This document discusses the applications of UV-visible spectroscopy. It can be used quantitatively to determine the concentration and amount of a drug in a sample solution and calculate its percentage purity using various methods like calibration curves, single standard method, and determination of absorptivity values. Qualitatively, UV-visible spectroscopy can be used to detect impurities, elucidate organic structures, study functional groups, examine polynuclear hydrocarbons, determine molecular weights, and act as a detector for HPLC. It provides a versatile analytical technique across many fields.
this ppt contain all basic information related to the mass spectrometry like introduction, principle of MS, type of ions, fragmentation processes eg. mcLafferty rearrangement, alpha clevage, sigma bond clevage, retro-diels-alder reaction
this ppt contain all basic information related to the mass spectrometry like introduction, principle of MS, type of ions, fragmentation processes eg. mcLafferty rearrangement, alpha clevage, sigma bond clevage, retro-diels-alder reaction
In molecular spectroscopy, a Jablonski diagram is a diagram that illustrates the electronic states of a molecule and the transitions between them. The states are arranged vertically by energy and grouped horizontally by spin multiplicity.
Introduction to Spectroscopy,
Introduction to UV, electronic transitions, terminology, chromophore, Auxochrome, Examples and Applications.
Introduction to IR, Fundamental vibrations, Types of Vibrations, Factors affecting the vibrational freaquencies, Group frequencies, examples and applications.
In molecular spectroscopy, a Jablonski diagram is a diagram that illustrates the electronic states of a molecule and the transitions between them. The states are arranged vertically by energy and grouped horizontally by spin multiplicity.
Introduction to Spectroscopy,
Introduction to UV, electronic transitions, terminology, chromophore, Auxochrome, Examples and Applications.
Introduction to IR, Fundamental vibrations, Types of Vibrations, Factors affecting the vibrational freaquencies, Group frequencies, examples and applications.
Epidemiology , diagnosis and treatment of Hypertension Toufiqur Rahman
Hypertension, Blood pressure, Systolic Hypertension, Diastolic Hypertension, Epidemiology, Classification of hypertention, Type of hypertension, aetiology of hypertension, Clinical features, complications of hypertension, ambulatory blood pressure monitoring, Resistant hypertension, anti hypertensives,
3. TO DETERMINE THE CONC & AMOUNT OF
DRUG IN THE SAMPLE SOLUTION AND THUS
PERCENTAGE PURITY
1. USING A1% 1cm VALUES,WHEN REFERENCE STD IS NOT
AVAILABLE.
%PURITY = OBSERVED ABSORBANCE/A VALUE * 100/CONC
2. A1% 1cm IS NOT AVAILABLE, BUT REFERENCE STD
AVAILABLE
3. SINGLE STD OR DIRECT COMPARISON METHOD
A1 =ec1t
A2=ec2t
c2=c1*A2/A1
7. 1. 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.
9. 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.
From the location of peaks and combination of peaks, it
can be concluded that whether the compound is saturated
or unsaturated, hetero atoms are present or not etc.
10. 3. Analytical application
Since UV/visible absorption bands are usually intense,
small quantities of an observing substance can be easily detected .
4. Stereo chemical studies
The absorption by a conjugated system is due to the π→π*
transition. In the conjugated system the conjugation is decreased
from preventing coplanarity, which affects the absorption
spectrum. The UV/visible, therefore, provides useful tool for
studying stereo chemical details in certain molecules.
11. 5. Chemical kinetics
Kinetics of reaction can also be studied using
UV spectroscopy. The UV radiation is passed
through the reaction cell and the absorbance
changes can be observed.
12. 6. Detection of Functional Groups
This technique is used to detect the presence or absence
of functional group in the compound
Absence of a band at particular wavelength regarded as
an evidence for absence of particular group
14. 7. Examination of Polynuclear Hydrocarbons
Benzene and Polynuclear hydrocarbons have characteristic
spectra in ultraviolet and visible region. Thus identification
of Polynuclear hydrocarbons can be made by comparison
with the spectra of known Polynuclear compounds.
( Polynuclear hydrocarbons are the Hydrocarbon molecule with two
or more closed rings; examples are naphthalene, C10H8, with two
benzene rings side by side, or diphenyl, (C6H5)2, with two bond-
connected benzene rings. Also known as polycyclic hydrocarbon. )
16. 8. Molecular weight determination
Molecular weights of compounds can be measured
spectrophotometrically by preparing the suitable derivatives of
these compounds.
For example, if we want to determine the molecular weight of
amine then it is converted in to amine picrate. Then known
concentration of amine picrate is dissolved in a litre
of solution and its optical density is measured at λmax 380 nm.
17. After this the concentration of the solution in gm moles per litre can be
calculated by using the follwing formula.
From BEER LAMBERT’s law, log Io/It = €ct
"c" can be calculated using above equation & the weight "w" of amine picrate
is known. From "c" and "w", molecular weight of amine picrate can be
calculated. And the molecular weight of amine can be calculated using
the molecular weight of amine picrate.
Molecular weight can be calculated by using molar absorptivity value,using
the equation:
€ = A*(molecular weight/10)
18. 9. As HPLC detector
A UV/Vis spectrophotometer may be used
as a detector for HPLC.
20. 1. QUALITY CONTROL
2. DETERMINATION OF LIGAND/METAL RATIO IN METALLIC
COMPLEXES.
3. STUCTURAL ELUCIDATION OF ORGANIC COMPOUNDS.
4. DETERMINATION OF Pka VALUES OF INDICATORS.
5. DETERMINATION OF MOLECULAR WEIGHT OF AMINES.
6. DETERMINATION OF ELEMENTS ,IONS OR FUNCTIONAL GROUPS.
7. DETERMINATION OF ORGANIC SUBSTANCES AND
PHARMACEUTICALS.
8. USEFUL IN SPECTROPHOTOMETRIC TITRATIONS.