Untuned broadband spiral micro-coils achieve sensitive multi-nuclear NMR TX/RX from microfluidic samples
Document Type
Article
Publication Date
4-8-2021
Abstract
The low frequency plateau in the frequency response of an untuned micro-resonator permits broadband radio-frequency reception, albeit at the expense of optimal signal-to-noise ratio for a particular nucleus. In this contribution we determine useful figures of merit for broadband microcoils, and thereby explore the parametric design space towards acceptable simultaneous excitation and reception of a microfluidic sample over a wide frequency band ranging from C-13 to H-1, i.e., 125-500 MHz in an 11.74 T magnet. The detector achieves 37% of the performance of a comparably sized, tuned and matched resonator, and a linewidth of 17 ppb using standard magnet shims. The use of broadband detectors circumvents numerous difficulties introduced by multi-resonant RF detector circuits, including sample loading effects on matching, channel isolation, and field distortion.
Keywords
Nuclear-magnetic-resonance, C-13 NMR, Dimensional structure, Spectroscopy
Divisions
CHEMISTRY
Funders
European Commission,Tokyo Metropolitan University for the Promotion of Joint International Research,Karlsruhe Nano Micro Facility (KNMF),Helmholtz Research Infrastructure at Karlsruhe Institute of Technology,Helmholtz Research Area Information, Materials Systems Engineering, Topic 5 Materials Information Discovery at the Karlsruhe Institute of Technology (KIT)
Publication Title
Scientific Reports
Volume
11
Issue
1
Publisher
Nature Research
Publisher Location
HEIDELBERGER PLATZ 3, BERLIN, 14197, GERMANY