BIOMEDICAL ACCELERATOR MASS SPECTROMETER FOR C14 AND H3

该计划的目标是开发一种专用的紧凑型加速器 质谱（AMS）系统，用于测量超低 标记的生物样品中的碳-14和氚的量。的 仪器的灵敏度至少要高出1000倍 通常使用的液体闪烁衰减计数器的，并将 为样本量的定量提供高测量精度 低至阿托摩尔水平。AMS的新方法将允许 加速器的能量大约降低三分之一 与现有的加速器质谱仪相比。这将大大 降低系统尺寸、成本和复杂性， 开发实验室规模的生物医学AMS仪器。的 在第一阶段中，已经证明了这种低能耗方法的可行性 实验表明，使用1 MV串联的AMS系统 加速器将允许明确检测14 C的浓度 降到当代样本中自然发生的水平。在第二阶段， 我们建议建造和测试一个低能量的AMS系统， 标记生物样品中14 C和3 H的检测。仪器 将使用一个紧凑的，1 MV串列加速器，并将设计为 与标准气相色谱仪接口。 拟议的商业应用：研究致癌作用的研究人员， 代谢和药物作用将大大受益于超敏感的 用于定量有机样品中14 C和氚的仪器。 在新药研究中，AMS灵敏度的提高将使人类 使用极少量的放射性示踪剂进行研究。 这种能力可以大大加快新药的测试。的 仪器的成本、尺寸和操作要求将 与主要研究中心的安装兼容。

The goal of this program is to develop a dedicated, compact accelerator mass spectrometry (AMS) system for the measurement of ultra-low quantities of carbon-14 and tritium in labeled biological samples. The instrument will have a sensitivity at least a factor-of-1000 higher than that of commonly-used liquid scintillation decay counters and will provide high measurement accuracy for the quantitation of sample sizes down to the attomole level. A new approach to AMS will allow the accelerator energy to be lowered by approximately a factor-of-three compared with existing accelerator mass spectrometers. This will greatly reduce system size, cost, and complexity and make possible the development of a laboratory-scale biomedical AMS instrument. The feasibility of this low-energy approach was demonstrated in the Phase I experiments which showed that an AMS system using a 1 MV tandem accelerator will allow the unambiguous detection of 14C at concentrations down to naturally occurring levels in contemporary samples. In Phase II, we propose to construct and test a low-energy AMS system optimized for the detection of 14C and 3H in labeled biological samples. The instrument will utilize a compact, 1 MV tandem accelerator and will be designed to interface with a standard gas chromatograph. PROPOSED COMMERCIAL APPLICATION: Researchers studying carcinogenesis, metabolism and drug effects will benefit greatly from an ultra-sensitive instrument for the quantitation of 14C and tritium in organic samples. In new drug research, the increased sensitivity of AMS will allow human studies to be performed using extremely small quantities of radiotracers. This capability could significantly speed the testing of new drugs. The cost, size, and operating requirements of the instrument will be compatible with installation at major research centers.