HISTORY,INTRODUCTION,PRINCIPLE

2.  Introduction.
 History.
 Gas chromatography.
 Mass spectrometry.
 Working principle of GC/MS.
 Applications.
 Lab designing.
 Conclusion.

3.  The use of a mass spectrometer as the detector in
gas chromatography was developed during the
1950s by Roland Gohlke and Fred McLafferty.
 First-generation GC/MS would have required at
least 16 minutes.
 The first on-line coupling of gas chromatography to
a mass spectrometer was reported in 1959.
 A bulky, fragile device.
 In 1996 the top-of-the-line high-speed GC-MS units
completed analysis of fire accelerants in less than 90
seconds.

4. DEFINITON:
• An Hybrid technique which couples
the powerful separation potential of
gas chromatography with the
specific characterization ability of
mass spectroscopy.
“GAS CHROMATOGRAPHY-MASS
SPECTROMETRY”

5.  Gas chromatography-mass spectroscopy (GC-MS)
is one of the hyphenated analytical techniques.
 It is actually two techniques that are combined to
form a single method of analyzing mixtures of
chemicals.
 Gas chromatography separates the components of a
mixture and mass spectroscopy characterizes each
of the components individually
 Qualitatively and quantitatively evaluate a solution
containing a number of chemicals.

6.  Separation of molecules by distribution between a
stationary phase and a mobile phase.
 A stationary phase (absorbent) phase the
material on which the separation takes place.
can be solid, gel, or liquid. Also called matrix,
resin, or beads.
 The mobile phase is the solvent transports the
sample and it is usually a liquid, but may also
be a gas. Also called eluting buffer.

7. Chromatography

8. WHAT IS GAS CHROMATOGRAPHY?
 The father of modern
gas chromatography
is Nobel Prize
winner John Porter
Martin, who also
developed the first
liquid-gas
chromatograph.
(1950)

9.  GC is a separation technique.
 Sample is usually a complex
mixture, that is separated into
constituent components.
 Why? usually to quantify some
or all components e.g.
Pharmaceuticals, Environmental
pollutants, etc Occasionally as a
qualitative tool .

10.  Hardware to introduce the sample .
 Technique to separate the sample into
components .
 Hardware to detect the individual components.
 Data processing to process this information.

12.  Sample is introduced into system via hot
vaporizing injector.
 Typically 1ul is injected.
 Flow of “Carrier Gas” moves vaporised sample
(i.e. gas) onto column
 Column is coated with wax type material with
varying affinity for components of interest
 Components are separated in the column based on
this affinity.
 Individual analytes are detected as they emerge
from the end of the column through the Detector.

14.  Carrier Gas
 Injector
 Column
 Capillary
 Stationary Phase
 Detectors
 Mass Spectrometer

15.  Inert
 Helium
 Choice dictated by detector, cost, availability
 Pressure regulated for constant inlet pressure
 Flow controlled for constant flow rate
 Chromatographic grade gases (high purity)

16.  Columns Material of Construction
 Metal (1957)
 Glass (1959)
 Fused Silica (1979)
 Aluminium Clad (1984)
 Inert Metal (1990)

17.  Stationary Phases Choice of phase determines
selectivity
 Like dissolves like
 Use polar phases for polar components
 Use non-polar phases for non-polar
components

18.  Internal Diameter
 Film Thickness
 Length
 Phase Column
 Capacity
 The Maximum amount that can be injected without significant
peak distortion
Column capacity increases with :-
 film thickness
 temperature
 internal diameter
 stationary phase selectivity
If exceeded, results in :-
 peak broadening
 Asymmetry
 leading

19.  Flame Ionization Detector
 Photo Ionization Detector
 Electron Capture Detector
 Infrared Detector
 Helium Ionization Detecto

20.  Mass spectrometry (MS) is based on the
production of ions, which are subsequently
separated or filtered according to their mass-to-
charge ( m/z ) ratio and detected.
 The mass to charge ratio (m/ z) is used to
describe ions observed in mass spectrometry.

22.  Extremely powerful tool because it permits direct
and effectively continuous and correlation of
chromatographic and mass spectroscopic
properties .
 The separation and identification of the
components of complex natural and synthetic
mixtures are achieved more quickly than any other
technique with less sample .
 Molecules then undergo electron /chemical
ionization
Ions are then analyzed according to their mass to
charge ratio
 Ions are detected by electron multiplier which
produces a signal proportional to ions detected

24.  Electron multiplier passes the ion current
signal to system electronics
 Signal is amplified
 Result is digitized
 Results can be further processed and displayed

25.  GC is used for SEPERATION of components
 MS/MS operates by selecting target ions of
specific mass
 Separates the ions from selected parent ions by
collision with helium molecules.
 GC/MS/MS provides identification in cases
where GC/MS spectra of compounds are
difficult to interpret.

26.  After separation by gas chromatography , the
ms/ms operates by first selecting the target ion(s)
of choice at a specific mass during the first stage of
ms/ms, which separates the ions from the
chemical background or matrix .
 These selected precursor ions or parent ions are
then induced to further dissociate by collision with
helium molecules.
 The resultant unique product ion spectrum
provides confirmation of the target analyte .
 This increased selectivity of ms/ms also results in
an enhancement of the signal to noise ; thus
somewhat lower limits of detection are achieved.
 Gc/ms/ms provides unequivocal identification in
cases where gc/ms spectra of compounds are
difficult to interpret.

27.  Thus, even if the matrix contains another
compound with the same mass as the parent ion
for the analyte of interest , it is extremely unlikely
that the interfering ion would yield the same
daughter ion spectra as the analyte , thus gc
/ms/ms is more specific for an ignitable liquid.
 In order to overcome the pyrolysis product
interference and improve detection levels, ms/ms
can be utilized as the method of detection.
 As gasoline is one of the more common distillates
used by arsonists, the identification of gasoline in
fire debris samples is important.
 The parent ions and daughter ions are isolated and
the ms/ms chromatograms for a variety of
hydrocarbon distillates are obtained and
subsequently compared to ignitable liquid
standards, run under identical conditions

29. 1. ENVIRONMENTAL MONITORING:
 A highly suggested tool for monitoring and tracking organic pollutants in the
environment.
 The determination of chloro-phenols in water and soil, polycyclic aromatic
hydrocarbons (pah), unleaded gasoline, dioxins, toxicity, organo-chlorine
pesticides, herbicides, phenols, halogenated pesticides, Sulphur in air.
 It can also be used to screen the degradation products of lignin in bio-mass
research, pesticides.

30. 2. FOOD, BEVERAGE, FLAVOR AND FRAGRANCE
ANALYSIS:
 GC-MS is used for the analysis of esters, fatty acids, alcohols,
aldehydes, terpenes etc.
 It is also used to detect and measure contaminants, spoilage
and adulteration of food, oil, butter, ghee that could be
harmful.
 It is used in the analysis of piperine, spearmint oil, lavender
oil, essential oil, fragrance reference standards, perfumes,
chiral compounds in essential oils, fragrances, menthol,
allergens.

31. 3. FORENSIC AND CRIMINAL
CASES:
 It is also commonly used in forensic
toxicology to find poisons, steroids in
biological specimens of suspects, victims, or
the deceased.
4. BIOLOGICALAND PESTICIDES
DETECTIONS:
 This technique could be used for detecting
adulterations, fatty acid profiling in microbes,
presence of free steroids, blood pollutants,
metabolites in serum, oregano-chlorinated
pesticides in river water, drinking water, soft
drinks.

32. 5.MEDICINE AND PHARMACEUTICAL
APPLICATIONS:
 The GCMS is used for determining metabolic activity.
 It is useful to detect oils in creams, ointments, lotion etc.
 It is an integral part of research associated with medicinal chemistry
(synthesis and characterization of compounds), pharmaceutical analysis
(stability testing, impurity profiling), pharmacognosy, pharmaceutical
process control, pharmaceutical biotechnology etc.

33. 6. PETROCHEMICALAND
HYDROCARBONS ANALYSIS:
 Broad range of petrochemicals, fuels and
hydrocarbon mixtures, including gasoline,
kerosene, naphthenic acids, diesel fuel, various oil
types, transformer oil, biodiesel, wax and broad
range of geochemical samples can be analyzed
by GC-MS.
7. INDUSTRIAL APPLICATIONS:
 GC-MS is used in industries for the analysis of
aromatic solvents, inorganic gases, amino alcohol
in water, impurities in styrene, glycol, xylene,
allergens in cosmetics etc.
 GC-MS is used for the characterization of formic
acid in acetic acid for industrial use.

34. 7. ENERGY AND FUELAPPLICATIONS:
 GC-MS is used for the analysis of aromatic solvents, sulphur,
impurities in polypropylene, Sulphur in methane, natural gases, 1,3
butadiene, ethylene, gas oil, unleaded gasoline, polyethene, diesel oil,
unleaded gasoline, polyethylene, diesel, modified biomass, grafted
polymers etc.

35. OBJECT: To check the fatty acids through gas
chromatography-mass spectrometry.

36.  Gas chromatography separates the analytes that is volatile and chemically
stable.
 Fatty acids are not sufficiently volatile for GC-MC analysis so it
chemically need to produce a new compound which has properties that
are suitable for analyses.
 Unsuitable samples introduced into GC-MC analysis, tends to cause peak
tailing due to the adsorption and non-specific interaction with the column.
 In this experiment the fatty acid change to fatty acid methyl Easter
(FAME) that is more volatile, suitable for GC-MC analysis by using
esterification reaction that used metholic solution with catalyst of
esterification reagent.
 The objective for this experiment is to introduce a derivatizative
procedure routinely used for fat analysis in which non volatile fatty acid
are chemically convert to the corresponding volatile methyl ester (FAME)
and to determine the amount of FAME in the derivatized samples.

37.  Injector port: split (40:1)
 Injection port temperature: 250°C
 Column temperature: 100°C to 290°C at 40°C/min
 Carrier gas flow rate: 30Ml/sec
 Detector temperature: 250°C

38.  Each of the derivatized samples was injected into GC-MC column by
using automated injector.
 FAME standard mixture was injected into the GC-MC column.
 The amount of fatty acid in each sample was calculated.

39.  When GC is combined with MS, a
powerful analytical tool is created. A
researcher can take an organic solution,
inject it into the instrument, separate the
individual components, and identify each
of them. Furthermore, the researcher can
determine the quantities (concentrations)
of each of the components after careful
calibration.