The document provides information about a colorimeter. It begins with an introduction to colorimeters, noting they measure light intensity and were invented in 1870. It then describes the basic principle that colorimeters measure light absorbed by colored solutions according to Beer's and Lambert's laws. The document outlines the typical parts of a colorimeter like its electronics and sample compartment. It discusses preparing blank, standard, and test solutions and explains Beer's and Lambert's laws. The document concludes by covering common colorimeter applications in clinical labs and industries like using them to estimate biochemical compounds in various samples.

1. COLORIMETER
PAUL-EAGLE YUSHAU
RAMAT OKYERE
LAWRENCIA ARYEE
ANTONIO K.
FULEAMENU

2. PRESENTATION OUTLINE
INTODUCTION AND BRIEF HISTORY
PRINCIPLE
PARTS, COMPONENTS AND SCHEMATICS
CUVETTES AND TEST PROCEDURE
BEER-LAMBERT’S LAW
ADVANTAGES AND DISADVANTAGES
APPLICATION
CARE, USE AND MAINTENANCE
REFERENCES

3. INTRODUCTION
Colorimeter is instrument which is used in the measurement of
the luminous intensity of light.
Invented by Louis Jules Duboscq in 1870.

4. COLORIMETER
It is the most common analytical technique
used in biochemical estimation in clinical
laboratory
It involves the quantitative estimation of color
A substance to be estimated colometrically,
must be colored or capable of forming
chromogens (colored complexes) through the
addition of reagents.
The color of light is the function of its
wavelength

5. COLORIMETER PRINCIPLE
When a monochromatic light passes
through a coloured solution, some specific
wavelengths of light are absorbed which is
related to colour intensity.
The amount of light absorbed or
transmitted by a colour solution is in
accordance with two law i.e. Beer’s &
Lambert’s Law.

6. TYPES OF COLORIMETER
DENSITOMETER
TRISTIMULUS COLORIMETER
SPECTRORADIOMETER
SPECTROPHOTOMETER

7. PARTS OF A
COLORIMETER
(1) Wavelength selection,
(2) Printer button
(3) Concentration factor
adjustment,
(4) UV mode selector
(Deuterium lamp)
(5) Readout
(6) Sample compartment
(7) Zero control (100% T),
(8) Sensitivity switch

8. COMPONENTS OF A
COLORIMETER
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9. BASIC COLORIMETER SCHEMATIC
Electronics

10. SAMPLE HOLDER/ CUVETTE
•Cuvettes are rectangular cell , square cell or circular
one.
•Made up of optical glass for visible wavelength
(quartz or fused silica for UV).
•Optical path (length) of cuvette is always1cm.
•Capacity may be 3ml/2ml/1ml depending upon the
thickness of the wall of the cuvette.
•For accurate and precise reading cuvette must be
transparent, clean, devoid of any scratches and there
should be no bubble adhering to the inner surface of
the filled cuvette.

11. PREPARATION OF SOLUTION FOR
INVESTIGATIONS
In colorimetric estimation it is necessary to prepare 3
solutions
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BLANK(B)
STANDARD(S)
TEST(T)

12. BLANK
To eliminate the effect of light
absorption by the reagent used
Water BLANK
Reagent BLANK
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13. STANDARD
Solution of known concentration of the
substance
Known concentration
So concentration of
unknown can be
calculated
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14. TEST
Test solution is made by
treating a specific volume of
the test sample with reagents
As per
manufacturers
procedure
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15. Observed Color of
Compound
Color of Light
Absorbed
Approximate
Wavelength of Light
Absorbed
Green Red 700 nm
Blue-green Orange-red 600 nm
Violet Yellow 550 nm
Red-violet Yellow-green 530 nm
Red Green 500 nm
Orange Blue 450 nm
Yellow Violet 400 nm

16. APPLICATIONS OF
COLORIMETER
• Estimation of biochemical compounds in
blood, plasma, serum, CSF, urine, etc.:
 Glucose
Urea
Creatinine
Uric Acid
Bilirubin
Lipids
Total Proteins
Enzymes [e.g. ALT, AST, ALP]
Minerals [Calcium, Phosphorus etc.]

17. LAMBERT’S LAW
•When a ray of monochromatic light passes
through an absorbing medium its intensity
decreases exponentially as the length of the
light path through light absorbing material
increases
BEER’S LAW
•The concentration of a substance is directly
proportional to the amount of light absorbed
or inversely proportional to the logarithm of
the transmitted light
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18. 5/19/2017 8:46 PM
Beer’s law
Beer’s law

19. RELATIONSHIP BETWEEN
WAVELENGTH & COLOUR
Wavelength between 400nm to 700nm form the visible
spectrum of light
visible band of light in electromagnetic spectrum

20. COLORIMETER
Advantages
It is inexpensive .
Very well applicable for quantitative analysis of colored
compounds.
Easily carried and transportable.

21. COLORIMETER
Disadvantages
Cannot be used for colorless compounds.
 It does not work in UV and IR regions.
We cannot set specific wavelength, as we have to set a range as a
parameter.
Similar colors from interfering substances can produce errors in
results .

22. APPLICATION
It is widely used in hospital & laboratory for estimation of
biochemical samples , like plasma, serum, cerebrospinal fluid (
csf ) , urine.
It is also used to quantitative estimation of serum components
as well as glucose, proteins and other various biochemical
compound.
They are used by the food industry and by manufacturers of
paints and textiles.

23. They are used to test for water quality, by screening for chemicals
such as chlorine, fluoride, cyanide, dissolved oxygen, iron,
molybdenum, zinc and hydrazine.
They are also used to determine the concentrations of plant nutrients
(such as phosphorus, nitrate and ammonia) in the soil or hemoglobin
in the blood and to identify substandard and counterfeit drugs.

24. USE, CARE AND MAINTENANCE OF
A COLORIMETER:
Read the user manual carefully.
Use the correct type of cuvette in the colorimeter as recommended by the manufacturer.
Make sure that the cuvette is clean and it’s optical surfaces are dry and free from finger marks
and scratches.
Clean the outside of the cuvette with tissue paper to remove any marks from the optical
surfaces.
To prolong the life of the lamp, switch off the colorimeter after use.
At the end of the day, disconnect It from the main switch and cover the colorimeter with its
protective cover.

25. Reference
 Instrumental method of chemical analysis,chatwal.
 Instrumental method of analysis, N.Grey, M.Calvin.
 Pharmaceutical analysis, Ashutoshkar.
 Instrumental method of analysis, B.K.Sharma
 Principles and application of ultaviolet and visible
spectroscopy, A.Rajasekaran.
 WWW.Pharmatwiter.com
 WIKIPEDIA

26. THANK YOU