There are a number of ways of achieving sample ionization depending on the sample type, target analyte and desired workflow. These include gas phase methods (electron ionization (EI), chemical ionization (CI), direct analysis in real time (DART) and inductively coupled plasma (ICP)), desorption methods (matrix assisted laser desorption ionization (MALDI), fast atom bombardment (FAB), thermal ionization sources, plasma ionization sources and liquid metal ion sources (LMIS)) and spray methods (electrospray ionization (ESI) and desorption electrospray ionization (DESI)).