CHROMacademy’s Featured Module Orbitrap Mass Analyzers

February 11, 2011

The orbitrap, a new type of mass analyzer, has drawn attention due to its analytical performance.

Introduction to Orbitrap mass analyzers. Ion trapping techniques are important tools in mass spectrometry. However, traditional ion trap mass analyzers havedisadvantages in either performance (insufficient mass accuracy, limited linear range, reduced charge capacity, etc.) or high complexity and cost.

The orbitrap, a new type of mass analyzer, has drawn attention due to its analytical performance in terms of resolution,mass accuracy, space charge capacity and linear dynamic range, relatively small size and cost.

Below is a sample of the content typical of this module. See more Orbitrap mass analyzer pages here >>

Ion Injection

In order to achieve high resolution with the orbitrap, then ions of each mass to charge ratio must have a coherent movement and this isachieved by injecting them in a very short time (or in bursts). The curved linear ion trap is one of the most efficient ways of injectingions to the orbitrap.

Unlike linear ion traps, the curved linear ion trap allows ions to be injected into the orbitrap at a position offset fromits equator and in fact, by doing this, ions will perform coherent axial oscillations almost immediately after injection without the need forany additional excitation; this type of ion injection is known as "fast injection".

When ions are injected at an equatorial position, then ion oscillation is achieved by imposing an additional excitation;this type of ion injection is known as "slow injection".

In order to eliminate gas carryover from the trap (linear or curved), the ion beam is usually deflected by a set of transfer lenses. See more Orbitrap mass analyzer pages here >>