An integrated NMR/magnetic nanosensor system for detection of bacteria and toxins

用于检测细菌和毒素的集成核磁共振/磁性纳米传感器系统

• 批准号: 7915429
• 负责人: J Manuel Perez
• 金额: $ 33.64万
• 依托单位: UNIVERSITY OF CENTRAL FLORIDA
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-01 至 2012-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7915429
• 关键词: Africa; Antibodies; Applications Grants; Bacillus anthracis; Bacteria; Bacterial Infections; Biological; Biological Assay; Biomedical Research; Blood; Blood specimen; Chemicals; Clinical; Crohn' s disease; Data; Detection; Diagnostic; Diagnostic tests; Drug resistance in tuberculosis; Enzyme-Linked Immunosorbent Assay; Escherichia coli EHEC; Escherichia coli O157; Food; Goals; Gold; Health Care Sector; Magnetism; Milk; Modeling; Molecular; Molecular Target; Monitor; Mycobacterium avium; Nature; Oligonucleotides; Paratuberculosis; Patients; Preparation; Principal Investigator; Proteins; Relaxation; Research; Ricin; Sampling; Signal Transduction; Specificity; Speed; System; Technology; Time; Toxin; United States; Viral Proteins; Water; Western Blotting; anthrax lethal factor; anthrax toxin; base; clinical decision-making; cost; detector; economic impact; edema factor; miniaturize; nanoparticle; nanoscale; nanosensors; nanoswitch; pathogen; point-of-care diagnostics; public health relevance; small molecule

DESCRIPTION (provided by applicant): Enabling diagnostic technologies that merge the use of nanoscale components and miniaturized detector systems could have a great impact in point-of -care diagnostics. In particular, diagnostic systems that are sensitive, robust, portable, low-cost, and can accurately quantify multiple molecular targets in parallel, would have a tremendous impact in biomedical research and molecular diagnostics. In this application, we propose to use a magnetic nanosensor technology, in conjunction with a portable magnetic relaxometer, to develop a sensitive diagnostic test for intracellular pathogens and toxins in clinical samples. Bacterial infections are on the rise in the United States and their economic impact on the healthcare sector is significant. The presence of enterohemorrhagic E. coli O157:H7 in tainted produce, the B. anthracis attacks in 2001, and the recent identification of drug resistant Mycobacterium tuberculosis have sparked public concern and underscore the need to develop sensitive and portable diagnostic technologies for fast and accurate detection of bacteria and toxins in food and clinical samples. Our approach utilizes "magnetic relaxation nanoswitches" (MRnS), i.e. magnetic nanoparticles that selectively change the spin-spin relaxation times (T2) of surrounding water molecules (NMR signal) upon specific molecular target interaction. The principal investigator of this grant application has previously shown that this technology can detect oligonucleotides in the femtomolemole range with extremely high molecular specificity [Nature Biotech. 2002;20:816-820], as well as other molecular targets such as proteins and viruses, without the need of target amplification. Most recently, we have developed magnetic nanosensors for the detection of a particular bacterium in blood and milk [Nanoletters 2007; 7, 380]. Also, with collaborators at the Army's Edgewood Chemical and Biological Center, we have gathered preliminary data to detect ricin toxin, using magnetic nanosensors. As a detector, we have used a newly developed minituarized and portable NMR relaxometer that allows substantial improvement in detection threshold and speed. The overall goal of this application is to extend research on magnetic nanosensors in an effort to develop highly sensitive, minituarized and portable detection systems to screen for the presence of a particular bacterium and toxin in clinical samples. We hypothesize that our magnetic nanoparticle system can provide a single homogeneous assay that can be used to detect the presence of intracellular pathogens and toxins in blood, without the need for target amplification. As an intracellular bacterial pathogen model, we will use Mycobacterium avium spp. paratuberculosis (MAP). As a toxin model, we will use anthrax toxin (AT), which is produced by another intracellular pathogen; B. anthracis. PUBLIC HEALTH RELEVANCE In this project, we will develop a diagnostic technology that merges the use of magnetic nanoparticles and a miniaturized detector to monitor the presence of an intracellular pathogen and toxin in clinical samples. This technology could facilitate quick, selective and sensitive bacterial detection to support clinical decision making.

描述（由申请人提供）：启用合并纳米级组件和微型探测器系统使用的诊断技术可能会对诊断的诊断产生重大影响。特别是，敏感，健壮，便携，低成本并且可以并行量化多个分子靶标的诊断系统对生物医学研究和分子诊断会产生巨大影响。在此应用中，我们建议将磁性纳米传感器技术与便携式磁性松弛计结合使用，以开发临床样品中细胞内病原体和毒素的敏感诊断测试。在美国，细菌感染正在增加，其对医疗保健部门的经济影响很大。在受污染的农产品中的肠内出血大肠杆菌O157：H7的存在，2001年的炭疽芽孢杆菌攻击以及最近鉴定出耐药性结核病结核病的鉴定，引发了公众的关注，并实现了敏感和可移植的诊断，以便开发出敏感和可移植的诊断，以便快速和准确地诊断出食物和造成糖果蛋白。我们的方法利用“磁弛豫纳米开关”（MRN），即在特定分子靶相互作用下选择性地改变周围水分子（NMR信号）的自旋旋转弛豫时间（T2）的磁性纳米颗粒。该赠款应用的主要研究者先前表明，该技术可以检测具有极高分子特异性的FEMTOMOLEMOLE范围内的寡核苷酸[Nature Biotech。 2002; 20：816-820]以及其他分子靶标，例如蛋白质和病毒，而无需靶标扩增。最近，我们开发了用于检测血液和牛奶中特定细菌的磁性纳米传感器[Nanoletters 2007; 7，380]。此外，在陆军Edgewood Chemical Chemical Center的合作者中，我们使用磁性纳米传感器收集了初步数据以检测Ricin毒素。作为检测器，我们使用了新开发的销售和便携式NMR松弛仪，可实质性地改善检测阈值和速度。该应用程序的总体目标是扩展对磁性纳米传感器的研究，以开发高度敏感，销售和便携式检测系统，以筛选临床样品中特定细菌和毒素的存在。我们假设我们的磁性纳米颗粒系统可以提供单个均质测定法，可用于检测血液中细胞内病原体和毒素的存在，而无需目标扩增。作为细胞内细菌病原体模型，我们将使用分枝杆菌鸟类属。旁结核病（地图）。作为毒素模型，我们将使用炭疽毒素（AT），该毒素是由另一种细胞内病原体产生的。 B.炭疽病。在该项目中，我们将开发一种诊断技术，该技术将磁性纳米颗粒和微型探测器的使用合并，以监测临床样品中细胞内病原体和毒素的存在。这项技术可以促进快速，选择性和敏感的细菌检测，以支持临床决策。