The invention provides methods and apparatus for tandem mass spectrometry (MS/MS) in which parent ions generated from a sample are passed through a mass filter (2) and are fragmented into daughter ions in fragmentation means (3), the daughter ions being passed through a discontinuous output mass analyser, such as a time-of-flight analyzer (16) or an ion storage device (29). The range of possible parent mass-to-charge ratios is split into a plurality of smaller ranges, and the mass filter (2) is ...

A method of managing the data for a plurality of ion spectra, including at least one progenitor ion spectrum and a plurality of spectra of ion fragments that are descendants of the progenitor ion, stored in a memory includes displaying indicia of the spectra on a display screen in a graphical user interface such that descendant ions have indicia that are displayed as subordinate to indicia of their progenitor ions, and manipulating the spectra data by selection of the displayed indicia with a gr...

A positive ion of an isomer is generated in an ion source and introduced into a target chamber filled with a target alkali metal so that it is dissociated into a neutral fragment which is then subjected to charge inversion to generate a negative ion. By measuring the mass spectrum of the negative ion, the isomer can be detected at a higher resolution than has been possible by CID and other conventional mass spectroscopic techniques.

The invention consists of deriving the control of the space charge in the ion trap for the initial daughter ion spectrum from the filling rates of previous normal spectra, from the abundance ratio of the parent ions to be isolated to the total ions in the spectrum, and from the at least roughly known isolation and fragmentation yields. For further daughter ion spectra, the resulting measured overall filling rate with daughter ions may be used. The same applies in an analogue way to spectra of is...

There is disclosed a method of extracting information about the mass of a substance from a complex mass spectrum containing peaks arising from polyvalent ions. These polyvalent ions possess electric charges which are integral multiples of the elementary electric charge. Ions including these polyvalent ions are detected, and a mass spectrum is obtained. On the mass spectrum, ion intensity I is represented as a function of a variable x corresponding to mass-to-charge ratio. The mass spectrum, give...

A method of identifying and quantifying the chemical components of a mixture of organic material comprises subjecting the organic material to chromatography to separate the components of the mixture and subjecting the separated materials to spectrometry to detect and identify the components. A variable selection procedure is described that results in well resolved chromatography which facilitates the proper interpretation.

A method for analyzing chemical species and determining the molecular weight of a parent molecule. Multiply charged ions are produced from the parent molecule by adding adduct ions thereto. A mass analysis is conducted of the multiply charged ions to generate mass/charge data. The molecular weight is calculated by using a deconvolution procedure in which the adduct ion mass and the molecular weight of the parent molecule are both treated as unknowns. Alternatively, a modified deconvolution proce...

An analyzing portion searches a mass spectrum for a mass peak exceeding a threshold level and adds the mass corresponding to the searched peak to the mass differences listed in an adduct ion table stored in a table, thereby forming a quasi-mass spectrum. The analyzing portion compares the formed quasi-mass spectrum with a measured mass spectrum in terms of mass. If agreement in mass between both the spectra is found, an index S is incremented by one and finally a total value of the index S is ca...

Methods and apparatus for mass filtering based on a-priori biomarker knowledge and elution time intervals for selected ion species from a separation device. A sample may be screened for biomarker patterns based on distinct elutions times for selected ions or peptides. A mass spectrum for species of interest can be tailored by filtering out undesired ions by measuring corresponding elution times and determining a priori selected elution time intervals for desired ion species only. The invention a...

A method of ion kinetic energy analysis is provided by forming ions including metastable ions from a vaporized sample material, accelerating the ions toward a target collector electrode through an electric field, and for an interval of time for enhancing the probability of decomposition of the metastable ions in an area along a trajectory of the ions intermediate the ion source and the electric field, varying the electric field intensity for causing daughter ions of differing kinetic energy to b...