This document provides information about gas chromatography (GC). GC is a physical method used to separate mixtures by distributing components between a stationary and mobile phase. When the mobile phase is a gas, it is called gas chromatography. Separation occurs in a long column as components travel through at different speeds depending on how strongly they interact with the stationary phase. As components exit the column, a detector produces peaks on a chromatogram to identify each component by the time it elutes. Common stationary phases include liquids coated on an inert solid and solid adsorbents. Mobile phases are usually inert gases like nitrogen or helium. Detectors include the flame ionization detector and thermal conductivity detector. GC allows for quick, precise separation and analysis of small
In this slide contains Interference In Atomic Absorption Spectroscopy and applications.
Presented by: Shaik Gouse ul azam. ( department of pharmaceutical analysis.)
RIPER, anantpur.
introduction
Interference is a phenomena
that leads to changes (either positive or negative) in intensity of the analyte signal in spectroscopy.
Interferences in atomic absorption spectroscopy fall into two basic categories, namely, non-spectral and spectral.
1. spectral 2. Non Spectral ( Matrix interference, chemical interference, ionization interference)
PRINCIPLE - atomic absorpion spectroscopy
Atoms of the analyte have a fixed number of electrons.
If the light of a specific wavelength is passed through a flame containing that atom, electrons present in different energy levels, known as orbitals, absorb a certain wavelength and excite to higher energy levels.
The extent of absorption ά the number of ground-state atoms in the flame.
Only for information- The ground state is more stable than the excited state. The electrons spontaneously return back to the ground state. It emits the same amount of radiant energy. This process is called fluorescence. Fluorescence is used in atomic emission spectroscopy.
Brief note on - Instrumentation
The basic components of atomic absorption are:
Light source
Chopper
Atomizer
Burners
flames
Monochromators
Detectors
Amplifier
Readout devices
WORKING PROCESS
Calibration
Quantitative analysis in AAS
Safety measures
Important questions and answer
Gas chromatography is one of the widely used chromatographic techniques, which use inert gas as the mobile phase.
In gas chromatography the components of a sample, after vaporization, are separated by being partitioned between gaseous mobile phase and solid or liquid stationary phase.
The inert gas does not interfere with the analyte but transport the components through the column and facilitate the separation.
The mobile phase is comprised of an inert gas such as helium, argon or nitrogen.
The stationary phase consists of a packed column in which the packing or solid support, or a liquid coat act as stationary phase.
The main principles involved are adsorption and partition for gas solid chromatography and gas liquid chromatography, respectively.
Gas chromatography and its instrumentationArgha Sen
Gas chromatography is an unique technology which helps us in separating volatile analytes. Its is an easy and reproduciple method for detecting residual solvents found in APIs.
In this slide contains Interference In Atomic Absorption Spectroscopy and applications.
Presented by: Shaik Gouse ul azam. ( department of pharmaceutical analysis.)
RIPER, anantpur.
introduction
Interference is a phenomena
that leads to changes (either positive or negative) in intensity of the analyte signal in spectroscopy.
Interferences in atomic absorption spectroscopy fall into two basic categories, namely, non-spectral and spectral.
1. spectral 2. Non Spectral ( Matrix interference, chemical interference, ionization interference)
PRINCIPLE - atomic absorpion spectroscopy
Atoms of the analyte have a fixed number of electrons.
If the light of a specific wavelength is passed through a flame containing that atom, electrons present in different energy levels, known as orbitals, absorb a certain wavelength and excite to higher energy levels.
The extent of absorption ά the number of ground-state atoms in the flame.
Only for information- The ground state is more stable than the excited state. The electrons spontaneously return back to the ground state. It emits the same amount of radiant energy. This process is called fluorescence. Fluorescence is used in atomic emission spectroscopy.
Brief note on - Instrumentation
The basic components of atomic absorption are:
Light source
Chopper
Atomizer
Burners
flames
Monochromators
Detectors
Amplifier
Readout devices
WORKING PROCESS
Calibration
Quantitative analysis in AAS
Safety measures
Important questions and answer
Gas chromatography is one of the widely used chromatographic techniques, which use inert gas as the mobile phase.
In gas chromatography the components of a sample, after vaporization, are separated by being partitioned between gaseous mobile phase and solid or liquid stationary phase.
The inert gas does not interfere with the analyte but transport the components through the column and facilitate the separation.
The mobile phase is comprised of an inert gas such as helium, argon or nitrogen.
The stationary phase consists of a packed column in which the packing or solid support, or a liquid coat act as stationary phase.
The main principles involved are adsorption and partition for gas solid chromatography and gas liquid chromatography, respectively.
Gas chromatography and its instrumentationArgha Sen
Gas chromatography is an unique technology which helps us in separating volatile analytes. Its is an easy and reproduciple method for detecting residual solvents found in APIs.
In this slide contains principle of IR spectroscopy and sampling techniques.
Presented by: R.Banuteja (Department of pharmaceutical analysis).
RIPER, anantpur.
In this slide contains Factors Affecting Resolution In HPLC and its criteria's.
Presented by: M.Sudheeshna. (Department of pharmaceutical analysis).
RIPER,anantpur.
In this slide contains principle of IR spectroscopy and sampling techniques.
Presented by: R.Banuteja (Department of pharmaceutical analysis).
RIPER, anantpur.
In this slide contains Factors Affecting Resolution In HPLC and its criteria's.
Presented by: M.Sudheeshna. (Department of pharmaceutical analysis).
RIPER,anantpur.
Introduction
Invention of Chromatography
Chromatography
Paper Chromatography
Thin Layer Chromatography (TLC)
Liquid Chromatography (LC)
High Pressure Liquid Chromatography (HPLC)
Ion Chromatography
Gas Chromatography (GC)
Applications of chromatography
Conclusion
Gas chromatography (GC) is an analytical technique used to separate and detect the chemical components of a sample mixture to determine their presence or absence and/or quantities. Slides are prepared by the Students of Pharmacy Department, Southeast University.
Gas Chromatography is an analytical techniques, used for the separation of volatile substances on the basis of their partition coefficient . In this slide you will find out different instrumentation of gas chromatography, its advantages, disadvantages and moreover its applications.
Gas chromatography- “It is a process of separating component(s) from the given crude drug by using a gaseous mobile phase.”
Principle- The principle of separation in GC is “partition.”
The mixture of components to be separated is converted to vapor and mixed with the gaseous mobile phase.
The component which is more soluble in the stationary phase travels slower and eluted later.
The component which is less soluble in the stationary phase travels faster and eluted out first.
No two components have the same partition coefficient conditions.
So the components are separated according to their partition coefficient.
The partition coefficient is “the ratio of solubility of a substance distributed between two immiscible liquids at a constant temperature.’
It involves a sample being vaporized and injected onto the head of the chromatographic column.
The sample is transported through the column by the flow of inert, gaseous mobile phase.
The column itself contains a liquid stationary phase which is adsorbed onto the surface of an inert solid.
Two major types:
1. gas-solid chromatography: Here, the mobile phase is a gas while the stationary phase is a solid.
Used for separation of low molecular gases,
e.g., air components, H2S, CS2, CO2, rare gases, CO, and oxides of nitrogen.
2.Gas-liquid chromatography: The mobile phase is a gas while the stationary phase is a liquid retained on the surface as an inert solid by adsorption or chemical bonding.
Advantages-
Both qualitative and quantitative analyses are possible.
The instrument is simple, time of analysis is short.
High sensitivity.
The method is applicable to about 60% of organic compounds.
Very small sample sizes can be used.
Analysis can be highly accurate and precise.
Applications-
Quality control and analysis of drug products like antibiotics (penicillin), antivirals (amantadine), general anesthetics (chloroform, ether), sedatives/hypnotics (barbiturates), etc.
Assay of drugs – purity of a compound can be determined for drugs like :
Atropine sulfate
Clove oil
Stearic acid
In determining the levels of metabolites in body fluids like plasma, serum, urine, etc
Estimation of spoilage components, such as histamine and carbonyls, that cause rancidity.
Low amount of sample
Complex mixture.
Gas chromatography is a process of separating component(s) from the given crude drug or mixture by using stationary phase (solid or liquid) and gaseous mobile phase. It involves a sample being vaporized and injected onto the head of the chromatographic
column. The sample is transported through the column by the flow of inert, gaseous
mobile phase. The column itself contains a solid or liquid stationary phase which is adsorbed onto the
surface of an inert solid.
Gas Chromatography in Analytical Analysis.pptxRAHUL PAL
Gas chromatography is a common type of chromatography used in analytical chemistry for separating and analyzing compounds that can be vaporized without decomposition. Typical uses of GC include testing the purity of a particular substance, or separating the different components of a mixture.
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
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Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
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Macroeconomics- Movie Location
This will be used as part of your Personal Professional Portfolio once graded.
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Prepare a presentation or a paper using research, basic comparative analysis, data organization and application of economic information. You will make an informed assessment of an economic climate outside of the United States to accomplish an entertainment industry objective.
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Acetabularia acetabulum is a single-celled green alga that in its vegetative state is morphologically differentiated into a basal rhizoid and an axially elongated stalk, which bears whorls of branching hairs. The single diploid nucleus resides in the rhizoid.
Biological screening of herbal drugs: Introduction and Need for
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Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
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In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
1. GAS CHROMATOGRAPHY
Dr. S. H. Burungale
Head Department of Chemistry
Yashwantrao Chavan College of Science,
Karad-415124
2. GAS CHROMATOGRAPHY(GC)
Chromatography is a physical method of
separation and analysis. Contrast to chemical
methods, this method is very quick, can be used
with very small quantity of sample and the analysis
can be done with high accuracy and precision.
3. In chromatography, the components of a
mixture are distributed between two phases : (1)
Stationary phase having large surface area (a
porous silica or liquid coated on inert porous solid)
and (2) mobile phase (a gas or liquid) which
moves continuously in contact with stationary
phase.
4. When the mobile phase is gas, it is termed
as gas chromatography and depending on the
stationary phase used, it is either Gas-solid
chromatography (GSC) or Gas-liquid
chromatography (GLC).
5. In, GC elution method of development is
used. Here inert mobile phase gas, is kept flowing
continuously in contact with stationary phase in
column. The components of sample either as
mixture or partially separated are transported from
one end of the column to the other end of column.
6. In GC, the stationary phase either finely
divided solid or liquid coated on inert solid is tightly
packed in a column with narrow bore. It is 3 to 5
meter long. Column is kept in an oven maintained
at constant temperature. A carrier gas which is
relatively inert like N2, Ar, H2 or He is introduced
through one end and is kept constantly flowing in
the column.
Principle of GC Separation
7. A sample is introduced at a point which is
few centimeters away from entrance point of
carrier gas. If liquid mixture of sample is introduced
it is instantly vaporised in a heated port and
inserted as a sharp plug.
8. When the components of a mixture carried by
carrier gas comes in contact with solid stationary
phase, it gets adsorbed. Adsorption occurs
according to the Freundlich adsorption isotherm;
x/m = KC1/n or
The Langmuir adsorption isotherm
x/m =
C
K
C
K
2
1
1
9. Where x is amount of solute getting
adsorbed on m gm of stationary phase, C is
concentration of solute in gaseous state and all K
are constants. n is integer.
If stationary phase is liquid the solute gets
dissolved and Henry's law is followed
x/m = KC
10. Both the phenomenon are selective. K
values are different for different solutes on the
same sorbent and hence different amount of solute
is going to stationary phase. An equilibrium is
established between the solute on stationary
phase and solute in mobile phase.
11. As mobile phase is constantly flowing, the
amount of solute not adsorbed is swept away with
mobile phase and to maintain the equilibrium and
K value, out of the swept amount of solute, some
will be adsorbed on the next point again to
maintain K value. This adsorption and desorption
keeps on going successively at every point in the
column.
12. Now components having different K value on
that stationary phase, will be retained on column
differently and hence each solute will travel with
different speed. Each solute follows a Guassian
distribution and travels with the shape of a peak.
As the length of column is quite large, each solute
will come out of the column at different time.
13. If a suitable detector is kept at the other end
of column, then as soon as solute enters it, a
signal will be obtained which is fed to recorder. On
recorder the peak for each solute appears at
different time, and the graph showing multitude of
peaks called Chromatogram is obtained.
16. Mobile phase used in GC
Depending on the mixture to be separated
and detector used, an inert gas like N2, Argon, H2
or He is used as carrier gas. Generally with FID,
N2 or Argon is used and with TCD H2 or He is
used.
17. Sample introduction system
A liquid sample in microlitre quantity is
introduced using hypodermic syringe, while
gaseous sample is introduced with gas tight
syringe or using gas sampling valve.
18. In GC separation occurs in gaseous state
and hence the liquid sample introduced has to be
vaporised instantly. Injection port is therefore kept
heated at a temperature above the highest boiling
point of a component of a mixture.
19. Column
It is considered to be heart of GC, where
separation occurs. Columns are of 3 types.
(1) Packed columns
(2) Wall coated open tubular columns (WCOT)
(3) Support coated open tubular columns (SCOT)
20. Packed columns are of 3 to 5 m length with
internal diameter of 1.5 to 6 mm. Here stationary
phase solid or inert solid on which liquid stationary
phase is coated is packed as micron sized
particles.
(1) Packed columns
21. WCOT is called a capillary column which is
having length of 10-100 m. with internal diameter
0.2 to 0.8 mm. Here liquid stationary phase is
directly coated on wall. Due to extra length, any
complex mixture can be separated with good
resolution. As there is no packing inside, the
carrier gas does not suffer any resistance and
separation is very fast. Its drawback is that, it
cannot accommodate more sample.
(2) Wall coated open tubular columns
22. SCOT has length 10-25 m. and internal
diameter 0.5 mm. Here liquid stationary phase is
coated on micron size layer of inert solid. With
similar advantages of WCOT, more sample can be
loaded on this column.
(3) Support coated open tubular columns
23. GSC has solid stationary phase. Solid
stationary phase used are activated carbon, silica
gel, alumina or molecular sieves. GSC has very
limited applications. It is used to separate
permanent gases and low molecular weight
hydrocarbons. GSC has drawback that due to non
linear adsorption isotherms, peaks show trailing.
24. Use of porous polymer as stationary phase is
important. Divinyl benzene and styrene are
copolymerised under controlled condition to give
porous beads of polymer. Many times a polar liquid
monomer is incorporated to give porous polymer
with definite polarity. Such polymers are
manufactured and available with trade name of
“Porapaks”. They are available with different
polarity and termed as Porapak-P, Q, R,S,N and T.
25. Some separations using porous polymers
are unique. (1) Separation of a mixture of reactive
gases like Cl2, HCl, HCN etc. (2) Separation of a
mixture of formaldehyde, water and methanol.
(3) Mixture of ethylene, ethane, acetylene.
Recently polymer lined open tubular columns
(PLOT) which is 30 m long and ID 0.53 mm. is
introduced. It can separate a mixture of air,
methane, CO2, ethylene, ethane.
26. GLC is more used than GSC due to certain
reasons.
(1) It can be used to separate high molecular
weight liquids.
(2) It is faster than GSC.
(3) The peaks do not show trailing and they are
symmetrical peaks.
(4) Wide choice of liquid stationary phase.
Gas Liquid Chromatography (GLC)
27. The liquid stationary phase is coated on inert
solid. Such inert solid particles are uniformly
shaped, sized and have size less than 10 µm.
Most widely used inert solids are
diatomaceous earths. They are skeletal
remains of the unicellular algae known as
diatoms.
(i) white diatomaceous earths
(ii) pink diatomaceous earths.
28. They differ in method of preparation. They
are manufactured by John-Manville Corp. under
trade name of Chromosorb-W, Chromosorb-P.
Besides these, teflon, glass beads,etc. are used
but not have become popular.
Liquid stationary phase used should be non
volatile at operating temp. of column, should not
be viscous, and should be suitable for the
components to be separated.
29. Most widely used liquid stationary phases
with their temperature limits and applications are
given below.
They are classified as;
(1) Nonpolar
(2) Polar
(3) Intermediate polar etc.
31. Generally to separate polar solutes, polar
liquids are used and to separate non-polar solutes,
non-polar liquids are used as stationary phase.
Liquid stationary phase is dissolved in
volatile solvents, mixed with inert solid support in
definite proportion and then volatile solvent
removed by evaporation, when liquid stationary
phase gets coated on inert solid support.
32. It is then filled in a column to get a packed
column. Generally ready made columns are
purchased from skilled manufacturer.
Columns are kept in oven which is heated
electrically. Its temperature is controlled
electronically.
33. Most widely used detectors are;
(1) Thermal conductivity detector (TCD)
(2) Flame ionisation detector (FID)
(3) Thermionic detector (TID)
(4) Electron capture detector (ECD)
(5) Flame photometric detector (FPD) and
(6) Sulphur chemiluminiscence detector (SCD)
The first two detectors being very common will
not be discussed. Only their comparison is given.
Detectors
34. TCD FID
It responds to all compounds. It is
universal detector.
It responds only to organic compounds
and does not respond to NH3, H2O,
H2S, nitrogen oxides, sulphur oxides
etc.
It is less sensitive than FID. It is more sensitive than TCD.
Its sensitivity depends on flow rate of
carrier gas.
Its sensitivity does not depend upon
flow rate of carrier gas.
It is non destructive detector and hence
suitable with preparative GC.
It is destructive detector and can not be
used with preparative GC.
Here carrier gas used are He or H2. Here N2 or Ar used as carrier gas.
35. It is modified FID. It is selective for
phosphorous and nitrogen containing compounds.
Compared to FID, this detector is 500 times more
sensitive for P compounds and 50 times more
sensitive to N compounds. It is useful for detection
and measurement of P containing pesticides.
Thermionic Detector (TID)
37. It is similar to FID, but in addition it contains an
electrically heated rubidium silicate bead near
collector electrode, which is maintained at about
180 V with respect to collector electrode. The hot
gases then flow around the bead. The heated bead
forms a plasma (gaseous conducting mixture
containing ions) having temperature 6000 to 8000C.
In this plasma, N & P compounds form large no. of
ions, to give large current, and high sensitivity.
38. This is a selective detector which is used for
phosphorous and sulphur containing compounds.
Its construction differs from FID. Like FID it
does not contain the collector electrode around the
flame and does not measure the amount of
ionisation. Instead it measures the radiation
emitted by the flame by the sample components.
For this it contains a photomultiplier tube with
suitable filters. It is shown in the diagram.
Flame photometric detector (FPD)
39. When the eluent is passed in low
temperature hydrogen-air flame, phosphorous
converts to HPO species which emits radiation
centered about 510 and 526 nm.
Sulphur simultaneously is converted to S2
species which emits radiation centered at 394 nm.
Desired wavelength is isolated by using a filter
between the flame and photomultiplier tube.
40. It can also be used to detect halogens,
nitrogen compounds and organometallic
compounds containing metal chromium, selenium
and germanium.
For sulphur compounds, sulphur
chemiluminescence detector (To be described
later) provides greater working range and more
sensitivity than FPD.
42. It is the recent addition, to the family of
detectors used in GC.
It is based upon the reaction between certain
sulphur compounds and ozone. The reaction
produces luminescence and the intensity of this
chemiluminescence is proportional to the
concentration of sulphur. The detector is
particularly useful for the determination of
pollutants such as mercaptans.
Sulphur Chemiluminiscence Detector (SCD)
43. In SCD, the eluent is mixed with hydrogen
and air and is burned as in FID. The resulting
gases are then mixed with ozone and the intensity
of resulting luminescence is measured.
For sulphur compounds, it offers very high
sensitivity and more linear working range.
44. Temperature of column is very important in
separation, as the partition coefficient of the solute
between the two phases much depends on
temperature. As column temperature increases,
the sample spends more time in mobile phase.
This results in decreasing retention time. (Time for
which solute remains in the column). Opposite to
that at lower column temperature, the solute is
retained more on stationary phase and retention
time increases.
Temperature Programming
45. If a complex mixture is to be analysed in which
solute components have a large difference in boiling
point, then the separation at constant column
temperature (isothermal mode) can create
difficulties. At low column temperature, the lower
boiling solutes are well resolved and eluted in
reasonable time but the higher boiling solutes take
long time to elute and few may not come out of the
column. To decrease the retention time of higher
boiling solutes, if column temperature is taken high
then lower boiling solutes are eluted so quickly that
they are not properly resolved.
46. This problem can be overcome by using
temperature programming. In this technique initially
the column is kept at low temperature, and then its
temperature is raised in a programmed manner at
desired heating rate like 50C/min, 100C/min etc.
When the column is at low temperature, the lower
boiling solutes eluted effectively, while the higher
boiling solutes remain condensed on the column.
As the temperature is gradually raised, they start
evaporating from column and elute in the order of
their boiling points.
47. To do temperature programming, initial
temperature, desired heating rate and final
temperature are set on electronic controls. Many
gas chromatographs have facility for this.
48. Though very efficient separation and
analytical technique, GLC has limitation that it
cannot be used for separation of non volatile liquids
and solids. Liquids having maximum boiling point
2500C can be separated with GLC. Nonvolatile
liquids or solids, if desired to be separated by GC,
they have to be converted to their volatile
derivatives. This is called derivatisation.
Derivatisation
49. The reaction used to prepare volatile
derivatives of non-volatile compounds, must be
simple, fast and quantitative even at very low
concentrations encountered with GLC. A few
reagents used to prepare volatile derivatives for
different class of compounds have been listed
below.
51. Head Space Gas Chromatography
Due to very sting quality control parameters
needed in finished products, to be exported, it
becomes essential to find percentage of volatiles
in finished products (solid or liquid) e.g. impurity of
solvent or PCB, in solid or liquid has to be
determined. For this HSGC is used.
52. The measured quantity of product is taken in
an injection vial and sealed. It is kept in a heated
port where volatiles are evaporated and collected
in head space. A syringe needle is inserted in
rubber cap of vial and vapours collected from head
space, are sucked in syringe. It is then removed
and gases from syringe are introduced in injection
port of GC and analysed. All operations are
performed by a robot.
53. GC-interfaced with Mass Spectrometer
Though GC is very useful in quantitative
analysis, qualitative analysis using GC is almost
impossible.
In research, when a plant extract is analysed
by GC, to identify each organic compound
obtained from it, GC is interfaced with MS.
54. Each component separated is undergoing
fragmentation pattern and mass spectra obtained,
the unknown can be identified. Here again
computer acquisition data makes the things very
simple.
55. Modern Elemental Analyser
Modern elemental analyser to determine
percent of C, H and N in organic compound,
simultaneously, principle of GC is used.
A tin crucible containing exact weighed
quantity of organic compound, is dropped in a
furnace heated at 9500C. A flow of oxygen is
introduced. C, H & N are converted to CO2, H2O &
NOx respectively.
56. The mixture passed over copper gauze
when, NOx are converted to N2. This mixture of
CO2,H2O and N2 is then led to a chromatographic
column filled with porapak, where they are
separated and detected by TCD. From percent of
CO2, H2O and N2, percent of C, H and N can be
determined. It has following advantages.
• Hardly 2-5 mg substance needed.
• Percentage of element determined within
5 minute with excellent accuracy.