Mass spectrometry

 
Our main bioanalytical apparatus is a Q-TOF MS-MS spectrometer. This hybrid Quadrupole-Time-of-flight technology ( LC-Q-TOF MS-MS) offers many advantages for the identification of biotransformation pathways of drugs and biomolecules.

This quite old technology has made a recent come-back, thanks to modern advances in electronics and computer control. With its remarkable spectral resolution couples to high speed data acquisition, it ideally suits for mass-spectrometric structural identification in the context of ultra-fast separation methods (HTS : high sample throughput screening)

Recording of full mass spectra at medium resolution (<5ppm error on the exact mass of ions) over many short observation times (<100ms) allows to analyse complexe mixtures (raw samples) without any loss of chromatographic separation power ( by deconvolution of exact ions masses).

For this reason, Q-TOF MS-MS even allows parallel determinations on series of samples injected on several different columns: the chromatographic effluents are then brought sequentially into ionisation chamber of the instrument by a rotating valve. The Q-TOF technology is also suitable for multiple parallel kinetic studies (the N in 1 approach).

 
Key features

  • Spectral resolution : easier structural identification, elimination of isobaric problems
  • High sensitivity in full scan mode : greater number of spectral information
  • Specific advantages for metabolism studies
    • improved selectivity due to high resolution and S/N ratio -> safety margin
    • improved identification of metabolites in plasma
    • wide mass range for biomolecules (> 20.000 daltons)
  • High speed data acquisition - sample throughput
    • insensitive to effects of concentration variations - impulsions
    • deconvolution of unresolved chromatographic peaks
    • spectra accumulation and averaging for high accuracy and sensitivity
    • applicable to turbulent flow LC (ultra high speed LC)
    • applicable to capillary electrophoresis and micro-LC
    • apllicable to the 'N in 1' approach in exploratory pharmacokinetics
    • capable of quasi-simultaneously analysing effluents of several LC columns