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https://doi.org/10.1002/9783527697281.ch10
NMR techniques are among the most influential analytical tools developed in the past century and widely used in various disciplines from oil well drilling to medicine. To date, two major hurdles inhibit an even more widespread use of NMR spectroscopy in science and society: first, NMR’s relatively low sensitivity severely constrains applications of mass- and volume-limited samples including lab-on-chip integration, in-cell analysis, and bioanalyte detection. Typical NMR samples contain micromole quantities of material in a relatively large sample volume of about 0.5ml; this large sample volume in turn imposes stringent requirements on the magnetic field – both for the generation but also on the susceptibility of the materials utilized in the probe head – which has to be homogenous in the whole sample volume with ppb resolution. Second, NMR equipment is very complex and costly. A major contribution to the high price of NMR equipment is constituted by the (cryogenic) superconducting magnets used to generate the static magnetic field.This problem will hopefully be tackled by the introduction of new magnet-manufacturing techniques and materials, for example, high-temperature superconductors, and the development of miniaturized spectrometers. Another complex and costly aspect concerns the heart of spectrometers consisting of intricate multifrequency probes, with coils integrated in sophisticated tuning–matching circuits connected to complex RF transceiver circuits. In viewof these limitations of currentNMRsystems, to make NMR more versatile and affordable, a key challenge is improving sensitivity and, at the same time, reducing cost and complexity of NMR probes and electronics.