Atomic absorption spectroscopy is a technique for determining the concentration of a particular metal element in a sample. Atomic absorption spectroscopy can be used to analyze the concentration of over 62 different metals in a solution.

2. ATOMICABSORPTION
SPECTROSCOPY

3. CONTENTS
 History
 Introduction to Atomic Absorption
Spectroscopy
 Principle of Atomic Absorption
Spectroscopy (AAS)
 Instrumentation.
 Applications.

4. HISTORY
• The beautiful phenomenon of “RAINBOW”
was the first dispersed spectrum.
• In 1665 NEWTON took the first and the most important
step towards the development of spectroscopy.
• In 1859 G.R KIRCHOFF and R BUNSEN emerged as the
FATHER OF MODERN SPECTROSCOPY.

5. ABSORPTION SPECTROSCOPY
It gives the measurement of absorbed energy by the atom or
molecule after which it excite and gives the absorbed energy in
the form of absorption spectrum

6. ATOMIC ABSORPTION
SPECTROSCOPY
• Atomic absorption spectroscopy is a technique for determining
the concentration of a particular metal element in a sample.
Atomic absorption spectroscopy can be used to analyze the
concentration of over 62 different metals in a solution.

8. “The atoms of metals are vaporized and their
absorption of radiations produced by Hollow cathode
tube which is made of same metal which is
measured.”
 Atomic Absorption Spectroscopy is a very
common technique for detecting metals and
metalloids in samples.
 It also measures the concentration of
metals in the sample.

9. Atomic
Absorption
spectrometer
Hollow Cathode
Lamp
Nebulizer
AtomizerMonochromator
Detector

12.  Hollow Cathode Lamp are the most common radiation
source in AAS.
 It contains a tungsten anode and a hollow cylindrical
cathode made of the element to be determined.
 These are sealed in a glass tube filled with an inert gas
(neon or argon ) .
 Each element has its own unique lamp which must be
used for that analysis .

13. Hollow Cathode Lamp:
Quartz window
Pyrex
body
Anode
Cathode
cathode

14.  suck up liquid samples at controlled rate.
 create a fine aerosol spray for introduction into flame.
 Mix the aerosol and fuel and oxidant thoroughly
for introduction into flame.

15. Elements to be analyzed needs to be in atomic sate.
Atomization is separation of particles into individual
molecules and breaking molecules into atoms. This is
done by exposing the analyte to high temperatures in a
flame or graphite furnace .

16. ATOMIZER
FLAME
ATOMIZERS
GRAPHITE TUBE
ATOMIZERS

18. FLAME ATOMIZER:
• Flame is used to atomize the sample
• Sample when heated is broken into its atoms
PRINCIPLE:
• High temperature of flame causes excitation
• Electrons of the atomized sample are promoted to
higher orbitals, by absorbing certain amount of
energy
QUANTITATIVE ANALYSIS:
• The amount of energy absorbed is specific for a particular
element (for electronic transition).
• Amount of absorbed radiation is a quantitative measure
for the concentration of the element to be analyzed

19. NEBULIZER
ASSEMBLY
CONVERSION
INTO FINE
MIST & SMALL
DROPLETS OF
SOLUTION
ASPIRATED
INTO SPRAY
CHAMBER
(MIXING
CHAMBER)
AEROSOL
MIXES WITH
COMBUSTION
GASES
FLAME
(ATOMIZATION
OCCURS)

21.  uses a graphite coated furnace to vaporize the sample.
 ln GFAAS sample, samples are deposited in a small
graphite coated tube which can then be heated to
vaporize and atomize the analyte.
 The graphite tubes are heated using a high current
power supply.

22. • serves as sample cell. ( heating
part of the graphite furnace).Graphite tube
• Metal jacket by which the water
is circulated .Enclosed water
cooled housing
• Made of quartz allow light to
pass through the tube.
Transparent
windows
• protect graphite tube from
oxidationInert purge gas
control
• Heating of graphite tube
Electrical contact

23.  This is a very important part in an AA spectrometer. It is
used to separate out all of the thousands of lines.
 A monochromator is used to select the specific wavelength
of light which is absorbed by the sample, and to exclude
other wavelengths.
 The selection of the specific light allows the determination
of the selected element in the presence of others.

24. - Wavelength selectors
- Produces
monochromatic light
Consists of:
1) Entrance slit
2) Diffraction grating
3) Exit slit
Diffraction gratings
are mostly used
rather than prisms

25.  The light selected by the monochromator is directed onto
a detector that is typically a photomultiplier tube , whose
function is to convert the light signal into an electrical
signal proportional to the light intensity.
 The processing of electrical signal is fulfilled by a signal
amplifier . The signal could be displayed for readout , or
further fed into a data station for printout by the requested
format.

26. Used to detect the light
absorbed by the analyte .
The ‘photomultiplier tube’
is used as detector in AAS

27. PHOTO
MULTIPLIER
TUBE
Photoca
thode
Dynodes
(electrodes)
Glass
Envelop
Anode
Construction of Photomultiplier Tube

28. Operation of
photomultiplier
tube
• Photo Emission
• Secondary
Emission

29.  When light of less intensity falls on cathode, it causes the emission of
electrons. These electrons are attracted towards the dynode, and strike
at the first dynode D1 resulting the production of photoelectrons which
are accelerated and focused to the next dynode, Thus producing more
electrons to be focused onto the subsequent dynode. Eventually the
electrons are collected at anode. This cascade effect makes this detector
one of the most sensitive detector.
 Normally each photon striking cathode produces 106 to 109 electrons.
The electrical signals of sample are compared with reference for the
detection.
 PMT cannot be used to measure high intensity radiations because of
non-linearity and instability.
Working:

30. ATOMIC ABSORPTION SPECTROSCOPY

32.  For detection of purity
and consistency of
these trace metals
 Also for quantitative
determination of metals
mainly in solid sample
as mineral, ores and
alloys

33. •Magnesium in cast iron
• Silver, Zinc, Copper and Lead in Cadmium metal
• Determination Of Trace Copper In Nickel Metal

34.  Determination of trace metal in a silicon foam cavity wound dressing
Zinc in Zinc insulin suspension and tetracosactrin Zinc injection
 Copper and Iron in ascorbic acid
Aluminum in albumin solution and Ca, Mg,
Mercury
 Zinc in water used for diluting haemodialysis solution

35. •For the analysis of pharmaceutically or
therapeutically essential component of formulation,
such as Zinc in Zinc-insulin, minerals in
multivitamin-mineral preparation and Ca, Mg, Al in
antacids.
•To establish concentration limits where the metal is
regarded as an impurity.

36. •Mining industries
•Petroleum industries
•Determination of metallic elements in food
industry like Copper, Zinc and Nickel in vegetable
oil and copper in beer.

37.  Pharmaceutical Analysis: A Textbook for Pharmacy Students and
Pharmaceutical Chemists By David G. Watson
 Mass Spectrometry Principles & Applications By ED Hoffmann &
Stroobant.
 Mass Spectrometry By H-GROSS.
 Principles Of Instrumental Analysis By Holler & Skoog.
 Instrumental Techniques For Analytical Chemistry By FRAUT
SELLER.
 Organic Spectroscopy & Chromatography By M.YOUNAS

38.  Amirav, A.Gordin, A. Poliak, M. Alon, T. and Fialkov, A. B. (2008), "Gas
Chromatography Mass Spectrometry with Supersonic Molecular
Beams". Journal of Mass Spectrometry.
 Structural Identification Of Organic Compounds With Spectroscopic
Techniques By Richard R.Ernst .
 Introduction To Pharmaceutical Chemical Analysis By Steen Hansen.
 Mass Spectrometry By E.Constantin and A.Schnell.
www.Spectroscopy/Slideshare
www. Spectroscopy/Wiki

39.  Presented to:
Respected Sir Irshad & 3rd Prof (Eve)
 Presentation Given by Members of:
‘‘Real Pharmacist Group (RPG)’’
 Made By:
Faizan Akram (Faizy)
 Contributors:-
 Farhan Amin Zeeshan Khan
 Rashid Mumtaz Zeeshan Imtiaz
 Abdul Samad
 Abdul Muqeet