SBIR Phase I: Boron Nitride Nanotube Cyclotron Targets for Recoil-Escape Production of Carbon-11 For PET/CT

这项小企业创新研究（SBIR）第一阶段项目的更广泛影响/商业潜力是满足低成本按需生产碳-11的需求，用于核医学中生物标志物和放射性示踪剂的应用。生物标志物和放射性示踪剂通常用于代谢成像，以支持研究，药物发现以及癌症和其他疾病的检测。它们也用于癌症的治疗分期，以确定治疗是否有效。常见的例子包括心脏的心肌灌注成像，以显示血液流动和功能，正电子发射断层扫描（PET）扫描大脑，以检测早期发病的阿尔茨海默氏症和脑肿瘤，以及用于诊断和分期前列腺癌的胆碱正电子发射断层扫描-计算机断层扫描（PET/CT）。碳-11是一种重要的放射性示踪剂/放射性药物，它具有独特的优势，因为它能够很容易地结合到许多分子中而不影响生物活性。目前，碳-11是通过在高能商业回旋加速器上使用专门的目标来产生的。这些回旋加速器的安装成本高达数百万美元，而且现有的目标效率低下。低能量回旋加速器的成本要低得多，目前正由多家商业公司开发。该项目旨在开发一种新的回旋加速器目标方法，用于使用独特的纳米材料以低能量生产碳-11，从而显著降低成本。这个项目的智力价值包括使用新型纳米材料，通过开发后坐力逃逸目标，更有效地以更低的成本生产碳-11。找到一种好的目标材料，既能通过几种可用的核反应之一有效地产生碳-11，又能以可用的形式有效地回收所产生的放射性示踪剂，这是一项挑战。产生的碳-11很难回收，因为它很容易被困在许多传统的目标材料中，导致产量低。纳米科学和技术的最新进展使生产具有独特特性的新材料成为可能。氮化硼纳米管（BNNT）由单原子厚度或最多几个原子厚度的纤维组成，允许碳-11有效地产生，并使用低能回旋加速器以二氧化碳气体的形式回收。该项目旨在进一步开发具有理想特性的BNNT材料，包括高纯度和最佳密度。将开发和测试一个原型生产目标，该目标可用于使用经济，低能量回旋加速器生产碳-11。收集碳-11气体的过程将得到优化，以实现可用放射性示踪材料的最高产量。

The broader impact/commercial potential of this Small Business Innovation Research (SBIR) Phase I project is to meet the need for low cost dose-on-demand production of Carbon-11 for biomarker and radiotracer applications in nuclear medicine. Biomarkers and radiotracers are commonly used for metabolic imaging, in support of research, drug discovery, and detection of cancer and other illnesses. They are also used for therapy staging of cancer, to determine if treatment is effective. Common examples include myocardial perfusion imaging of the heart to visualize blood flow and function, positron emission tomography (PET) scanning of the brain to detect early onset Alzheimer's and brain tumors, and Choline positron emission tomography - computed tomography (PET/CT) for the diagnosis and staging of prostate cancer. Carbon-11 is an important radiotracer/radiopharmaceutical that offers unique advantages due to its ability to be easily incorporated into many molecules without impacting biological activity. Carbon-11 is currently produced by using specialized targets on high-energy commercial cyclotrons. These cyclotrons cost millions of dollars to install and existing targets are inefficient. Low energy cyclotrons are significantly less expensive, and are currently under development by multiple commercial companies. This project seeks to develop a novel cyclotron target methodology for producing Carbon-11 at low energies using unique nanomaterials, resulting in significantly lower costs. The intellectual merit of this project involves the use of novel nanomaterials to produce Carbon-11 more efficiently and at lower cost, through development of recoil escape targets. It is challenging to find a good target material suitable for both efficient production of Carbon-11, by one of several available nuclear reactions, and efficient recovery of the produced radiotracer in a usable form. The produced Carbon-11 can be difficult to recover, as it is easily trapped in many conventional target materials, resulting in low yields. Recent advances in nanoscience and technology allow for production of novel materials with unique characteristics. Boron nitride nanotubes (BNNT) are composed of fibers with single atomic thickness, or at most a few atoms thick, allowing Carbon-11 to be efficiently produced and recovered in the form of carbon dioxide gas using low energy cyclotrons. This project seeks to further develop BNNT materials with ideal characteristics, including high purity and optimal density. A prototype production target will be developed and tested which can be used to produce Carbon-11 using economical, low-energy cyclotrons. The process for collecting the Carbon-11 gas will be optimized to achieve the highest yields of usable radiotracer material.