Thermal cross sections of hydrogels for NMR-driven neutron capture therapy

We propose a neutron experiment to establish and validate a quantitative procedure whereby information from nuclear magnetic resonance (NMR) spectroscopy and imaging is used to provide patient-specific neutron scattering libraries to be used to optimize transport codes in neutron capture therapy. In particular, using chemical shift spectra from 1H-NMR, the idea is to reconstruct the relative concentrations of organic functional groups in standard samples, and use these data to build the sample-specific macroscopic cross section at thermal neutron energies using the Average Functional Group Approximation. Therefore, we propose a neutron transmission measurement, taking advantage of the broad range of incident neutron energies available on the VESUVIO spectrometer, on a series of well-characterized hydrogel systems composed of semi-interpenetrated polymer networks (SIPN) to be suggested and used as standards for both neutron scattering and NMR standards.

我们提出一项中子实验，以建立并验证一套定量流程：借助核磁共振（Nuclear Magnetic Resonance, NMR）波谱与成像技术获取的信息，构建患者特异性中子散射库，用于优化中子俘获治疗中的输运程序。具体而言，我们将利用氢核磁共振（1H-NMR）的化学位移谱，重构标准样品中有机官能团的相对浓度，并基于这些数据，通过平均官能团近似（Average Functional Group Approximation）法，构建热中子能量下对应样品的宏观截面。据此，我们提议利用VESUVIO谱仪（VESUVIO Spectrometer）覆盖宽泛入射中子能量范围的优势，对一系列经过充分表征的半互穿聚合物网络（Semi-interpenetrated Polymer Networks, SIPN）基水凝胶体系开展中子透射测量，该体系可被推荐并用作中子散射与核磁共振的标准参照样品。