Structural shimming for high-resolution nuclear magnetic resonance spectroscopy in lab-on-a-chip devices.
Structural shimming for high-resolution nuclear magnetic resonance spectroscopy in lab-on-a-chip devices.
复制标题
芯片实验室设备中高分辨率核磁共振波谱的结构匀场。
DOI：
10.1039/c3lc51431e
复制
发表时间：
2014
期刊：
影响因子：
6.1
通讯作者：
Utz,Marcel
中科院分区：
文献类型：
--
作者：
Ryan,Herbert;Smith,Alison;Utz,Marcel
高分辨率质子NMR光谱学是公认的用于宏观尺度上的生物流体的代谢组学分析的工具。然而，在微流体装置的背景下，其全部潜力尚未实现。虽然微制造的NMR检测器在灵敏度方面提供了实质性的增益，但是由样品流体和芯片材料的磁化率的不匹配导致的有限的光谱分辨率仍然是一个主要障碍。在这方面的贡献，我们表明，即使在存在大量的不匹配，包括适当形状的补偿结构到芯片设计中，可以避免磁化率展宽。一个有效的算法，用于计算从任意芯片布局的场图高斯正交的基础上，用于优化补偿结构的形状，以确保一个平坦的场分布内的样品区域。以前，微流体NMR系统的复杂性已被限制为简单的毛细管，以避免敏感性加宽。这里介绍的结构匀场方法可以适用于几乎任何形状的样品室和周围的流体网络，从而大大扩展了设计空间，并实现了真正的适合高分辨率NMR检测的芯片实验室系统。
High-resolution proton NMR spectroscopy is well-established as a tool for metabolomic analysis of biological fluids at the macro scale. Its full potential has, however, not been realised yet in the context of microfluidic devices. While microfabricated NMR detectors offer substantial gains in sensitivity, limited spectral resolution resulting from mismatches in the magnetic susceptibility of the sample fluid and the chip material remains a major hurdle. In this contribution, we show that susceptibility broadening can be avoided even in the presence of substantial mismatch by including suitably shaped compensation structures into the chip design. An efficient algorithm for the calculation of field maps from arbitrary chip layouts based on Gaussian quadrature is used to optimise the shape of the compensation structure to ensure a flat field distribution inside the sample area. Previously, the complexity of microfluidic NMR systems has been restricted to simple capillaries to avoid susceptibility broadening. The structural shimming approach introduced here can be adapted to virtually any shape of sample chamber and surrounding fluidic network, thereby greatly expanding the design space and enabling true lab-on-a-chip systems suitable for high-resolution NMR detection.