Sample is dissolved in a polarvolatile solvent and is put through a hypodermic needle attached to a positive terminal with a high voltage
As particles leave the needle they are ionised and gain a proton
Acceleration
Particles are accelerated through a electric field consisting of 2 negatively charged plates, and therefore increase the kinetic energy of the ions
Ions will accelerate at different speeds depending on their mass to charge ratio lower mz = greater acceleration higher mz = lower acceleration
Ion drift
ions enter a region with no electricfield, so they drift at different speeds depending on their mass to charge ratio
Detection
Ions with a lower mz ratio reach the detector in less time than those with a higher mz, as they reach the detector electrons from the negative plate flow to the positive ions and a current is induced
Time taken to move down the spectrometer is used to determine the mass of isotope
Size of current induced is used to measure the abundance of isotope