Theoretical studies of physical and chemical aspects of primary processes in fundamental radiobiology

基础放射生物学初级过程的物理和化学方面的理论研究

• 批准号: RGPIN-2015-06100
• 负责人: JayGerin, JeanPaul
• 金额: $ 3.35万
• 依托单位: Université de Sherbrooke
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=654555
• 关键词: Theoretical; studies; physical; chemical; aspects

An understanding of radiation-induced processes in aqueous systems is vital to many areas of basic and applied radiobiological physics and chemistry, medicine, and in a variety of technological and industrial applications. If, nowadays, a general understanding of the phenomena that underline the radiation chemistry of water and aqueous solutions has been obtained in many cases, it appears that certain quantitative aspects of this radiolysis are not yet fully resolved. This is especially true forultrafast processes that link chemistry and physics in the first few picoseconds following energy deposition. Understanding this interface between radiation physics and radiation chemistry (i.e., "breaking the picosecond barrier") is of obvious relevance to fundamental radiobiology and related science as liquid water is by far the most abundant constituent of biological cells and tissue (living cells contain ~70-85% water by weight). Most importantly, it is central to a reliable description of the chemical nature and highly nonhomogeneous spatial distribution of all reactive species created on the (sub) picosecond time scale and involved as precursors of radiobiological damage. This understanding is also critical to creating reliable predictive models. Of a theoretical nature, the present project will focus on the characterization of the physicochemical stage of radiation action (. In particular, one difficult problem that we wish to address in the next five years under an NSERC Discovery Grant is the physical behavior of the numerous low-energy (experiment-and-theory based models to advance our knowledge of the radiolysis of (dilute and concentrated) aqueous systems for which, we feel, an early-time, molecular-level characterization of the underlying chemistry is essential to produce a complete, accurate picture of this radiolysis. It is, without doubt, part of a major challenge in fundamental radiobiology where our long-term goal is to achieve a global comprehension of the effects of radiation in biological systems and to apply this knowledge to enhance the therapeutic and diagnostic efficiency of radiation.

对水体系中辐射诱导过程的了解对于基础和应用放射生物学物理、化学、医学以及各种技术和工业应用的许多领域都是至关重要的。如今，如果在许多情况下，人们已经对水和水溶液的辐射化学现象有了普遍的了解，那么这种辐射分解的某些定量方面似乎还没有完全解决。对于在能量沉积后的最初几皮秒内将化学和物理联系起来的超快过程尤其如此。理解辐射物理和辐射化学之间的这种界面(即“打破皮秒屏障”)与基础放射生物学和相关科学具有明显的相关性，因为液态水是迄今为止生物细胞和组织中含量最丰富的成分(活细胞含有约70%-85%的水的重量)。最重要的是，它对于可靠地描述化学性质和在(亚)皮秒时间尺度上产生的所有活性物种的高度不均匀的空间分布是至关重要的，这些活性物种作为放射生物损害的前兆参与其中。这一理解对于创建可靠的预测模型也至关重要。在理论性质上，本项目将专注于辐射作用的物理化学阶段的表征(尤其是，我们希望在未来五年内根据NSERC发现拨款解决的一个难题)是众多低能(基于实验和理论的)模型的物理行为，以促进我们对(稀释和浓缩的)水体系辐射分解的深入了解，我们认为，对于这些模型，对基础化学的早期、分子水平的表征对于产生这种辐射分解的完整、准确的图像至关重要。毫无疑问，这是基础放射生物学中一项重大挑战的一部分，我们的长期目标是实现对辐射在生物系统中的影响的全球理解，并应用这一知识来提高辐射的治疗和诊断效率。