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(usually argon) under reduced atmospheric pressure. Given the characteristics of
plasma, ions and electrons would be difficult to maintain as a whole, which is actually achieved with an electromagnetic field. The main components of such an instrument are plasma-generating system, spectrometer, and computer system. The
plasma- generating system consists of a plasma chamber, a radiofrequency vent generator, and an input system of the analyte (disperser and spray chamber). The plasma
chamber consists of three concentric quartz tubes. Around the top of this tube is an
induced coil connected to a radiofrequency generator. The ionization of argon is
initiated by a spark from a narrow coil. The resulting ions and the electrons attached
to them interact with the fluctuating magnetic field obtained from the inductive coil.
This interaction causes the ions and electrons to be directed in a closed circular path.
The temperature of the plasma thus created is high enough to require thermal insulation of the outer quartz tube, which is made possible by the introduction of argon
tangentially around the tube walls.
Mass spectrometry with inductively coupled plasma (MS-ICP) is the leader technique in the multielement determinations in various samples. The basic components
of an inductively coupled plasma mass spectrometer are (Ammann 2007):
• Sample introduction system
• Generation of ions using inductively coupled plasma
• Plasma/introductory part in vacuum
• Ion-focusing system
• Ion separation and measurement system
Sample introduction system The sample is introduced into the inductively coupled plasma (ICP) in the form of an aerosol, which is formed as a result of passing
the liquid sample through a simple pneumatic nebulizer. Larger aerosol particles
are removed from the spray chamber through a special waste drain. Only smaller
aerosol particles are carried by the flow of plasma argon (Fig. 11.3). The temperature in the spray chamber is precisely controlled by a thermoelectric device to
prevent signal changes that could be caused by large changes in temperature as
well as to reduce the passage of large amounts of fluid into the plasma (Linge and
Jarvis 2009).
Production of ions in inductively coupled plasma (ICP) The generated aerosol
passes into the plasma, which is made possible by a special supply of argon (argon
carrier beam) through a glass attached part marked as a torch. The torch is located
in the center of a copper coil through which an electric current with high power and
frequency passes. The generated magnetic field causes collisions between free electrons and argon atoms, resulting in the formation of ions and more electrons. The
generated energy of the radiofrequency (RF) generator is up to 1600 W. Two operating frequencies are recommended according to Linge (2009) for maximum power
of inductively coupled plasma, namely, 40.68 MHz and 27.12 MHz, which result in
higher plasma temperatures. The high plasma temperature (up to 10,000 K maximum and about 7500 K in the central part) allows rapid drying of the aerosol droplets, atomization, and ionization by removing one electron from each atom. The
V. I. Petropulos and B. Balabanova
(usually argon) under reduced atmospheric pressure. Given the characteristics of
plasma, ions and electrons would be difficult to maintain as a whole, which is actually achieved with an electromagnetic field. The main components of such an instrument are plasma-generating system, spectrometer, and computer system. The
plasma- generating system consists of a plasma chamber, a radiofrequency vent generator, and an input system of the analyte (disperser and spray chamber). The plasma
chamber consists of three concentric quartz tubes. Around the top of this tube is an
induced coil connected to a radiofrequency generator. The ionization of argon is
initiated by a spark from a narrow coil. The resulting ions and the electrons attached
to them interact with the fluctuating magnetic field obtained from the inductive coil.
This interaction causes the ions and electrons to be directed in a closed circular path.
The temperature of the plasma thus created is high enough to require thermal insulation of the outer quartz tube, which is made possible by the introduction of argon
tangentially around the tube walls.
Mass spectrometry with inductively coupled plasma (MS-ICP) is the leader technique in the multielement determinations in various samples. The basic components
of an inductively coupled plasma mass spectrometer are (Ammann 2007):
• Sample introduction system
• Generation of ions using inductively coupled plasma
• Plasma/introductory part in vacuum
• Ion-focusing system
• Ion separation and measurement system
Sample introduction system The sample is introduced into the inductively coupled plasma (ICP) in the form of an aerosol, which is formed as a result of passing
the liquid sample through a simple pneumatic nebulizer. Larger aerosol particles
are removed from the spray chamber through a special waste drain. Only smaller
aerosol particles are carried by the flow of plasma argon (Fig. 11.3). The temperature in the spray chamber is precisely controlled by a thermoelectric device to
prevent signal changes that could be caused by large changes in temperature as
well as to reduce the passage of large amounts of fluid into the plasma (Linge and
Jarvis 2009).
Production of ions in inductively coupled plasma (ICP) The generated aerosol
passes into the plasma, which is made possible by a special supply of argon (argon
carrier beam) through a glass attached part marked as a torch. The torch is located
in the center of a copper coil through which an electric current with high power and
frequency passes. The generated magnetic field causes collisions between free electrons and argon atoms, resulting in the formation of ions and more electrons. The
generated energy of the radiofrequency (RF) generator is up to 1600 W. Two operating frequencies are recommended according to Linge (2009) for maximum power
of inductively coupled plasma, namely, 40.68 MHz and 27.12 MHz, which result in
higher plasma temperatures. The high plasma temperature (up to 10,000 K maximum and about 7500 K in the central part) allows rapid drying of the aerosol droplets, atomization, and ionization by removing one electron from each atom. The
V. I. Petropulos and B. Balabanova