Pb-Qdot Direct Gamma Detectors

Pb-Qdot 直接伽马探测器

基本信息

批准号：
7613016
负责人：
Irving Weinberg
金额：
$ 19.99万
依托单位：
WEINBERG MEDICAL PHYSICS, LLC
依托单位国家：
美国
项目类别：
财政年份：
2008
资助国家：
美国
起止时间：
2008-09-29 至 2010-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7613016
关键词：
Address Advertising American Automobile Driving Beds Behavior Breast Bromides Cadmium Characteristics Charge Childhood Clinical Clinical Trials Communities Competence Cost Analysis Cost Savings Counseling Count DCNU Data Depth Detection Development Devices Diagnostic Equipment Diagnostic Imaging Diagnostic radiologic examination Digital Radiography Disadvantaged Discipline of Nuclear Medicine Dose Drug Formulations Economics Electronics Electrons Equipment Evaluation Event Exhibits Exposure to Extravasation Facility Construction Funding Category Film Funding Gadolinium Gamma Cameras Gamma Rays Goals Government Grant Hand Hardness Health Benefit Hour Image Imaging Device Institutes Institution Intellectual Property International Internet Invasive Investments Knowledge Lanthanum Lead Legal patent Length Licensing Life Los Angeles Love Lutetium Lymphatic System Magnetic Resonance Imaging Maintenance Manufacturer Name Marketing Medical Medical Imaging Methods Nanotechnology Numbers Organ Other Imaging Modalities PET/CT scan Patients Performance Persons Phase Physics Physiologic pulse Plastics Polymers Population Positioning Attribute Positron-Emission Tomography Press Releases Price Procedures Process Property Prostate Public Health Pulse taking Purpose Quality Control Quantum Dots Radiation Research Research Personnel Resolution Resources Risk Roentgen Rays Sales Salts Selenium Semiconductors Signal Transduction Silicon Simulate Solid Solutions Standards of Weights and Measures Structure Surveys Suspension substance Suspensions System Technology Testing Thick Time Translating United States United States National Institutes of Health Vendor Visible Radiation Work Zinc absorption attenuation base cadmium telluride cancer cell cancer diagnosis commercialization cost design design and construction detector discount electron density experience improved infancy innovation interest lead selenide lead sulfide magnetic field millimeter molecular imaging nanomaterials nanoparticle nanoscale novel pre-clinical prototype quantum radiation detector retinal rods sensor size solid state tool voltage

项目摘要

DESCRIPTION (provided by applicant): Molecular imaging systems (e.g., PET, gamma cameras) require electron-dense materials to effectively detect high-energy gamma rays. The traditional solution to increasing electron density in detectors has been to fabricate scintillators out of high-atomic-number materials (e.g., lanthanum bromide). High quality electron-dense scintillators tend to be expensive, due to difficulties in delivering crystal boules of high transparency and uniformity. Scintillators also have the disadvantage of requiring photodetectors (e.g., photomultipliers) to convert visible light into electrical signals, further adding to bulk and expense. Direct-detecting solid-state devices have better energy resolution than scintillators because of the reduced number of steps in the conversion process from gamma-rays to electrical signal. Several solid-state materials are available with excellent energy resolutions (e.g., CZT - cadmium zinc telluride), but have low stopping power for gamma-rays used in PET systems, and are relatively expensive. Although other semiconducting electron-dense compounds are available with high stopping power (i.e. PbS, PbSe), it has been challenging to design direct-detecting devices using them, because of unfavorable electronic properties of these compounds (e.g., low carrier mobility- lifetime product and/or narrow band-gap). Low carrier mobility-lifetime product results in poor energy resolution for detector of any practical thickness. Narrow band-gaps result in low resistivity, and consequently in high leakage current. Nanotechnology can provide confined materials (e.g., quantum dots) with electronic properties that significantly differ from those of the bulk formulations of the same compounds. This ability to fine-tune electronic properties has generated strong interest within the photovoltaic community. This proposal builds on the substantial work generated by one group that has embedded quantum structures in semiconducting plastics, forming conducting polymer donor- acceptor bulk heterojunctions with favorable mobility-lifetime and band-gap characteristics. Fortuitously from our point of view, quantum dots can be constructed of inexpensive compounds with high atomic number (e.g., lead sulfide). We propose to explore the use of inexpensive electron-dense quantum dot/polymer composites as x-ray and gamma-ray detectors. PUBLIC HEALTH RELEVANCE: Molecular imaging systems (PET and nuclear medicine) have become integrated into cancer diagnosis and treatment. These molecular imaging systems employ expensive detector materials in order to efficiently collect radiation. We propose the use of nanotechnology methods to fabricate novel radiation detector materials that will reduce cost and size of molecular imaging systems, and lower patients' radiation exposures.

描述（由申请人提供）：分子成像系统（例如PET，伽马相机）需要电子密集的材料以有效检测高能量γ射线。探测器中电子密度增加的传统解决方案是用高原子数材料（例如，兰植物溴化物）制造闪烁体。高质量的电子致密闪烁体往往很昂贵，这是因为在交付高透明度和均匀性的晶体boules方面遇到了困难。闪烁体还具有要求光电探测器（例如，光电倍增器）将可见光转换为电信号的缺点，进一步增加了批量和费用。直接检测固态设备的能量分辨率比闪烁器具有更好的能量分辨率，因为从伽马射线到电信号的转换过程中的步骤数量减少。有几种固态材料具有出色的能源分辨率（例如CZT-CADMIUM锌柜），但在宠物系统中使用的伽马射线的停止功率较低，并且相对昂贵。尽管其他半导体电子致密化合物具有高阻止功率（即PBS，PBSE），但由于这些化合物的电子性能不佳（例如，低载体移动性 - 生命周期产品 - 生命周期产品和/或狭窄的频道），使用它们的直接检测设备设计直接检测设备一直是一项挑战。低载体迁移率少量产物导致任何实用厚度的检测器的能量分辨率差。狭窄的带隙导致电阻率低，因此在高泄漏电流中。纳米技术可以提供与相同化合物的大量制剂明显不同的电子特性提供的限制材料（例如量子点）。这种微调电子特性的能力在光伏社区中引起了浓厚的兴趣。该建议建立在一个将量子结构嵌入半导体塑料中的一组产生的实质性工作，形成了具有有利的余余体和带隙特征的指导聚合物供体散装散装异质界。从我们的角度来看，毫无疑问，量子点可以由具有高原子数的廉价化合物（例如，硫化物）构建。我们建议探索廉价的电子致密量子点/聚合物复合材料作为X射线和伽马射线检测器的使用。公共卫生相关性：分子成像系统（PET和核医学）已纳入癌症诊断和治疗。这些分子成像系统采用昂贵的探测器材料来有效收集辐射。我们建议使用纳米技术方法来制造新型的辐射探测器材料，以降低分子成像系统的成本和大小，并降低患者的辐射暴露。