Patent ID: 10504708

Abstract:
The invention relates to mass spectrometric analyses of heavy molecules and molecular complexes having molecular weights sometimes well above 100,000 daltons, by collision treatment in linear RF multipole collision cells. A mixture of at least one light collision gas (<40 daltons) and at least one heavy collision gas (>80 daltons) is provided in a linear RF collision cell. The heavy collision gas results in high-momentum and high-energy collisions, which leads to splitting and further fragmentation of portions of the heavy molecular (complex) ions. For this purpose, the molecular (complex) ions are axially injected into the collision cell at kinetic energies of several hundred electronvolts per charge; due to the collisions with the heavy collision gas molecules they are deflected from the axis and excited to undergo strong oscillations in the radial direction in the focusing RF field. The light collision gas serves in turn for damping these oscillations.