Mass spectrometry

all about mass spectrometry.

1. LOGO
Mussarat Jabeen

2. •Powerful analytical technique
•Smallest scale
•Destructive technique
•Useful for identification of species
According to the IUPAC
(International Union of Pure and
Applied Chemistry), it is the branch
of science dealing with all aspects of
mass spectroscopes and results
obtained with these instruments.

3. Brief History of Mass Spectrometry
Nobel prize pioneers
Mass spectrometer
Contents
Structural analysis and Fragmentation Patterns
interpretation of mass spectrum
Applications of mass spectrometry

4. 1897
1919
1934
1966
J.J. Thomson. Discovered electrons by cathode
rays experiment. Nobel prize in 1906.
Francis Aston recognized 1
st
mass spectrometer
and measure z/m of ionic compounds.
First double focusing magnetic analyzer was
invented by Johnson and Neil.
Munson and Field described chemical
ionization.
Brief History of Mass Spectrometry

5. 1968
1975
1985
1989
Electrospray Ionization was invented by Dole,
Mack and friends.
Atmospheric Pressure Chemical Ionization
(APCI) was developed by Carroll and others.
F. Hillenkamp, M.Karas and co-workers describe
and coin the term matrix assisted laser
desorption ionization (MALDI).
w. Paul discovered the ion trap technique.

6. Joseph John
Thomson
1906 Nobel Prize for
Physics
(theoretical and
experimental
investigations on the
conduction of
electricity by gases)
Francis William
Aston
1922 Nobel Prize for
Chemistry
(mass spectrograph,
of isotopes, in a
large number of non-
radioactive
elements)
Wolfgang Paul
1989 Nobel Prize for
Physics
(for the development
of the ion trap
technique)
John Bennet
Fenn
2002 Nobel Prize
for Chemistry
(for the
development of
Soft Desorption
ionization Method)
Koichi Tanaka
2002 Nobel Prize
for Chemistry
(mass
spectrometric
analyses of
biological
macromolecules)
Nobel prize pioneers

7. Mass spectrometer

8. Understanding Mass Spectrometry
In a mass spectrometer, the same thing is
happening, except it's atoms and molecules that are
being deflected, and it's electric or magnetic fields
causing the deflection. It's also happening in a cabinet
that can be as small as a microwave or as large as a
chest freezer.

9. Mass spectrometer is similar to a prism.
In the prism, light is separated into its
component wavelengths which are then
detected with an optical receptor, such as
visualization. Similarly, in a mass
spectrometer the generated ions are
separated in the mass analyzer, digitized and
detected by an ion detector.

10. Basic Components of Mass Spectrometer
Four basic components
•Sample inlet
•Ionization source
•Mass analyzer
•Ion detector

11. Mass spectrometer
Sample Introduction Techniques
Initial pressure of sample is 760 mmHg or
~10-6 torr
•Direct Insertion (commonly used in MALDI)
•Direct infusion or injection (commonly used in ESI)
Two techniques

12. Mass spectrometer
Direct Insertion sample introduction technique
very simple technique
Sample is placed on a prob and inserted into ionization source and then
subjected to any number of desorption processes, such as laser
desorption or direct heating, to facilitate vaporization and ionization.

13. Direct infusion or injection sample introduction technique
Frequently used due to high efficiently
Used in coupling techniques like GC-MS and HPLC-MS

14. IonizationMethods used in Mass spectrometry
Commonly used
•Protonation
•Deprotonation
•Cationization
•Transfer of a charged molecule to the gas phase
•Electron ejection
•Electron capture

15. Protonation
Formation of positive ions by the addition of a proton
Used for basic compounds like amines, peptides
Used in MALDI, APCI and ESI

16. Deprotonation
Give net negative charge of 1-by removal of one proton
Used for acidic species like phenols, carboxylic acid, sulfonic acid etc.
Used in MALDI, APCI and ESI

17. Cationization
produces a charged complex by non-covalently adding a
positively charged ion like alkali metal ion or ammonium ion
to a neutral molecule.
Used for Carbohydrates
Used in MALDI, APCI and ESI

18. Transfer of a charged molecule to the gas phase
Cation from solution to gas
Used in MALDI or ESI

19. Electron ejection
Electron is ejected to give positive ion
Usually for non-polar compounds with low
molecular weights like anthracene.

20. Electron capture
a net negative charge of 1-is achieved
with the absorption or capture of an
electron.
Used for halogenated compounds

21. Ionization Sources in mass spectrometer
•Electrospray Ionization (ESI)
•Nanoelectrospray Ionization (NanoESI)
•Atmospheric Pressure Chemical Ionization (APCI)
•Atmospheric pressure photoionization (APPI)
•Matrix-assisted laser desorption/ionization mass
spectrometry (MALDI-MS)
•Fast Atom Bombardment (FAB)
•Electron Ionization (EI)
•Chemical Ionization (CI)
•Thermal ionization (TI)

22. Ionization Sources
Hard ionization sources Soft ionization sources
leave excess
energy in
molecule and
produced stable
fragments which
is not further
fragarmented
Little excess
energy in
molecule and
produced
unstable
fragments
which are
again
fragmented.

23. Electrospray Ionization (ESI)
For example peptides, proteins, carbohydrates,
small oligonucleotides, synthetic polymers, and
lipids
The sample solution is sprayed from a region of the
strong electric field at the tip of a metal nozzle
maintained at a potential of anywhere from 700 V to
5000 V. The nozzle (or needle) to which the potential is
applied serves to disperse the solution into a fine spray
of charged droplets. Either dry gas, heat, or both are
applied to the droplets at atmospheric pressure thus
causing the solvent to evaporate from each droplet

24. Nanoelectrospray Ionization (NanoESI)
where the spray needle has been made very small and
is positioned close to the entrance to the mass analyzer.
The end result of this rather simple adjustment is
increased efficiency, which includes a reduction in the
amount of sample needed.
•Very sensitive
•very low flow rates
•Very small droplet size (~5µ)

25. Atmospheric Pressure Chemical Ionization (APCI)
the liquid effluent of APCI is introduced directly into the ionization source.
However, the similarity stops there. The droplets are not charged and the
APCI source contains a heated vaporizer, which facilitates rapid
desolvation/vaporization of the droplets. Vaporized sample molecules are
carried through an ion-molecule reaction region at atmospheric pressure.

26. Atmospheric pressure photoionization (APPI)
it generates ions directly from
solution with relatively low
background and is capable of
analyzing relatively nonpolar
compounds.
APPI vaporized sample passes through ultra-violet
light.
APPI is much more sensitive than ESI or APCI.

27. Matrix-assisted laser desorption/ionization mass spectrometry
(MALDI-MS)
the analyte is first co-crystallized with a large molar excess of a matrix compound, usually a UV-
absorbing weak organic acid. Irradiation of this analyte-matrix mixture by a laser results in the
vaporization of the matrix, which carries the analyte with it. The matrix plays a key role in this
technique. The co-crystallized sample molecules also vaporize, but without having to directly
absorb energy from the laser. Molecules sensitive to the laser light are therefore protected from
direct UV laser excitation.

28. Fast Atom Bombardment (FAB)
Immobilized matrix is bombarded with a fast
beam of Argon or Xenon atoms. Charged
sample ions are ejected from the matrix and
extracted into the mass
analyzers
Used for large compounds with low volatility (eg
peptides, proteins, carbohydrates)
Solid or liquid sample is mixed with a non-
volatile matrix (eg glycerol, crown
ethers, nitrobenzyl alcohol)

29. Electron Ionization (EI)
Energetic process a heated filament emits electrons which are
accelerated by a potential difference of usually 70eV into the sample
chamber.
Ionization of the sample occurs by removal of an electron from the
molecule thus generating a positively charged ion with one unpaired
electron.
•Produces M+.radical cation giving molecular weight
•Produces abundant fragment ions

30. Chemical Ionization (CI)
process is initiated with a reagent gas such as
methane, isobutane, or ammonia, which is ionized by
electron impact.
High gas pressure in the ionization source is required
for the reaction between the reagent gas ions and
reagent gas neutrals.
possible mechanism
Reagent (R) + e
-
→ R
+
+ 2 e
-
R
+
+ RH → RH
+
+ R
RH
+
+ Analyte (A) → AH
+
+ R
biologically important molecules
(sugars, amino acids, lipids etc.).

31. Thermal ionization (TI)
Samples are deposited on rhenium or tantalum filament
and then carefully evaporated and sent to mass analyzer.
used to
•quantify toxic trace elements in foods.
•measurement of stable isotope ratio of
inorganic elements.

32. Accuracy
The range over
which a mass
spectrometer
analyzer can
operate.
A measure of
how well a
mass
spectrometer
separates
ions of
different mass
is a measure of
how close the value
obtained is to the
true value. The
accuracy varies
dramatically from
analyzer to
analyzer depending
on the analyzer
type and resolution.
Mass Range Resolution
Scan Speed
Mass Analyzer
Properties of mass Analyzer
Analyzers
are scanned
with a
regular cycle
time from
low to high
m/z or vice
versa.

33. Mass Analyzer
•Quadrupoles
•Quadrupole Ion Trap
•Linear Ion Trap
•Double-Focusing Magnetic Sector
•Quadrupole Time-of-Flight Tandem MS
•Quadrupole Time-of-Flight MS

34. Quadrupoles
-ions travel parallel to four rods
-opposite pairs of rods have
rapidly alternating potentials
(AC)
-ions try to follow alternating
field in helical trajectories
-stable path only for one m/z
value for each field frequency
Smalll and low cost
Rmax~ 500
Harder to push heavy molecule -m/zmax < 2000

35. Quadrupole Ion Trap
The quadrupole ion trap typically consists of a ring electrode and two hyperbolic endcap
electrodes. The motion of the ions induced by the electric field on these electrodes allows ions
to be trapped or ejected from the ion trap. In the normal mode, the radio frequency is scanned
to resonantly excite and therefore eject ions through small holes in the endcap to a detector. As
the RF is scanned to higher frequencies, higher m/z ions are excited, ejected, and detected.

36. Linear Ion Trap
The linear ion trap differs from the 3D ion trap as it confines ions along the axis of a
quadrupole mass analyzer using a two-dimensional (2D) radio frequency (RF) field
with potentials applied to end electrodes. The primary advantage to the linear trap
over the 3D trap is the larger analyzer volume lends itself to a greater dynamic ranges
and an improved range of quantitative analysis.

37. Double-Focusing Magnetic Sector
the ions are accelerated into a magnetic field using an electric field. A charged particle
traveling through a magnetic field will travel in a circular motion with a radius that depends on
the speed of the ion, the magnetic field strength, and the ion’s m/z. A mass spectrum is
obtained by scanning the magnetic field and monitoring ions as they strike a fixed point
detector.

38. Quadrupole Time-of-Flight Tandem MS
Time-of-flight analysis is based on accelerating a group of ions to a detector where
all of the ions are given the same amount of energy through an accelerating
potential. Because the ions have the same energy, but a different mass, the lighter
ions reach the detector first because of their greater velocity, while the heavier
ions take longer due to their heavier masses and lower velocity. Hence, the
analyzer is called time-of-flight because the mass is determined from the ions’ time
of arrival. Mass, charge, and kinetic energy of the ion all play a part in the arrival
time at the detector.

39. Quadrupole Time-of-Flight MS
Quadrupole-TOF mass analyzers are typically coupled to
electrospray ionization sources and more recently they have
been successfully coupled to MALDI. It has high
efficiency, sensitivity, and accuracy as compared to
Quadrupole and TOF analyzer.

40. Photomultiplier Conversion Dynode
Faraday Cup
Array Detector
Charge (or Inductive) Detector
Electron Multiplier
Detectors used in mass spectrometer

41. Faraday Cup
A Faraday cup involves an ion striking
the dynode (BeO, GaP, or CsSb)
surface which causes secondary
electrons to be ejected. This temporary
electron emission induces a positive
charge on the detector and therefore a
current of electrons flowing toward the
detector.
not particularly sensitive
offering limited amplification of signal
is tolerant of relatively high pressure.
–Ions are accelerated toward a grounded “collector electrode”
–As ions strike the surface, electrons flow to neutralize charge, producing a small
current that can be externally amplified.
–Size of this current is related to # of ions in
–No internal gain → less sensitive

42. Photomultiplier Conversion Dynode
is not as commonly
Life limit is high as compared to others.
the secondary electrons strike a phosphorus
screen instead of a dynode. The phosphorus
screen releases photons which are detected by
the photomultiplier. Photomultipliers also
operate like the electron multiplier where the
striking of the photon on scintillating surface
results in the release of electrons that are then
amplified using the cascading principle.

43. Array Detector
detects ions according to their different m/z, has
been typically used on magnetic sector mass
analyzers.
The primary advantage of this approach is that,
over a small mass range, scanning is not
necessary and therefore sensitivity is improved.

44. Charge (or Inductive) Detector
Charge detectors simply recognize a
moving charged particle (an ion) through
the induction of a current on the plate as
the ion moves past
Detection is independent of ion size.

45. Mass spectrometer
Electron Multiplier
•Most important part
•made up of a series (12
to 24) of aluminum oxide
(Al2O3) dynodes
•Used for increasing
potential
Ions strike the first dynode surface causing an
emission of electrons. These electrons are then
attracted to the next dynode held at a higher
potential and therefore more secondary
electrons are generated.

46. Mass spectrometer
Vacuum in the Mass Spectrometer
All mass spectrometers need a
vacuum to allow ions to reach
the detector without colliding
with other gaseous molecules
or atoms. If such collisions did
occur, the instrument would
suffer from reduced resolution
and sensitivity.

47. Mass spectrometer
Structural analysis and Fragmentation Patterns
•Molecular ion (Parent ion)
•Fragmentation peaks
•Base peak
•Isotopic peaks
.
Mass spectrum
Graph of ion intensity
(relative abundance)
along x-axis versus
mass-to-charge ratio
(m/z) (units
daltons, Da) along Y-
axis

48. Mass spectrometer
Molecular ion (Parent ion)
the peak corresponding
to the mol wt of the
compound
The peak of an ion
formed from the original
molecule by electron
ionization, by the loss of
an electron, or by
addition or removal of
an anion or cation and
also known as parent
peak, radical peak.

49. Mass spectrometer
Fragmentation peaks
The peaks observed by fragments of
compounds.
The molecular ions are energetically
unstable, and some of them will break up
into smaller pieces. The simplest case is
that a molecular ion breaks into two
parts -one of which is another positive
ion, and the other is an uncharged free
radical.
The uncharged free radical won't produce a line on the mass
spectrum. Only charged particles will be accelerated, deflected and
detected by the mass spectrometer. These uncharged particles will
simply get lost in the machine -eventually, they get removed by the
vacuum pump.

50. Base peak
The most intense (tallest) peak in a mass spectrum, due to the
most abundant ion. Not to be confused with molecular ion: base
peaks are not always molecular ion and molecular ion are not
always base peaks.

51. Fragmentation Patterns
By using fragmentation pattern we can easily study the structure of
a compound.
Stevenson’s Rule
Homolytic bond cleavage
Heterolytic fragmentation
Alpha cleavage
Beta-cleavage
Inductive cleavage
Retro Diels-Alder Cleavage
McLafferty rearrangement
Ortho effect
Onimum Reaction
CO Elimination

52. Stevenson’s Rule
The most probable fragmentation is the one that leaves
the positive charge on the fragment with the lowest
ionization energy
In other words, fragmentation processes that lead to the
formation of more stable ions are favored over
processes that lead to less-stable ions.
Cleavages that lead to the formation of more stable
carbocations are favored. When the loss of more than
one possible radical is possible, a corollary to
Stevenson’s Rule is that the largest alkyl radical to be
lost preferentially.

53. Homolytic bond cleavage
A type of ion fragmentation in which a bond is broken by
the transfer of one electron from the bond to the charged
atom, the other electron remaining on its starting atom.
The movement of one electron is signified by a fishhook
arrow. The fragmentation of a ketone is shown in the
figure.

54. Heterolytic bond cleavage
type of ion fragmentation in which a bond is broken by
the transfer of a pair of electrons from the bond to the
charged atom
The movement of 2 electrons is signified by a double-
barbed arrow and also referred to as charge-induced
fragmentation.

55. Alpha cleavage
For example in alcohols, aliphatic ethers, aromatic ethers, cyclic
compounds and aromatic ketones etc.
Alpha cleavage occurs on α-bonds adjacent to
heteroatoms (N, O, and S). Charge is stabilized by
heteroatom. Occurs only once in a fragmentation
(cation formed is too stable to fragment further)

56. Beta-cleavage
Fission of a bond two removed from a heteroatom or
functional group, producing a radical and an ion. Also
written as β-cleavage. For example allylic fragmentation.

57. Inductive cleavage
If an electron pair is completely
transferred towards a centre of
positive charge as a result of the
inductive effect, shown
schematically by the use of a
double-headed arrow, then the ion
will fragment by inductive
cleavage. The figure illustrates
this for a radical cation ether.

58. Retro Diels-Alder Cleavage
A multicentered ion fragmentation which is the
reverse of the classical Diels-Alder reaction
employed in organic synthesis that forms a cyclic
alkene by the cycloaddition of a substituted diene
and a conjugated diene. In the retro reaction, a
cyclic alkene radical cation fragments to form
either a diene and an alkene radical cation or a
diene radical cation and an alkene. Depending on
the substituents present in the original
molecule, the more stable radical cation will
dominate.

59. McLafferty rearrangement
An ion fragmentation characterised by a
rearrangement within a six-membered ring
system. The most usual configuration is for a
radical cation formed by EI to undergo the
transfer of a γ-hydrogen atom to the ionisation
site through a ring system as shown here.
The distonic radical cation so formed can break up by radical-
site-induced (α), or charged site-induced fragmentation as
shown in the figure. For example ketones, carboxylic acid and
esters.

60. Ortho effect
The interaction between substituents oriented ortho, as opposed to para
and meta, to each other on a ring system, can create specific
fragmentation pathways. This permits the distinction between these
isomeric species. The diagram shows a case in which only the ortho
isomer can undergo the rearrangement.

61. Onium Reaction
Mostly observed in cationic fragments containing
a heteroatom as charge carrier, e.g.
oxonium, ammonium, phosphonium and
sulphonium ions.
The onium reaction is not limited to alkyl
substituents
acyl groups can also undergo the
onium reaction
Onium Ion: A hypervalent species
containing a non-metallic element such
as the methonium ion CH5+. It includes
ions such as
oxonium, phosphonium, and nitronium
ions.

62. CO Elimination
If there is more than one CO group present
sequential elimination of all CO
groups is possible.
From carbonyl compounds CO elimination reaction
takes place like in aldehyde, ketones and phenols
etc
Cyclic unsaturated carbonyl compounds and
cationic carbonyl fragments
which resulted from an a-cleavage tend to
eliminate CO .

63. Rules for interpretation of mass spectrum
•DBR Calculations
•Nitrogen Rule
•Isotopic effect

64. Double bond or ring calculations tell us about how many rings or double
bonds are present in a compound.
DBR= C-H/2+N/2+1
C= number of carbon atoms
H= number of hydrogen atoms
N= number of nitogen atoms
DBR Calculations

65. Nitrogen Rule
•If a compound contains an even number of nitrogen atoms (or no
nitrogen atoms), its molecular ion will appear at an even mass number.
• If, however, a compound contains an odd number of nitrogen
atoms, then its molecular ion will appear at an odd mass value.
• This rule is very useful for determining the nitrogen content of an
unknown compound.

66. Isotopic effect

67. Mass spectra (examples)
Alkanes
Strong M+ (but intensity decreases with an increase of branches.
Carbon-carbon bond cleavage
loss of CH units in series: M-14, M-28, M-42 etc

68. Alkanes

69. Cycloalkanes
Strong M+, strong base peak at M-28 (loss of ethene)
A series of peaks: M-15, M-28, M-43 etc
Methyl, ethyl, propyl with an additional hydrogen give peaks

70. Alkenes
Strong M+
Fragmentation ion has formula CnH2n+ and CnH2n-1
-Cleavage
A series of peaks: M-15, M-29, M-43, M-57 etc

71. Alkynes
Strong M+
Strong base peak at M-1 peak due to the loss of terminal hydrogen
Alpha cleavage

72. Aromatic Hydrocarbons
Strong M+
Loss of hydrogen gives base peak
McLafferty rearrangement
Formation of benzyl cation or tropylium ion

73. Alcohols
M+ weak or absent
Loss of alkyl group via a-cleavage
Dehydration (loss of water) gives peak at M-18

74. Phenols
Strong M+
M-1 due to hydrogen elimination
M-28 due to loss of CO
M-29 due to loss of HCO (formyl radical)

75. Ethers
M+ weak but observable
Loss of alkyl radical due to a-cleavage
B-cleavage( formation of carbocation fragments through loss of alkoxy radicals)
C-O bond cleavage next to double bond
Peaks at M-31, M-45, M-59 etc

76. Aldehyde
M+ weak, but observable (aliphatic)
Aliphatic : M-29, M-43 etc
McLafferty rearrangement is common gives the base peak
A-cleavage
B-cleavage

77. M+ strong (aromatic)
Aromatic: M-1 (loss of hydrogen)
M-29 (loss of HCO)
McLafferty rearrangement is common
A-cleavage
B-cleavage
Aldehyde

78. Ketones
Strong M+
A series of peaks M-15, M-29, M-43 etc
Loss of alkyl group attached to the carbonyl group by a-cleavage
Formation of acylium ion (RCO+)
McLafferty rearrangement

79. Esters
M+ weak but generally observable
Loss of alkyl group attached to the carbonyl group by a-cleavage
Formation of acylium ion (RCO+)
McLafferty rearrangement
Acyl portion of ester OR+
Methyl esters: M-31 due to loss of OCH3
Higher esters: M-32, M-45, M-46, M-59, M-60, M-73 etc

80. Carboxylic acids
Aliphatic carboxylic acids:
M+ weak but observable
A-cleavage on either side of C=O
M-17 due to loss of OH
M-45 due to loss of COOH
McLafferty rearrangement gives base peak

81. Aromatic carboxylic acids:
M+ Strong
A-cleavage on either side of C=O
M-17 due to loss of OH
M-18 due to loss of HOH
M-45 due to loss of COOH
McLafferty rearrangement gives base peak

82. Amines
M+ weak or absent
Nitrogen rule obey
A-cleavage

83. Nitriles
M+ weak but observable
M-1 visible peak due to loss of termiminal hydrogen

84. Nitro Compounds
M+ seldom observed
Loss of NO+ give visible peak
Loss of NO2+ give peak

85. Alkyl chloride and alkyl bromides
Strong M+2 peak
For Cl M/M+2 = 3:1
F or Br M/M+2 = 1:1
A-cleavage
Loss of Cl or Br
Loss of HCl or HBr

86. Alkyl chloride

87. Applications of Mass Spectrometry
The technique has both quantitative and qualitative
uses. These include identifying unknown compounds,
determining the isotopic composition of elements in a
molecule, and determining the structure of a
compound by observing its fragmentation. Followings
are the main applications
Toxicity of Toothpastes
Measuring nanoparticle size
Pharmacokinetics
Protein characterization
Space exploration
Isotope dating and tracking
Molecular weight
Bonding
Reaction mechanism

88. Toxicity of Toothpastes
DEG (diethylene glycol) which is a toxic chemical and usually present in
Chinese toothpastes.
Measuring nanoparticle size
Mass spectrometry is used to measure nanoparticle size like platinum
nanoparticles which is used as catalyst.
Once size of a sphere is measured, its density is also calculated.
Pharmacokinetics
Pharmacokinetics is often studied using mass spectrometry because of the
complex nature of the matrix (often blood or urine) and the need for high
sensitivity to observe low dose and long time point data.

89. Protein characterization
Mass spectrometry is an important emerging method for the
characterization of proteins. The two primary methods for ionization of
whole proteins are electrospray ionization (ESI) and (MALDI).
Space exploration
Mass spectrometers are also widely used in space missions to measure the
composition of plasmas. For example, the Cassini spacecraft carries the
Cassini Plasma Spectrometer (CAPS),
[44]
which measures the mass of ions
in Saturn's magnetosphere.
Isotope dating and tracking
Mass spectrometry is also used to determine the isotopic composition of
elements within a sample. Differences in mass among isotopes of an
element are very small, and the less abundant isotopes of an element are
typically very rare, so a very sensitive instrument is required. These
instruments, sometimes referred to as isotope ratio mass spectrometers
(IR-MS).

90. Molecular weight
Molecular weight can be determined by mass spectrometry.
Actual number of carbons, hydrogen, oxygen etc
By using relative intensities(peak hight), we can easily calculated the actual
numbers of C,H,O etc atoms.
Bonding
Bonding can be studied by fragmentation patterns for example, beta
cleavage is possible only if double bonds or heteroatom present.
Reaction mechanism
Mass spectrometry is best technique to study reaction mechanism and
intermediates produced in reaction, for example, in carboxylic acid and
alcohols a peak at M-18 indicates that water is produced.

91. Determination of Elements
Bulk materials such as steel or refractory
metals, elements are determined by low-
resolution glow-discharge mass spectrometry.
High-resolution GDMS has been used to study
semiconductor materials. GDMS is considered
virtually free of matrix effects.
Detection limits in ICPMS as in Table

92. Species Analysis
Heavy metals in the environment are stored in complexes with
humicacids, can be converted by microbes in different
complexes, and can be transported in live animals and humans.
This applies to many elements such as
lead, mercury, arsenic, astatine, tin and platinum
For example, tin and lead alkylatesestablished in
soil, water or muscle tissue by GC / MS after exhaustive
alkylation or thermal spray, and ICP-LC/MS API methods.

93. Environmental Chemistry
the analysis of trace elements and compounds
in environmental samples like air, water, soil etc
because of its detection power, specificity and
structural analysis functions
Generally, sample preparation is at least one
type of chromatography coupled with MS either
offline or online like GCMS

94. References
Dictionary of Mass Spectrometry, A.I. Mallet and S. Down, 2009
Introduction to spectroscopy, Donald L. Pavia
Hand book of spectroscopic data, B.D.Mistry.
Comprehensive analytical chemistry.
. Handbook of Spectroscopy, by G. Gauglitz and T. Vo-Dinh
Instant notes of Analytical chemistry, D.Kealey.
Modern Analytical Chemistry, David Harvey.
The Basics of Spectroscopy, David.W.Ball.
Encyclopedia of Analytical Chemistry Applications, Theory and
Instrumentation Edited by R.A.Meyers
Handbook of Analytical Techniques edited by Helmut Giinzler and Alex
Williams 1st Edition 2001
Encyclopedia of Spectroscopy and Spectrometry part 2(M-Z) Edited By
john C. lindon, George E. Tranter and John L. Holmes

95. LOGO
[email protected]