DENDRITIC OXYGEN SENSOR WITH TWO-PHOTON ABSORBING ANTENNA

带双光子吸收天线的树枝状氧传感器

• 批准号: 7955437
• 负责人: SERGEI VINOGRADOV
• 金额: $ 1.92万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-06-01 至 2010-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7955437
• 关键词: Biological; Complex; Computer Retrieval of Information on Scientific Projects Database; Coupling; Dorsal; Dyes; Electron Transport; Energy Transfer; Exhibits; Fluorescence; Funding; Grant; Image; Imaging Techniques; Institution; Laboratories; Laser Scanning Microscopy; Lasers; Link; Measures; Methods; Microscope; Microscopic; Modeling; Molecular; Optics; Oxygen; Pd-porphyrin; Play; Porphyrins; Process; Rattus; Research; Research Personnel; Resolution; Resources; Role; Sapphire; Scanning; Signal Transduction; Source; Surface; System; Techniques; Testing; Time; Tissues; Triplet Multiple Birth; United States National Institutes of Health; absorption; base; chromophore; in vivo; phosphorescence; prevent; sensor; single molecule; submicron; tumor; two-photon

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Imaging oxygen in 3D with sub-micron spatial resolution can be made possible by combining phosphorescence quenching technique with multiphoton laser scanning microscopy. However, Pt and Pd porphyrin-based phosphorescent dyes, traditionally used as phosphors in biological oxygen sensing, exhibit extremely low two-photon absorption (2PA) cross-sections. Using chromophors with large known two photon cross sections linked to porphyrins, we are investigating the possibility of generating high phosphorescence yields after photoexcitation and subsequent energy transfer between chormophor and porphyrin. Such complexes would be highly desirable for single molecule (SM) studies employing phosphorescence instead of fluorescence. Up to this point, the use of phosphorescence is quite limited in SM techniques due to the low level of signal. Oxygen dependent quenching of phosphorescence is a sensitive method for measuring molecular oxygen. Our proposed complexes could play a key role in measuring molecular oxygen in tissue employing an imaging technique in vivo. Specific aims of our project include: (1) Synthesize 2P absorbing phosphorescent probes, in which 2P antenna dyes are separated from the triplet emitter by a dendritic "insulator," to prevent intamolecular quenching of the phosphorescence via electron transfer. (2) Modify the existing confocal microscope system by coupling it with a femtosecond Ti:Sapphire laser and a time domain phosphorometer to perform 2P excitation of antenna chromophores, scanning the object in axial planes under the surface and measuring phosphorescence lifetimes. (3) Align and test the entire setup using an appropriate model with microscopic oxygen gradients. Validate the technique by performing in vivo oxygen imaging in the dorsal window tumor model in rats.

该副本是利用众多研究子项目之一 由NIH/NCRR资助的中心赠款提供的资源。子弹和 调查员（PI）可能已经从其他NIH来源获得了主要资金， 因此可以在其他清晰的条目中代表。列出的机构是 对于中心，这不一定是调查员的机构。 通过将磷光淬灭技术与多光子激光扫描显微镜相结合，可以通过亚微米空间分辨率在3D中成像氧。 然而，传统上用作生物氧气传统的磷脂的PT和PD卟啉染料表现出极低的两光子吸收（2PA）横截面。 使用具有与卟啉有关的大型已知两个光子横截面的发色粒，我们正在研究光激发后产生高磷光产量的可能性，以及直流和卟啉之间的随后能量转移。对于使用磷光而不是荧光的单分子（SM）研究，这种复合物将是非常可取的。到目前为止，由于信号水平较低，磷光技术的使用非常有限。 磷光依赖氧的淬灭是一种测量分子氧的灵敏方法。我们提出的配合物可以在测量体内成像技术的组织中测量分子氧中起关键作用。 我们项目的具体目标包括： （1）合成2p吸收磷光探针，其中2p天线染料通过树突“绝缘子”与三重态发射器分离，以防止通过电子转移对磷酸化的内分分子淬火。 （2）通过将其与飞秒ti结合到现有的共聚焦显微镜系统：蓝宝石激光器和时域磷光计对天线发色子团的2P激发，从而在表面下的轴向平面扫描对象并测量磷光寿命。 （3）使用适当的模型与微观氧梯度对齐并测试整个设置。 通过在大鼠背窗肿瘤模型中进行体内氧成像来验证该技术。