bacterial biofilms, there are still many unresolved questions before we can understand the mechanism that causes inactivation/sterilization and apply it for medical or environmental purposes. The main goal of this research is to understand the mechanisms leading to gas discharge plasma-assisted biofilm inactivation. The specific aims are: 1) to determine the effect of plasma on the physiological status of biofilms-forming cells. We will test the hypothesis that plasma affects the physiological status (viability, culturability, metabolic status) of biofilm- forming cells and the effect depends on the amount of time that biofilms have been exposed to plasma and the age of the biofilm. 2) to determine the effect of plasma on the structure biofilm-forming cells. We will test he hypothesis that plasma affects the structure (integrity of cell envelopes and eventual presence of pores) of biofilm-forming cells, and the effect depends on the amount of time that biofilms have been exposed to plasma and the age of the biofilm; and 3) to relate gas-plasma composition with biofilm inactivation/sterilization. We will determine whether the response of cells to plasma is a general phenomenon or if it depends on the type of plasma used. We will select a plasma environment with a particular diversity or abundance of reactive agents and we will use it to evaluate its effect on biofilm-forming cells structure and physiological status. This study will provide a comprehensive understanding of plasma-assisted-biofilm inactivation and its mechanisms, fulfilling NIH's goal #3 (to. expand the knowledge base in medical and associated sciences in order to enhance the Nation's economic well-being and ensure a continued high return on the public investment in research). By achieving this main goal we expect to build the basis for the future development of a technology that will, as a long-term goal, solve a serious medical problem, fulfilling NIH's mission (Science in pursuit of fundamental knowledge about the nature and behavior of living systems and the application of that knowledge to extend healthy life and reduce the burdens of illness and disability); and particularly goal # 1 (to foster fundamental creative discoveries , innovative research strategies, and their applications as a basis to advance significantly the Nation's capacity to protect and improve health). PUBLIC HEALTH RELEVANCE: Biofilms contaminate common household surfaces and many medical devices, (e.g., catheters, contact lenses, mechanical heart valves, joint replacements, etc.), causing illness and death. The huge doses of antimicrobials required to destroy biofilms are environmentally undesirable and may be hazardous to a patient. Therefore, the ability to destroy these organisms demands the development of alternative techniques. Plasmas, the fourth state of matter, offer an attractive alternative. This research will study the mechanisms of plasma-assisted- biofilm inactivation with the long term goal of developing an easy-to-use, non-hazardous sterilization method to destroy biofilms.