Enhancing the sensitivity of LC-NMR

Transfer directly into flow probe with deuterated solvent 

multiple trapping of a single component on the same cartridge followed by elution with a small cell matched volume ( 30 pi) of deuterated solvent to optimise the concentration in the active volume of the NMR flow cell  

drying cartridges and eluting with small volumes of deuterated solvents (cost-effective) gives very little requirement for solvent suppression, leading to significantly cleaner baselines and no loss of useful resonances in the NMR spectrum  

NMR sensitivity is independent of the chromatographic peak volume, allowing more efficient characterisation of late-eluting broad peaks, which were problematic by LC-NMR  

good quality two-dimensional spectra (H-H and H-C) can be acquired in reasonable times for impurities at 0.3% or higher levels. For impurities at 0.2% or less cryogenic flow probe with an active volume of 30 pi is required  

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