Since the subject of nuclear magnetic resonance (NMR) was awarded its first Nobel Prize in 1952 due to its successful detection by Bloch and Purcell in 1945, the technology and its applications have developed tremendously. The first two decades were focused on technical developments of instrumentation and methodologies to apply to the structure determination of compounds. During the late 1970s, several research groups developed modifications of NMR probes to convert them to an online mode for the analysis of sample mixtures