摘要 |
<p>A method of analysing ions by ion mobility separation is disclosed. The method comprises controlling the amount of charge within an ion trap 3 and then pulsing the ions from the ion trap 3 into an ion mobility separator 5. This enables the charge injected into the ion mobility separator 5 to be controlled and hence prevents space-charge interactions between the ions from distorting the ion mobility peaks detected by the detector 7. The charge rate from the ion source, or from a previously released ion packet can be measure by detector 8 or 7 the then this used to control the subsequent packets released from the ion trap 3. The charge released from the ion trap can be controlled by varying the accumulation time of the trap, varying the fill rate, attenuating the beam entering the ion trap or varying the proportion of ions released from the trap.</p> |