NanoSPINs for In Vivo EPR-Based Spectroscopy and Imaging

用于基于 EPR 的体内光谱和成像的 NanoSPIN

• 批准号: 7923988
• 负责人: Valery V Khramtsov
• 金额: $ 39.64万
• 依托单位: OHIO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-01 至 2011-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7923988
• 关键词: Acidity; Acidosis; Animals; Ascorbic Acid; Biochemical Process; Biological; Biological Preservation; Cell Membrane Permeability; Characteristics; Chemicals; Data; Detection; Development; Drug Stability; Electron Spin Resonance Spectroscopy; Ensure; Environment; Fluorescence; Fluorescent Probes; Future; Gel; Generations; Glass; Goals; Heart; Human; Image; Infusion procedures; Injury; Ions; Ischemia; Ischemic Preconditioning; Journals; Life; Lipids; Liposomes; Measurement; Measures; Medicine; Methods; Modeling; Molecular Probes; Monitor; Mus; Myocardial; Myocardial Ischemia; Myocardium; Nitric Oxide; Oxidation-Reduction; Peer Review; Penetration; Perfusion; Permeability; Phase; Phospholipids; Play; Preparation; Procedures; Production; Publications; Publishing; Rattus; Reducing Agents; Reperfusion Injury; Reperfusion Therapy; Role; Signal Transduction; Specificity; Spectrum Analysis; Techniques; Testing; Therapeutic; Time; Tissues; Variant; Vesicle; base; bioimaging; design; gramicidin A; in vivo; mouse model; nanoparticle; nanosized; novel strategies; pH Homeostasis; particle; photonics; preconditioning; prevent; public health relevance; research study; sensor; spectroscopic imaging; success; technique development

DESCRIPTION (provided by applicant): This project will develop a new generation of paramagnetic, functionally oriented probes for the needs of electron paramagnetic resonance (EPR) spectroscopy and imaging, particularly for in vivo applications. EPR- based techniques are far from attaining their maximum potential, predominantly because of a lack of stable in vivo exogenous spin probes available. All the advantages of application of wide classes of nitroxide probes to biomedicine are largely wiped out by their rapid degradation in tissues to EPR-silent products. In this project several new approaches will be used to develop paramagnetic probes with increased in vivo stability based on the original idea of the construction of the nano-Sized Particles with the Incorporated Nitroxides, or nanoSPINs. These nanoSPINs, being permeable to small analytes will separate sensing nitroxides from biological reductants. The nanoSPIN sensors will be used to detect physiologically important species, namely H+ (pH) and nitric oxide (NO). This will fill a niche between fluorescent probes, which have advanced our detection capabilities at cellular and subcellular levels, and NMR/MRI, which have provided spectroscopic and imaging capabilities in intact living animals and humans. However, NMR/MRI suffers from the lack of sensitivity (1000 fold or lower than EPR) and specificity. The specific aims are: (SA1) Development of effective methods for the nanoSPIN design. The proposed strategies are based on two matrixes for nitroxide encapsulation, sol gel "glasses" and phospholipid bilayer vesicles, including use of polymerized liposomes. The small ion permeability of the liposomes will be ensured by incorporation of "pore formers" such as gramicidin A. (SA2) Physicochemical characterization of pH- and NO-sensitive nanoSPINs. Quantitative characterization of the nanoSPINs, particularly functional sensitivity and stability in biological tissues, is absolutely crucial, both for the optimization of the preparation procedures and for efficiency of their applications. (SA3) To study the role of myocardial acidosis and NO generation in ischemic hearts and in the model of ischemic preconditioning using developed nanoSPINs. We hypothesize that alterations in pH homeostasis and NO production play critically important roles in ischemic preconditioning (IPC). To test the hypothesis, myocardium acidosis and NO production will be monitored noninvasively by EPR in ischemic control and preconditioned hearts. (SA4) To apply in vivo EPR measurements of pH and NO generation in models of mouse heart regional ischemia reperfusion with ischemic preconditioning. In order to test our pH and NO hypothesis in IPC, we will use this in vivo mouse heart model to noninvasively monitor the variations of myocardial pH and NO generation and their correlations to the protective mechanisms of IPC using developed nanoSPINs. The results may provide an opportunity for the design of corresponding therapeutic approaches. In summary, the success of this project may have a significant impact on the future of in vivo EPR spectroscopy and bioimaging applications to medicine. PUBLIC HEALTH RELEVANCE: This project will develop a new generation of paramagnetic functionally oriented probes, termed nanoSPINs, for the needs of electron paramagnetic resonance (EPR) spectroscopy and bioimaging, particularly for in vivo applications to medicine. Application experiments will use pH- and NO-sensitive nanoSPINs in isolated rat hearts and in vivo in a {models of mouse heart regional ischemia reperfusion with ischemic preconditioning} and will provide new opportunities for designing corresponding therapeutic approaches.

描述（由申请人提供）：该项目将开发新一代的顺磁性，功能性探针，以满足电子顺磁共振（EPR）光谱和成像的需求，尤其是对于体内应用。基于EPR的技术远未达到其最大潜力，主要是因为可用的体内外源性旋转探针缺乏稳定。将广泛的氮氧化物探针应用于生物医学的所有优势在很大程度上通过组织在组织中的快速降解为EPR-siplent产品所取代。在该项目中，基于与纳米氧化物或纳米辛的纳米尺寸颗粒构建的最初想法，将使用几种新方法来开发具有体内稳定性的顺磁性探针。这些纳米替代物可以渗透到小分析物中，将把硝基氧化物与生物还原剂分开。 Nanospin传感器将用于检测生理上重要的物种，即H+（pH）和一氧化氮（NO）。这将填充荧光探针之间的利基市场，这些探针在细胞和亚细胞水平上提高了我们的检测能力，以及NMR/MRI，这些功能在完整的活体动物和人类中提供了光谱和成像能力。但是，NMR/MRI缺乏灵敏度（1000倍或低于EPR）和特异性。具体目的是：（SA1）开发纳米平设计的有效方法。提出的策略基于两个用于氮氧化物封装的基质，溶胶凝胶“玻璃”和磷脂双层囊泡，包括使用聚合脂质体。脂质体的小离子渗透性将通过掺入诸如gramicidin A.（SA2）pH-和无敏感纳米替代的理化表征的“孔形成”（SA2）。纳米辛的定量表征，尤其是生物组织中的功能敏感性和稳定性，对于优化制备程序和应用效率而言都是至关重要的。 （SA3）研究心肌酸中毒和在缺血性心脏中没有产生的作用，以及使用已发达纳米辛的缺血性预处理模型。我们假设pH稳态的改变和没有生产在缺血性预处理（IPC）中起着至关重要的作用。为了检验该假设，EPR在缺血性控制和预处理心脏中无创的酸中毒和无生产的监测。 （SA4）在小鼠心脏区域缺血再灌注模型中使用pH和无产生的体内EPR测量，并使用缺血性预处理。为了测试我们的pH值，在IPC中没有假设，我们将使用此体内小鼠心脏模型来非侵入性地监测心肌pH值的变化，而无产生及其与IPC的保护机制的相关性使用已发达的Nanospins。结果可能为设计相应的治疗方法设计提供了机会。总之，该项目的成功可能会对体内EPR光谱和医学生物成像应用的未来产生重大影响。 公共卫生相关性：该项目将开发新一代的顺磁性功能探针，称为纳米辛，以满足电子顺磁共振（EPR）光谱和生物成像的需求，尤其是对于体内医学应用。应用实验将在孤立的大鼠心脏和体内使用pH含量和无敏感的纳米辛，并在{小鼠心脏区域缺血模型中进行缺血预处理}，并将为设计相应的治疗方法提供新的机会。