Mass spectrometry and gas chromatography are analytical chemistry techniques. Mass spectrometry identifies chemicals by measuring the mass-to-charge ratio of ions to determine molecular weights. Gas chromatography separates mixtures by vaporizing samples and carrying them through a column with an inert gas mobile phase. Different compounds migrate through the column at different rates and are detected to create a chromatogram. These techniques are useful for identifying compounds in mixtures like drugs, metabolites, fibers, and more.

1. Bahir Dar University
First Year M.SC In Textile Chemistry
Seminar on Mass Spectroscopy and Gas Chromatography
Prepared by: Asnake Ketema5/31/2018
Ethiopia Institute of Textile and Fashion Technology (EiTEX

2. Mass Spectrometry
 Analytical method to measure the
molecular or atomic weight of samples

3. 22/12/2017
3

4. DEFINITION:
Mass spectrometry (MS) is an analytical chemistry
technique that helps identify the amount and type of
chemicals present in a sample by measuring the mass- to-
charge ratio and abundance of gas-phase ions.
PRINCIPLE:
A mass spectrometer generates multiple ions from the
sample under investigation
This molecular ion undergoes fragmentation. Each
primary product ion derived from the molecular ion, in
turn, undergoes fragmentation, and so on.

5. The ions are separated in the mass spectrometer
according to their mass-to-charge ratio, and are
detected in proportion to their abundance. A mass
spectrum of the molecule is thus produced.
It displays the result in the form of a plot of ion
abundance versus mass-to-charge ratio

6. 6

8. Gas Chromatography
22/12/2017
8
Gas chromatography (GC) is a common technique for
separating and analyzing components of a mixture.

9. INTRODUCTION
Chromatography:- is a technique for
separating chemical substances that relies on
differences in partitioning behavior between a
flowing mobile phase and a stationary phase to
separate the components in a mixture.
22/12/2017
9

10. Volatility:- high‐vapor pressure or a relatively low
boiling point
Polarity
Mechanisms Of G.C
22/12/2017
10

11. Operational Principle G.C
First- a vaporized sample is injected onto the
chromatographic column.
Second- the sample moves through the
column through the flow of inert gas.
Third- the components are recorded as a
sequence of peaks as they leave the column.
22/12/2017
11

12. Main Components Of G.C
Carrier Gas
supply
Analyst
Instrument control
Data acquisition
Data processing
Data storage
Gas Flow Controller
Data System
OvenColumn
Injection Port
Sample
GC
Detector
22/12/2017
12

13. 1. Carrier gas
2. Flow regulators & Flow meters
3. Injection devices
4. Columns
5. Temperature control devices
6. Detectors
7. Recorders & Integrators
Practical Requirements
22/12/2017
13

14. Chromatographic Separation
• Mobile – inert gas used as carrier.
• Stationary – liquid coated on a solid or
a solid within a column.
22/12/2017
14

15. 22/12/2017
15

16. Chromatographic Analysis
1. The number of components in a sample is
determined by the number of peaks
2. The amount of a given component in a sample is
determined by the area under the peaks.
3. The identity of components can be determined
by the given retention times
22/12/2017
16

17. Conti . . .
Peak area proportional to mass of compound
injected
Peak time dependent on velocity through
column
22/12/2017
17
detector
output

18. Applications Of G.C
1.Separation & identification of lipids, carbohydrates &
proteins.
2. amino acids in urine
3. Measurement of drugs & other metabolites in biological
fluids.
5. Analysis of pesticides in soil, water, food.
7. analysis of blood and urine alcohol levels
8. identify nitro-compounds in trace quantities
22/12/2017
18

19. Advantage Dis-Advantage
 very small samples with
little preparation
 separating complex
mixtures into components
 Results fast(1-100
minutes)
 Very high precision
 Equipment is not very
complex. it can be easily
analysis the data from the
graph.
 Only use volatile
compounds ( which
can be converted in to
vapor
 Dirty samples not give
correct result
22/12/2017
19

20. Pyrolysis Gas Chromatography
When the heat energy applied to the polymer
chains is greater than the energy of specific
bonds in that polymer chain, these bonds will
fragment.
22/12/2017seminar on Gas Chromatography
20

21. Illustrate polymer analysis by G.C
protein samples shown to be useful for analysis of proteins
other than wool fibers by using different special programs
reflecting different amino acid compositions.
acetaldehyde from alanine
isobutyronitrile from valine
22/12/2017
21

22. thermally-denatured samples of wool fiber which
cannot be identified successfully by morphological
inspection using a microscope or by using Fourier-
transform infrared micro spectroscopy.
Conti . .
22/12/2017
22

23. FIBERS - COTTON AND POLYESTER
PET, on the other hand, degrades to
produce aromatics, including
benzene, benzoic acid, and
oligomeric fragments of the polymer
generated from a
piece of cotton thread heated to 750°C
for 15 seconds. When cellulose
degrades thermally,
it produces water and carbon dioxide,
and many
other organic materials, including
aldehydes and ketones.
22/12/2017
23

24. References
22/12/2017
24
Ravi Shankar, text book of pharmaceutical
analysis.
Skoog.D.A, Holler .F.J; principles of instrumental
analysis.
P.C.Kamboj; pharmaceutical analysis- II,
instrumental methods, pg.no: 281-322.
P.D.Sethi; quantitative analysis of drugs; 3rd
edition.
A.V.Kasture; pharmaceutical analysis- volume II.