A generic approach is presented that allows high-resolution NMR spectroscopy of water/oil droplet emulsions in microfluidic devices. Microfluidic NMR spectroscopy has recently made significant advances due to the design of micro-detector systems and their successful integration with microfluidic devices. Obtaining NMR spectra of droplet suspensions, however, is complicated by the inevitable differences in magnetic susceptibility between the chip material, the continuous phase, and the droplet phases. This leads to broadening of the NMR resonance lines and results in loss of spectral resolution. We have mitigated the susceptibility difference between the continuous (oil) phase and the chip material by incorporating appropriately designed air-filled structures into the chip. The susceptibilities of the continuous and droplet (aqueous) phases have been matched by doping the droplet phase with a Eu³⁺ complex. Our results demonstrate that this leads to a proton line width in the droplet phase of about 3 Hz, enabling high-resolution NMR techniques.

中文翻译：

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微流控液滴中的高分辨率核磁共振波谱

提出了一种通用方法，该方法可以对微流控设备中的水/油滴乳液进行高分辨率NMR光谱分析。由于微检测器系统的设计及其与微流体设备的成功集成，微流体NMR光谱学最近取得了重大进展。然而，由于芯片材料，连续相和液滴相之间不可避免的磁化率差异，获得液滴悬浮液的NMR光谱变得很复杂。这导致NMR共振线变宽并导致光谱分辨率的损失。通过将适当设计的充气结构结合到芯片中，我们缓解了连续（油）相与芯片材料之间的磁化率差异。³⁺复杂。我们的结果表明，这导致液滴相中的质子线宽度约为3 Hz，从而启用了高分辨率NMR技术。