Regensburg 2019 – wissenschaftliches Programm
CPP 25.20: Poster
Dienstag, 2. April 2019, 14:00–16:00, Poster B1
NMR investigations of microfluidics using stripline geometry — •Raoul Nitzsche, Benjamin Kresse, Alexei F. Privalov, and Michael Vogel — TU Darmstadt, Institut für Festkörperphysik, Hochschulstr. 6, 64289, Darmstadt, Germany
NMR spectroscopy with microfluidic devices puts high requirements on the probeheads sensitivity. Due to small sample volumes in the µ l range, common high frequency (HF) coils of typically 5 to 10 mm cannot be completely filled. A solution to this problem is the stripline, a component commonly used in HF-technique. A flat wire instead of a coil produces the RF pulse in the NMR experiment and detects the signal. This design allows a high filling factor and a homogeneous RF field for signal enhancement and, thus, also a high time resolution. It enables a lab-on-a-chip implementation which is a simple and effective design to examine small amounts of liquids. The stripline is successfully implemented in NMR spectroscopy using microchannels by the Kentgens group . Our test experiments revealed an increased signal-to-noise ratio and a good spectral resolution, as required to distinguish different molecular species with sufficient time resolution. Our goal is to follow the mixing process of two liquids by recording images in a static field gradient spectrometer. For this purpose, we implemented a Y-shaped microfluidic device in a stripline to control the mixing. This design enables the possibility to monitor chemical reactions in a standard cryomagnet.
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