inductively coupled plasma spectroscopy

1. Principles of Inductively coupled plasma spectrometry
Submitted by: Shweta Pandey
ID: 59196
M.Sc. Environmental science
C.B.S.H
Submitted to: Dr A.K Tyagi
Assistant Professor
Department of Soil
Science
APS 624 Analytical Techniques and instrumental methods in soil and plant
analysis

2. Introduction
ICP (Inductively Coupled Plasma)
Spectroscopy is an analytical method used to
detect and measure elements to analyze
chemical samples. The process is based on the
ionization of a sample by an extremely hot
plasma, usually made from argon gas.

3. ICP helps in
• Identifying and quantifying components for chemical sample
analysis.
• Figuring out the concentration of a particular element in a sample.
• Trace element measurements in biological fluids.
• Elemental analysis of several sample types.

4. Techniques of ICP
•ICP-AES (Inductively Coupled Plasma Atomic Emission
Spectrometry)
•ICP-MS (Inductively Coupled Plasma Mass
Spectrometry)

5. Inductively coupled plasma atomic
emission spectrometry
• ICP-AES is a spectral method used to determine very precisely the elemental
composition of samples.
• ICP-AES uses high-energy plasma from an inert gas like argon to burn analytes
very rapidly.
• The color that is emitted from the analyte indicates the elements present, and
the intensity of the spectral signal indicates the concentration of the elements
that is present.

6. Principles of ICP AES
Excitation of atomized metal with inductively coupled plasma, followed by emission
of light of its own characteristics wavelength and correlation of emitted light with
the concentration of metal ICP- AES.
Excited due
to plasma
heat
Solution
Ground
state
Gas
Excited
atom
Gas
Solid
residue
Mist
Nebulizer
Solvent
Evaporat
es
Solid
vaporized
Atomizes
Return to ground state by
emitting light of its own
characteristics

7. Instrumentation
An ICP-AES instrument consist of a sample delivery system, an IC plasma to
generate the signal, one or more optical spectrometers to measure the
signal, and a computer for controlling the analysis.
Sample delivery system:
The peristaltic pump draws up sample solution and delivers it to the nebulizer
which converts the solution to an aerosol that is sent to the spray chamber
where the larger droplets fall to the bottom of the chamber and exit through
the drain.

8. ICP torch
The ICP torch is made up of quartz or ceramic. Inside it, three tubes injector, middle
and outer tube are present.
Argon gas supplied to middle tube create plasma flame and argon gas present in
outer tube act as coolant. Around plasma there is induction coil and RF coil which
induces a high-frequency alternating current, creating an intense electromagnetic
field that ionizes the argon gas, forming the high-temperature plasma.

9. Spectrometer
• Once the atoms in a sample have been excited by the plasma, they will emit radiation at
specific wavelengths.
• No two elements will emit radiation at the same wavelengths.
• The function of the spectrometer is to diffract the emitted radiation from the plasma into
wavelengths.
• Then each wavelength will be directed to a detector.
• These detectors are connected to a computer for data analysis .

11. • Nebulizer converts liquid solution to fine particle of aerosol/mist.
• Solvent gets vaporized leaving behind the solid residue.
• The solid residue gets vaporized to gaseous from due to high temperature of the plasma
and molecules dissociate to atoms.
• The metal atoms get excited to higher energy level .
• The excited metal atoms emit light of its own characteristics wavelength by returning
back to ground state.
• ICP source consists of a flowing stream of argon gas ionized by an applied radio
frequency field.
• This field is inductively coupled to the ionized gas by water cooled coil surrounding a
quartz torch that supports and confines the plasma

12. • The sample is first introduced into the plasma, which is created by ionizing an
inert gas such as argon using a high frequency electromagnetic field.
• The sample aerosol is directed into the ICP, subjecting the constituent atoms to
temperature of about 5000 to 10000 K.
• This high temperature results in almost complete dissociation of molecules.
• These excited atoms then emit light at specific wavelengths, which are detected
by a spectrometer and used to identify the elements present in the sample.
• The radiation emitted by the excited atoms is recorded by one or more optical
spectrometers calibrated readings against standards the technique provides a
quantitative analysis of the original sample.

13. Wavelengths of different elements
Cu 325nm
Ni 393nm
Ba 554nm
Na 589nm
Ca 622nm
Li 670nm

14. Advantages
• ICP-AES is capable of detecting trace amounts of elements , typically in the parts-per-
billion to parts-per-million range
• ICP-AES provides accurate and precise results, making it a reliable technique for
elemental analysis.
• ICP-AES is capable of analysis multiple element simultaneously, making it a highly
efficient technique for elemental analysis
• ICP-AES provides rapid analysis , making it time-efficient technique .

15. Applications of IPC-AES
• Analysis of agricultural products, food and soil sample.
• Presence of lanthanides and other elements in rock samples.
• In waste water analysis and metals in soil.
• Traces of metal like Cu, Fe, Mo and Zn in beverages.

16. ICP-AES ICP

17. Inductively coupled plasma mass
spectrometry
Inductively coupled plasma mass spectrometry (ICP-MS) is a type of mass
spectrometry that uses an inductively coupled plasma to ionize the sample.
It atomizes the sample and creates atomic and small polyatomic ions, which
are then detected. It is known and used for its ability to detect metals and
several non-metals in liquid samples at very low concentrations. It can
detect different isotopes of the same element, which makes it a versatile tool
in isotopic labeling.
Compared to atomic absorption spectroscopy, ICP-MS has greater speed,
precision, and sensitivity.

18. Principle
This technology couples use of an ICP with MS for elemental
analysis by generation of ions. The ICP is involved in generation of
high temperature plasma source at 10,000 degree Celsius, sample
is passed. The elements in the sample at such high temperature
are ionized and directed further into the MS.
The ions enter into an electric field and are separated according to
their mass/charge ratio by MS. The MS then sorts the ions
according to their mass/charge ratio followed by directing them to
an electron multiplier tube detector. The detector then identifies
and quantifies each ion.

19. Mass Spectrometer
The mass spectrometer is an instrument in which substance in gaseous or
vapour state is bombarded with beam of electrons to form a positively
charged ions which are further sorted to mass to charge ratio to record their
masses and relative bond.
All mass spectrometers consist of three basic parts:
• Ion source
• Mass analyser
• Detector system

21. Component
• High-frequency generator: The task of the generator is to (inductively)
create an alternating magnetic field within the plasma coil in order to couple
with the energy in a flow of gas.
• Plasma torch: The torch is a multi-walled quartz tube whose outer channel
contains the noble gas argon. The open end of the plasma torch is
surrounded by the plasma coil or induction coil, which is responsible for
transferring the energy to the argon stream.
• Plasma coil: The plasma coil is part of the high-frequency generator. It
conducts an oscillating current that generates an electromagnetic field. This
field accelerates charged particles, thereby transmitting energy to the argon
plasma. The noble gas argon is ionized in the process and heated to a
temperature between roughly 6,800 and 10,000 K.

23. RF generator
Sample introduction system
Plasma source
Mass spectrometer
interface
Lens system
Mass filter Detector Computer Printer

24. Process
• Sample Introduction: The analysis begins with the introduction of
the sample into the ICP, typically a fine aerosol produced by a
nebulizer.The sample can be a liquid, solid or gas.
• Formation of ICP: An RF (radiofrequency) coil induces a high-
frequency alternating current in a stream of inert gas(argon).This
creates an extremely hot and ionized gas called the inductively
coupled plasma.
• Ionization and Atomization: The high temperature of the plasma
causes the sample to undergo complete atomization and ionization.
The sample is converted into a mixture of ions and neutral atoms.

25. • Extraction of Ions: Ions from the plasma are extracted and
accelerated into the mass spectrometer using a set of lenses.
This process is often facilitated by a sampler and skimmer
cone.
• Ion Optics: The accelerated ions pass through a series of ion
optics, which include a quadrupole or other mass analyzer. The
mass analyzer separates ions based on their mass-to-charge
ratio (m/z). Only ions with the desired mass are allowed to pass
through.
• Detection: The separated ions are detected by a detector
system, commonly a Faraday cup or an electron multiplier. The
detector generates an electrical signal proportional to the
number of ions striking it.

26. • Quantification: The generated signal is then processed to
determine the concentration of each element in the sample.
Calibration is performed using standards with known
concentrations to establish a relationship between the signal
intensity and the concentration of the elements.
• Isotopic Information: ICP-MS can provide information about
isotopes of elements. For each element, different isotopes may
exist with varying numbers of neutrons. The mass spectrometer
can distinguish between these isotopes, providing isotopic
composition data.
• Data Analysis: The collected data are analyzed using
specialized software, and the results are typically expressed as
concentrations of elements in the original sample.

27. Working of ICP-MS

28. Advantages of ICP-MS
• ICP-MS is highly sensitive and can detect trace levels of elements in the
parts per trillion or even parts per quadrillion range. This sensitivity is
crucial for analyzing samples with low concentrations of elements.
• ICP-MS can analyze a broad range of elements across the periodic table
simultaneously. This makes it versatile for applications in environmental
monitoring, geological studies, pharmaceuticals, and metallurgy, among
others.
• ICP-MS provides accurate and precise quantitative analysis of elements
in a sample.

29. • Compared to some other analytical techniques, ICP-MS provides
relatively fast analysis times. This is important where rapid results
are needed.
• ICP-MS is less prone to spectral interferences compared to some
other techniques like atomic absorption spectroscopy. This is due
to the high-temperature plasma source, which reduces the
likelihood of molecular interferences.
• ICP-MS is capable of measuring isotopic ratios for elements that
have multiple stable isotopes.

30. Applications
• Monitoring trace metal concentrations in water, soil, and air for
environmental assessment.
• Testing pharmaceutical products for elemental impurities to ensure
compliance with regulatory standards.
• Quantifying trace elements in biological fluids (blood, urine, serum) for
medical diagnostics. Investigating metal toxicity and deficiencies in
human and animal tissues.
• Analyzing trace elements in forensic samples for criminal
investigations. Identifying gunshot residues and other trace evidence.

31. ICP-MS

32. ICP- AES ICP-MS
High Low
In ppm In ppt
Metals and Non-metals Trace elements
Moderate resolution Excellent resolution
Less expensive More expensive
Resolution
Detection amount
measurement
Elemental
range
Detection
Limit
Cost

33. References
• Inductively coupled plasma atomic emission spectroscopy. (2023). In Wikipedia.
https://en.wikipedia.org/w/index.php?title=Inductively_coupled_plasma_atomic_
emission_spectroscopy&oldid=1189484901
• Inductively coupled plasma -atomic emission spectroscopy. (2016, September 1).
https://www.slideshare.net/ParimiAnuradha/inductively-coupled-plasma-atomic-
emission-spectroscopy-65578961
• Inductively coupled plasma mass spectrometry. (2023). In Wikipedia.
https://en.wikipedia.org/w/index.php?title=Inductively_coupled_plasma_mas
s_spectrometry&oldid=1189493864

34. Thankyou