<P> A linear quadrupole ion trap is similar to a quadrupole ion trap, but it traps ions in a two dimensional quadrupole field, instead of a three - dimensional quadrupole field as in a 3D quadrupole ion trap . Thermo Fisher's LTQ ("linear trap quadrupole") is an example of the linear ion trap . </P> <P> A toroidal ion trap can be visualized as a linear quadrupole curved around and connected at the ends or as a cross section of a 3D ion trap rotated on edge to form the toroid, donut shaped trap . The trap can store large volumes of ions by distributing them throughout the ring - like trap structure . This toroidal shaped trap is a configuration that allows the increased miniaturization of an ion trap mass analyzer . Additionally all ions are stored in the same trapping field and ejected together simplifying detection that can be complicated with array configurations due to variations in detector alignment and machining of the arrays . </P> <P> As with the toroidal trap, linear traps and 3D quadrupole ion traps are the most commonly miniaturized mass analyzers due to their high sensitivity, tolerance for mTorr pressure, and capabilities for single analyzer tandem mass spectrometry (e.g. product ion scans). </P> <P> Orbitrap instruments are similar to Fourier transform ion cyclotron resonance mass spectrometers (see text below). Ions are electrostatically trapped in an orbit around a central, spindle shaped electrode . The electrode confines the ions so that they both orbit around the central electrode and oscillate back and forth along the central electrode's long axis . This oscillation generates an image current in the detector plates which is recorded by the instrument . The frequencies of these image currents depend on the mass - to - charge ratios of the ions . Mass spectra are obtained by Fourier transformation of the recorded image currents . </P>

Which type of spectrometry results in the destruction of the sample