Inlet Devices:

The purpose of the inlet device is to load the sample into the ionisation chamber. The device used depends on the nature of the sample. The solid samples are placed on the tip of a rod called direct insertion probe which is inserted into the evacuated chamber having a vacuum-tight seal. This is after that heated to evaporate or sublime the sample to get the molecules in the gas phase. The gases and heat volatile liquids, on the other hand are generally introduced through specially designed devices with controlled flow. A liquid samples are also suitably evaporated. Once the sample is evaporated the gaseous molecules are then ionised through a suitable technique; this usually is accompanied by fragmentation also. While the analyte is thermally labile i.e., it can decompose upon heating, then we need to use other methods such as desorption or desolvation methods (discussed in the next sub section) to bring the analyte into the vapour phase.