Chromatography, Magnetic Resonance & Mass Spectrometry

Provides the exact mass of the analyzed sample and therefore access to the sum formula

The LC-NMR/MS setup was first introduced by Bruker BioSpin in 1999. An LC-NMR system including a Bruker Peak Sampling Unit (BPSU-36) was coupled with a Bruker Daltonics esquire series ion trap mass spectrometer via a Bruker NMR-MS interface (BNMI). Nowadays mostly maXis / micrOTOF time-of-flight mass spectrometers are used in hyphenated systems.

The time-of-flight mass spectrometers provides the exact mass of the analyzed sample and therefore access to the sum formula. This, together with the NMR spectrum for the compound, often already provides the answer to your questions.

The mass spectrometers and the controlling software are completely integrated into the LC-SPE-NMR setup. During chromatographic separation the mass spectrometer provides the mass spectra of the eluted peaks. Likewise they allow HyStar™ to trigger collection of chromatographic peaks on SPE cartridges (LC-SPE™ NMR) based on mass chromatograms.

LC-SPE NMR and mass spectroscopy go especially well together. The SPE as interface between LC and NMR allows the usage of completely non-deuterated solvents during the chromatographic separation, and thus simplifies the acquired MS spectra. Sample enrichment through repeated chromatographic runs requires highly reliable peak detection. This peak detection is accomplished much easier through the use of highly sensitive mass chromatograms, then with UV chromatograms.

The integration of the MS into a LC-SPE-NMR setup is accomplished with a BRUKER NMR MS Bridge. The main task of this interface is the transfer of a fraction of the flow into the ion source to allow parallel LC-MS analysis where the main part of the sample remains available for NMR analysis.

The NMR MS Bridge is indispensable for combined NMR and MS analysis as it aligns UV and MS data for proper on-line peak detection, improves peak shape of the low flow chromatogram in the MS, allows software controlled definition of the flow path and allows infusion of calibrant solution for each analysis.



NMR MS Bridge
The Bruker NMR-MS Bridge