Question

What is the function of the collision cell in tandem mass spectrometry?

Answer 1

Mass spectrometer is a device that seperates ionic species based upon their mass to charge ratio. Collision cell is a chamber in which accelerated molecular ions are allowed to collide with neutral gas molecules such as argon or nitrogen. This results in brekage of bonds in the molecule due to increased internal energy of the molecule and the molecule fragments into smaller ions. This is known as Collision Induced Dissociation(CID).

The resulting fragment ions are then analysed by another Mass spectrometer in tandem. The fragment ions are used to decipher the structure of the parent molecular ion. The fragment ions produced by a peptide is used to determine the amino acid sequence of the peptide.