Abstract Radiopharmaceuticals used in nuclear medicine for therapy or diagnosis (molecular imaging, PETscan, scintigraphy) are characterized in terms of volume activity before injection to patients. The current measurement process relies on dose calibrators which have to be calibrated by transfer standards, traceable to primary standards. For very short half-life radionuclides (few minutes), the metrological traceability can only be assured through an on-site calibration with primary standards. However, until now, there is no primary system for the direct measurement of such high activity radioactive solutions. This study presents the sub-system under development for the measurement of a sampled volume of the order of 1 μL with an associated relative target standard uncertainty of 1%. The volume of solution is a key parameter in activity per unit of volume calibration of radiopharmaceuticals solutions. This article focuses on the volume measurement method development and its validation by comparison to the gravimetric method. The paper, in a first part, describes the developed method and the associated hardware and software. The authors have chosen a non-contact optical method implemented by a microscope camera and associated optics in front of a transparent capillary. The second part of the paper describes the measurement process. Several image processing steps are described and the traceability to dimensional units is presented. Finally, the paper presents some validation results by comparison to a gravimetric measurement, including repeatability and accuracy tests. Further development and improvements, necessary for the finalization of the prototype and the measurement of nano-flow rates are discussed.

中文翻译：

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开发用于“采样”微体积和纳米流速的光学测量方法

摘要 核医学中用于治疗或诊断（分子成像、PET 扫描、闪烁扫描）的放射性药物的特征在于注射给患者之前的体积活性。当前的测量过程依赖于剂量校准器，这些校准器必须通过传输标准进行校准，可追溯到主要标准。对于半衰期非常短（几分钟）的放射性核素，只能通过使用一级标准进行现场校准来确保计量溯源性。然而，直到现在，还没有用于直接测量这种高活性放射性溶液的主要系统。本研究介绍了正在开发的子系统，用于测量 1 μL 数量级的采样体积，相关的相对目标标准不确定度为 1%。溶液体积是放射性药物溶液每单位体积校准活性的关键参数。本文重点介绍体积测量方法的开发及其与重量法的比较。该论文的第一部分描述了所开发的方法以及相关的硬件和软件。作者选择了一种非接触式光学方法，由显微镜相机和透明毛细管前面的相关光学器件实现。论文的第二部分描述了测量过程。描述了几个图像处理步骤，并介绍了对尺寸单位的可追溯性。最后，本文通过与重量测量进行比较，展示了一些验证结果，包括重复性和准确性测试。进一步的发展和改进，