LC-NMR Solvents


Although an efficient separation method is available by HPLC, no structure determination is possible when detecting separated compounds by UV-detector. Thus NMR spectroscopy is a better universial detection method. A combination of both methods was evident and LC-NMR was born.
Solvents that meet the high requirements of HPLC and proton NMR are needed. But the high throughput of solvents in HPLC does not allow the usage of expensive deuterated solvents as usually required for NMR. HPLC Acetonitrile is often contaminated with impurities containing protons such as propionitrile which is no problem in UV but NMR detection. Therefore a dramatic decrease of proton containing contaminants for LC-NMR solvents is essential.
Acetonitrile LC-NMR is the solvent of choice. It was developed to obtain the superior specifications required for LC-NMR. There are no further signals in 1H-NMR that exceed the size of methyl signals (more than 5% at 3.78 ppm NMR of 0.0006% trimethoxybenzene) at typical LC-NMR conditions