ABSTRACT
This chapter takes a look at the region of the inductively coupled plasma-mass spectrometric (ICP-MS) where the ions are generated—the plasma discharge. It gives a brief historical perspective of some of the common analytical plasmas used over the years and discusses the components used to create the ICP. The chapter also explains the fundamental principles of formation of a plasma discharge and how it is used to convert the sample aerosol into a stream of positively charged ions of low kinetic energy required by the ion-focusing system and the mass spectrometer. In the early days, when researchers were attempting to find the ideal plasma source to use for spectrometric studies, it was not clear which approach would prove to be the most successful. The plasma torch consists of three concentric tubes, which are normally made from quartz. The chapter discusses the mechanism of formation of the plasma discharge in greater detail.
