This presentation covers basic and instrumentation of ICPMS.. Any suggestions are welcome

1. ICPMS -Basics and instrumentation
Dr. Amol Shinde
Mob: 8452912856
Email:amolshinde005@gmail.com

2. Died because of
Arsenic Poisoning
China's first emperor of unified China,
Qin Shi Huang Di, was driven insane and
killed by mercury pills intended to give
him eternal life
Metal Toxicity: A myth or reality?

4. Measurement techniques
1. AAS (Flame and Graphite Furnace)
2. ICPOES
3. ICPMS
 All of the above techniques require generation of gaseous
atoms of elements
 Signal of Absorption and emission techniques relies on efficient
atomization, which in turn depends on temperature
AAS = 3000K
ICP = 10000 K

5. Measurement Range of techniques
Flame AA
Graphite AA
ICPMS
ICPAES

6. Overview of Atomic Spectroscopy
Techniques
Technique Flame AAS GF AAS ICPAES ICPMS
Detection limits < 10-100 ppb < 100 ppt < 1-10 ppb < 1-10 ppt
Linearity orders 3-4 2-3 5-6 8-9
Elemental coverage Moderate Poor Good Excellent
Simultaneous No No Yes Yes
Speed/ productivity Moderate Slow Fast Fast
Sample volume required ml µl ml ml
Capital cost Low Medium High High
Operating cost Low High Medium High

7. Inductively Coupled Plasma
What is Plasma?
 Gas ionized by high temperature
 Roughly equal number of cations and
electrons present
Both ICPAES & ICPMS employs
Argon Plasma
Plasma temperature:
7,000-10,000ºC
R
T

8.  Both techniques use argon plasma
 What’s the major difference??
The Detection.…..
1. ICPAES measures photons/ light
2. ICPMS measures ions

9. Process in plasma
Ions formed in plasma are expo
to mass compartment through
cone interface

10. Inductively Coupled Plasma Mass spectrometry
 Trace level elemental analysis technique
 First commercially available: 1983
 Multi-element capabilities
 Very low detection limits
 Linear dynamic range of 9 orders
 Applications in variety of segments

11. Schematics of an Typical ICPMS
Computer
interface
Ionization
source –
plasma
Cones/
ion extraction
Lenses/
ion focusing
Detector/
EMT
Mass Filter/
quadrupole
RF
generator
Sample
introduction
system
Argon
Sample

12. 1. Sample transported to nebulizer by peristaltic pump
2. Liquid sample split into droplets by high speed argon gas flow
3. High pressure at tip of nebulizer allows small portion of droplets
to become aerosol
4. Argon begins to serve as aerosol transporter & aerosol blown into
the spray chamber
5. Fine aerosol goes to plasma via injector whereas larger droplets go
to the drain
Sample introduction system

13. Sample introduction system
Sample
aerosol
Spray
chamber
Fine droplets go to plasma
(torch)
larger droplets go to drain
Liquid
sample
Nebulizer
Argon
gas
Peristaltic
pump

14. Plasma (ICP) torch
Consists of 3-concentric tubes fused
together
Generally made up of quartz or ceramic
Role of sustaining high temperature plasma

15. RF Generator
 Can be of 27 MHz or 40 MHz frequency
 Used to apply RF power over the torch using a coil
 RF Coil can be water or air cooled
 Cooling water circulator required to cool the RF
generator unit
Typical RF coil

16. 0.8 to 1.2 mm
0.4 to 0.8 mm
Interface between plasma and mass analyzer
It cope up the pressure difference between Plasma and mass analyzer

17. quadrupole mass analyzer
 Mass range 6 to 260 amu (Li to U)
 Separates ions in rapid sequential m/z scan
 Typically made up of molybdenum
 Other types of mass analyzers are also available like
TOF (time of flight) or
High resolution magnetic sector (single or multi-collector)
Two pairs of rods:
Attach + and - sides of a variable dc source
Apply variable radio-frequency ac potentials to each pair
of rods.
Ions are accelerated into the space between the rods by
a small potential (5-10V)
Ions having a limited range of m/z value reach the
transducer.

18. Detectors in ICPMS
 Channel electron multiplier
Similar to PMT
Open glass cone coated
with semiconductor type
material that generates
electrons from ions
impinging on its surface
Most common

19. Less popular
Now a days used in conjunction with sector field ICPMS for
isotopic ratio measurements

20. Interferences in ICPMS

21.  Arise due to viscosity and surface tension difference between
standard and samples being analyzed
 This affects sample uptake rate, droplet size formed at
nebulizer tip
 Causes change in nebulization efficiency
1% HNO3
5% H2SO4
MIBK



Solvent Type Uptake Rate Droplet Size
Most common = Nitric acid, as most of the metal nitrates are water
soluble
Physical Interferences

22. 0.6
0.8
1
1.2
0 0.2 2 20
Relativeintensity
Nitric acid
concentration(％)
0.6
0.8
1
1.2
0 0.2 2 20
Hydrochloric acid
concentration (%)
0.6
0.8
1
1.2
0 0.2 2 20
Sulfuric acid
concentration(％)
Fe
Zn
Physical Interferences:
Example
 As acid concentration increases, signal intensity decreases
 This is also dependent upon type of acid used
What’s the
solution then

23. Standard １ Standard 2 Standard 3 ････ Actual sample
How to reduce physical interferences
Most common elements Y, Bi, Sc and
Rh
Monoisotopic
Very rare in different matrices
Add internal standard

24. Spectral Interferences
1. Polyatomic (molecular) ions
 Generated due to combination of sample ions with Ar or other
matrix components S, Cl, O, H, N
 e.g.: 40Ar16O+ (interference for 56Fe＋)
 e.g.: 47Ti16O+ (interference for 63Cu+)
2. Isobaric ions
 e.g.: 112Cd+,112Sn+ (interference for each other)
3. Doubly charged ions
 e.g.: 110Sn2+ (interference for 55Mn+)

25. Measurement element ions
Polyatomic ion
Isobaric ions
Doubly Charged ions
m/z
How it affects analysis?
 So there is a need to remove such interferences

26. 1. Choose another isotope of analyte element
 May be less abundant (low sensitivity)
 Not all elements have another isotope available
2. Matrix alteration through elimination
 For e.g. avoid use of S, Cl containing reagents
3. Use of Collision cell or reaction cell to destroy interferences
Ways to overcome spectral interferences

27. Computer
interface
Ionization
source –
plasma
Cones/
ion extraction
Lenses/
ion focusing
EMT/ ion
detection
Mass Filter/
quadrupole
RF
generator
Sample
introduction
system
Argon
Sample
Collision cell technology:
where it is employed?

28. Computer
interface
Ionization
source –
plasma
Cones/
ion extraction
Lenses/
ion focusing
EMT/ ion
detection
Collision cell
(for
interference
removal)
Mass Filter/
quadrupole
RF
generator
Sample
introduction
system
Argon
Sample
Collision cell technology:
where it is employed?

29. Collision cell technology:
Principle of collision cell functioning
 Collision cell is usually a multipole (quadrupole, hexapole or
octapole) system
 A collision gas such as He/H2 is introduced into cell, which then
collide with ions coming from plasma source
 This results in kinetic energy loss primarily for polyatomic ions
which are bigger in size
 Thus polyatomic ions lose energy and doesn’t enter mass
quadrupole because of energy barrier at the end of collision
cell

30. KED(energy discrimination)
Plasma ion beam
Collision cell with helium
Quadrupole mass filter
Monoatomic ion Fe+ Polyatomic ion ArO+ Collision gas He
Collision cell technology:
How it works?
Analyte ion Interference
Break the polyatomic species into
atoms

31. Collision cell technology:
Possible gases that could be used
 He, H2 CH4, O2 NH3 CH3F
 Collison cell could be provided with one or multiple gas lines to
incorporate different gases
 Some of the gases listed are highly reactive like NH3, H2 and generally
mixtures with argon are recommended for use
 Also unpredictable reaction byproducts may also formed with sample
matrix resulting in cell contamination

33. Advances in ICPMS
 Single particle ICPMS- Nanoparticle analysis. (First use
reported in 2006)
Nanoparticles are advanced materials, but their risk assessment
should be done for e.g. Au, Ag, TiO2, SiO2
 Speciation analysis (HPLC-ICPMS)
In addition to total element concentration , chemical form should
be quantified for e.g Mercury and methyl mercury,
Regulation are going to be implemented

34.  Triple QQQ ICPMS ( Introduced in 2013)
It is specially used for Proteomics
For S measurement
For Se measurement

35. Thank you very much for
your patient listening……