Performance highlights of MARVEL NMR probes
Introduction
Conventional liquid‑state NMR probes are typically built in one of two configurations: direct or inverse/indirect detection. In a direct probe, the innermost and most sensitive coil is tuned to an X‑nucleus (such as 31P, 13C, 15N), while the outer coil is tuned to 1H. In an inverse probe, the inner coil is tuned to 1H and/or to 19F, and the outer coil is tuned to X. Direct probes provide excellent X‑nucleus sensitivity with moderate 1H/19F performance, whereas inverse probes deliver outstanding 1H/19F sensitivity with moderate X‑channel sensitivity. Historically, spectroscopists have had to choose between these two designs based on the requirements of each experiment.
The JEOL SuperCOOL MARVEL probe introduces a new approach. This liquid‑nitrogen‑cooled, two‑channel probe features a high‑frequency (HF) channel that can be tuned to either 1H or 19F, and an X‑channel that covers nuclei resonating at frequencies of 31P and below. The result is a single probe that delivers exceptional sensitivity for both high‑ band and low‑ band nuclei.
This note highlights several key aspects of the SuperCOOL MARVEL probe’s performance that are central to modern NMR spectroscopy, including its sensitivity across multiple nuclei, its robust RF power‑handling capabilities, and its versatility in experiments involving 1H, 19F, and X‑nuclei.