This document discusses the components and operation of a UV spectrophotometer. It describes the main components as the source, wavelength selector, sample container, detector, and readout. It provides details on common sources like deuterium arc lamps, tungsten lamps, and xenon arc lamps. It also discusses wavelength selector devices like monochromators and filters. The document outlines the applications of UV spectrophotometry in areas like detection of impurities, structure elucidation, and quantitative analysis. In under 3 sentences.
INSTRUMENTAL METHODS OF ANALYSIS, B.PHARM 7TH SEM. AND FOR BSC,MSC CHEMISTRY. This is Geeta prasad kashyap (Asst. Professor), SVITS, Bilaspur (C.G) 495001
INSTRUMENTAL METHODS OF ANALYSIS, B.PHARM 7TH SEM. AND FOR BSC,MSC CHEMISTRY. This is Geeta prasad kashyap (Asst. Professor), SVITS, Bilaspur (C.G) 495001
UV- Spectroscopy (Modern Pharmaceutical Analytical Techniques.pptxRAHUL PAL
he Principle of UV-Visible Spectroscopy is based on the absorption of ultraviolet light or visible light by chemical compounds, which results in the production of distinct spectra. Spectroscopy is based on the interaction between light and matter.
UV spectroscopy or UV–visible spectrophotometry refers to absorption spectroscopy or reflectance spectroscopy in part of the ultraviolet and the full, adjacent visible regions of the electromagnetic spectrum.
In this slide contains principle of IR spectroscopy and sampling techniques.
Presented by: R.Banuteja (Department of pharmaceutical analysis).
RIPER, anantpur.
It is instrumental analytical technique. it is one of the major type of chromatography technique. its basic principle is adsorption. it has many applications in various fields
UV Spectrophotometric Method Development and Validation for Quantitative Esti...Sagar Savale
U.V Spectrophotometric method have been widely employed in determination of individual components in a mixture or fixed dose combination. Our aim is to develop spectroscopic method for estimation of the paracetamol in ternary mixture by using U.V spectrophotometry.
UV- Spectroscopy (Modern Pharmaceutical Analytical Techniques.pptxRAHUL PAL
he Principle of UV-Visible Spectroscopy is based on the absorption of ultraviolet light or visible light by chemical compounds, which results in the production of distinct spectra. Spectroscopy is based on the interaction between light and matter.
UV spectroscopy or UV–visible spectrophotometry refers to absorption spectroscopy or reflectance spectroscopy in part of the ultraviolet and the full, adjacent visible regions of the electromagnetic spectrum.
In this slide contains principle of IR spectroscopy and sampling techniques.
Presented by: R.Banuteja (Department of pharmaceutical analysis).
RIPER, anantpur.
It is instrumental analytical technique. it is one of the major type of chromatography technique. its basic principle is adsorption. it has many applications in various fields
UV Spectrophotometric Method Development and Validation for Quantitative Esti...Sagar Savale
U.V Spectrophotometric method have been widely employed in determination of individual components in a mixture or fixed dose combination. Our aim is to develop spectroscopic method for estimation of the paracetamol in ternary mixture by using U.V spectrophotometry.
The detailed information of UV Visible Spectroscopy, it includes the information regarding electronic transitions, Electromagnetic radiations, Various shifts.
UV - Visible Spectroscopy detailed information is included .The Spectroscopy study provide the information and the absorbance as well the concentration of the drugs is studied.
UV SPECTROSCOPY AND INSTRUMENTATION .INSTRUMENTAL METHODS OF ANALYSIS, B.PHARM 7TH SEM. AND FOR BSC,MSC CHEMISTRY.
This is Geeta prasad kashyap (Asst. Professor), SVITS, Bilaspur (C.G) 495001
THIS IS THE BASICS OF UV VISIBLE SPECTROSCOPY.
By reading this slide one can easily understand about uv-visible spectroscopy.
this topic is for physics student,chemistry student,engineering graduate as well as pharmacy student
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A spectrophotometer is an apparatus for measuring the intensity of light in a part of the spectrum, especially as transmitted or emitted by particular substances. The instrumentation of the Spectrophotometer is described in this presentation.
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https://www.etran.rs/2024/en/home-english/
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2. What is spectrophotometer ?
- A device used for measuring transmittance and
absorbance of a sample as a function of wavelength of
E.M.R.
Components of spectrophotometer→
- Source
- Wavelength selector Device
- Sample Container
- Detector
- Read out
4. SOURCES
Characterstics of an ideal source-
- Gives constant intensity
- Have low noise
- Prolonged stability
Types of UV-Visible sources-
- Deuterium Arc Lamp
- Tungsten lamp
- Xenon Arc Lamp
5. DEUTERIUM ARC LAMP
- It is a low pressure gas discharge light source.
- Works on the principle of molecular emission.
- Wavelength range→ (190-420)nm
- Life time approx 2000hrs.
6. Advantages-
-Yields good intensity continuum
-Provides intensity in UV region and useful intensity in the visible
region
-Produce low noise
Disadvantages-
-Don’t have prolonged stability
7. -Works on the principle of black body radiation.
-It is a spatially and temporarily incoherent source
-Wavelength range – (350 – 3000) nm
-Lifetime approx 10000 hrs
TUNGSTEN LAMP
8. Advantages-
-Yields good intensity continuum.
-Provides intensity over a part of the UV region and over the entire
part of the visible region.
-Produce low noise.
Disadvantages-
-Have poor assembly which can cause mechanical damage
through impact or vibration.
-Evaporation and condensation of tungsten filament causes
blackening of glass surface.
9. -Generates light by passing current through a gas (Xe) under
very high pressure.
-Wavelength range – (200 – 1000) nm.
-Lifetime – (500 – 4000) hrs.
XENON ARC LAMP
10. Advantages–
-Yields good intensity continuum.
-Provides intensity over the entire UV and visible region.
-Ruggedness – good to very good.
Disadvantages–
-Audible noise – higher.
-Requirement of high voltage
for initiation.
-Generate significant heat and
need external cooling.
11. Tungsten lamp is a better source than deuterium and xenon arc
lamp because –
-Produce less noise
-It have less cost
-Greater lifetime
CONCLUSION
13. Monochromator
• Function – to produce a beam of monochromatic (single
wavelength) radiation that can be selected from a wide range
of wavelengths.
• Components –
- Entrance slit .
- Collimating device (to produce parallel light ).
- Dispersing device (grating , prism).
- A focusing lens or mirror .
- An exit slit .
14. - By rotating prism or
grating we can get
the light of desired
wavelength.
15. Comparison between prism
and grating –
- Dispersion given by prism is
angularly non linear and temprature
sensitive while the dispersion given
by grating is angularly linear and
temprature insensitive .
- Dispersion is high in grating as
compaired to prism .
16. FILTERS
Filters are of four types :-
a) Absorption filters
b) Cut-off filters
c) Interference filters
d) Interference Wedges
17. Absorption Filters –
• They are made up of coloured glass
or dye .
• Transmit only a specific band
of wavelength.
• They are inexpensive.
• Transmission is only about (10-20)%.
18. Cut-off filters-
• Transmission is about 100%.
• Used to achieve only a specific band
of wavelength.
• They are used in combination with
absorption filters to decrease the
bandwidth of the absorption filters.
20. • The thickness of the dielectric and reflectivity of the metallic
films are carefully selected because these factors control the
transmitted wavelength.
• The transmitted radiation will have very narrow bandwidth.
21. Interference wedges-
• A wedge of dielectric of different thickness can transmit a wide
range of wavelengths.
• By choosing the correct position on the wedges , variable
bandwidths of about 20 nm can isolated.
22. Comparison between interference filters and
absorption filters-
• The interference filters gives superior bandwidth over absorption
filters.
• Greater the bandwidth the lower the transmittance % through that
filter .
23. - Sample containers are generally made up of
plastic, quarts and glass.
• Plastic cuvette- used for fast spectroscopic
assays, where speed is more important than
high accuracy.
• Glass cuvette- used in the wavelength range
of visible light.
- transmission range 340-2000nm
• Quartz cuvettes- they are of two types-
→ UV quartz- most common material.
- transmission range 190-2500 nm
→ IR quartz- rarely used
- transmission range 190-3500 nm
- Smallest capacity holding- 70 microliter
- Largest capacity holding- 2.5ml or larger
SAMPLE CONTAINER
24. DETECTORS
→A detector converts a light signal into an electrical signal. Ideally, it
should give a linear response over a wide range with low noise and
high sensitivity. Spectrophotometers normally contain either a
photomultiplier tube detector or a photodiode detector.
Phototube: –
- Incident photon causes release of
an electron
– Photocurrent α Plight
– Not best for low-light scenarios
25. Photomultiplier :-
– Ejected photoelectron strikes dynode, secondary e- released
– Voltage accelerates e- to next dynode and so on
• big voltage divider
– Result is large charge packet hitting anode
26. Photodiodes and Photodiode arrays :–
Reverse biased junction
– Photons produce e-- hole pairs α current
– Current α Plight
• less sensitive
• Assembly of individual photodiodes on a Si chip
• Each diode can be addressed individually
27. Single beam spectrophotometer
• Low in cost.
• High energy throughput due to non splitting of source beam.
• Have high sensitivity.
• Instability due to lack of compensation for disturbance like
electronic circuit fluctuation, voltage fluctuation, mechanical
components instability or drift in energy of light sources.
28. Double beam spectrophotometer
• Dual-beam instruments contain more optical components which
reduces throughput and sensitivity.
• The more complex mechanical design of the dual-beam
spectrophotometer may result in poorer reliability.
• Instability factors due to lamp drift, stray light, voltage
fluctuations do not affect the measurement.
29. APPLICATION
1. Detection of Impurities- UV absorption spectroscopy is one of the
best methods for determination of impurities in organic molecules.
2. Structure elucidation of organic compounds- UV spectroscopy is
useful in the structure elucidation of organic molecules, the presence
or absence of unsaturation, the presence of hetero atoms.
3. Quantitative analysis- UV absorption spectroscopy can be used for
the quantitative determination of compounds that absorb UV
radiation.
4. Qualitative analysis- UV absorption spectroscopy can characterize
those types of compounds which absorbs UV radiation. Identification
is done by comparing the absorption spectrum with the spectra of
known compounds.
30. Detection of Impurities
UV absorption spectroscopy is one of the best methods for
determination of impurities in organic molecules. Additional peaks
can be observed due to impurities in the sample and it can be
compared with that of standard raw material. By also measuring the
absorbance at specific wavelength, the impurities can be detected.
Benzene appears as a common impurity in cyclohexane. Its
presence can be easily detected by its absorption at 255
nm.
31. ACKNOWLEDGEMENT
I wish to express my sincere gratitude to Mrs. Jyoti Panday for
providing me an opportunity to do my presentation work on “UV
Spectrophotometer”
I sincerely thank Mrs. Jyoti Panday for their guidance and
encouragement in carrying out this presentation work. I also wish to
express my gratitude to my class friends of BBAU, who rendered
their help during the period of my presentation work.
.
