Abstract: A mass spectrometer is disclosed wherein ions are passed through an ion mobility separator and are then mass analysed by a Time of Flight mass analyser. Multiple sets of mass spectral data are obtained which are then post-processed so that mass spectral data relating to ions having undesired charge state(s) is filtered out. The resultant mass spectrum comprises ions having a desired charge state.

Abstract: A method of mass spectrometry is disclosed wherein a gas collision cell is repeatedly switched between a fragmentation and a non-fragmentation mode. Parent ions from a first sample are passed through the collision cell and parent ion mass spectra and fragmentation ion mass spectra are obtained. Parent ions from a second sample are then passed through the collision cell and a second set of parent ion mass spectra and fragmentation ion mass spectra are obtained. The mass spectra are then compared and if either certain parent ions or certain fragmentation ions in the two samples are expressed differently then further analysis is performed to seek to identify the ions which are expressed differently in the two different samples.

Abstract: A method of mass spectrometry is disclosed wherein a gas collision cell is repeatedly switched between a fragmentation and a non-fragmentation mode. Parent ions from a first sample are passed through the collision cell and parent ion mass spectra and fragmentation ion mass spectra are obtained. Parent ions from a second sample are then passed through the collision cell and a second set of parent ion mass spectra and fragmentation ion mass spectra are obtained. The mass spectra are then compared and if either certain parent ions or certain fragmentation ions in the two samples are expressed differently then further analysis is performed to seek to identify the ions which are expressed differently in the two different samples.

Abstract: A MALDI sample plate 1 is disclosed which comprises a metallic substrate 2 having a circular groove or moat 3. A hydrophobic polytetrafluoroethylene layer 4 is applied to the substrate 2 and a central portion 5 of the substrate 2 is laser etched which roughens the surface of the substrate 2. A thin polystyrene layer is then applied to the polytetrafluoroethylene layer 4 and the central portion 5.

Abstract: A mass spectrometer is disclosed comprising an ion mobility spectrometer in combination with a quadrupole mass filter which is scanned in synchronization with the pulsing of ions into the ion mobility spectrometer thereby enabling ions having a particular charge state to be preferentially transmitted. Another embodiment replaces the quadrupole mass filter with an axial time of flight mass filter and an injection electrode.