The document discusses various techniques for sample handling and preparation in infrared spectroscopy. It describes the different methods used for sampling solids, liquids, and gases. For solids, the key techniques discussed are running solids in solution, forming solid films, the mull technique, and pressed pellet preparation using KBr. For liquids, cells made of materials like NaCl, KBr, and ThBr are used. Gas samples utilize larger cells of the same materials to compensate for lower molecule numbers. Proper sample preparation is necessary to obtain infrared spectra without interference from cell materials.
In this slide contains principle of IR spectroscopy and sampling techniques.
Presented by: R.Banuteja (Department of pharmaceutical analysis).
RIPER, anantpur.
Introduction
working principle
fragmentation process
general rules for fragmentation
general modes of fragmentation
metastable ions
isotopic peaks
applications
PRINCIPLES of FT-NMR & 13C NMR
Fourier Transform
FOURIER TRANSFORM NMR SPECTROSCOPY
THEORY OF FT-NMR
13C NMR SPECTROSCOPY
Principle
Why C13-NMR is required though we have H1-NMR?
CHARACTERISTIC FEATURES OF 13 C NMR
Chemical Shifts
NUCLEAR OVERHAUSER ENHANCEMENT
Short-Comings of 13C-NMR Spectra
In this slide contains principle of IR spectroscopy and sampling techniques.
Presented by: R.Banuteja (Department of pharmaceutical analysis).
RIPER, anantpur.
Introduction
working principle
fragmentation process
general rules for fragmentation
general modes of fragmentation
metastable ions
isotopic peaks
applications
PRINCIPLES of FT-NMR & 13C NMR
Fourier Transform
FOURIER TRANSFORM NMR SPECTROSCOPY
THEORY OF FT-NMR
13C NMR SPECTROSCOPY
Principle
Why C13-NMR is required though we have H1-NMR?
CHARACTERISTIC FEATURES OF 13 C NMR
Chemical Shifts
NUCLEAR OVERHAUSER ENHANCEMENT
Short-Comings of 13C-NMR Spectra
Types of crystals & Application of x raykajal pradhan
some basic information:-
A crystal lattice is a 3-D arrangement of unit cells.
Unit cell is the smallest unit of a crystal, By stacking identical unit cells, the entire lattice can be constructed
A crystal’s unit cell dimensions are defined by six numbers, the lengths of the 3 axes, a, b, and c, and the three interaxial angles, α, β and γ.
If a unit cell has the same type of atom at the corners of the unit cell but not also in the middle of the faces nor in the centre of the cell, it is called primitive and given by symbol P
7 types of crystal system details
14 bravis lattice
APPLICATION X-RAY CRYSTALLOGRAPHY
1. Structure of crystals
2. Polymer characterisation
3. State of anneal in metals
4. Particle size determination
a) Spot counting method
b) Broadening of diffraction lines
c) Low-angle scattering
5.Applications of diffraction methods to complexes
a) Determination of cis- trans isomerism
b) Determination of linkage isomerism
6.Miscellaneous applications
a substance can absorb any visible light or external radiation and then again emit it. this called fluorescence and the process of reduction in fluorescence intensity is called quenching. this presentation is all about quenching of fluorescence.
Types of crystals & Application of x raykajal pradhan
some basic information:-
A crystal lattice is a 3-D arrangement of unit cells.
Unit cell is the smallest unit of a crystal, By stacking identical unit cells, the entire lattice can be constructed
A crystal’s unit cell dimensions are defined by six numbers, the lengths of the 3 axes, a, b, and c, and the three interaxial angles, α, β and γ.
If a unit cell has the same type of atom at the corners of the unit cell but not also in the middle of the faces nor in the centre of the cell, it is called primitive and given by symbol P
7 types of crystal system details
14 bravis lattice
APPLICATION X-RAY CRYSTALLOGRAPHY
1. Structure of crystals
2. Polymer characterisation
3. State of anneal in metals
4. Particle size determination
a) Spot counting method
b) Broadening of diffraction lines
c) Low-angle scattering
5.Applications of diffraction methods to complexes
a) Determination of cis- trans isomerism
b) Determination of linkage isomerism
6.Miscellaneous applications
a substance can absorb any visible light or external radiation and then again emit it. this called fluorescence and the process of reduction in fluorescence intensity is called quenching. this presentation is all about quenching of fluorescence.
SAMPLING TECHNIQUES FOR THE IR ANALYSIS including Techniques for Transmission (Absorption) Measurements and Sampling Techniques as well as description of the Solid Samples including
1) mulling
2) pelleting
3) thin film deposition
it also describes the Thin film deposition method
Thin layer chromatography technique - easier, cheaper.
Handling is easy. Used as an identification test also purity test. It comprises of stationary and mobile phase. There are various types of chromatography technique. TLC consists of three steps - spotting, development, and visualization. The Rf value is used to quantify the movement of the materials along the plate. Rf is equal to the
distance traveled by the substance divided by the distance traveled by the solvent. Its value is
always between zero and one. A TLC analysis might be summarized something like, "Using a silica
gel plate and ethyl acetate as the development solvent, unknown mixture X showed three spots
having Rf's of 0.12, 0.25, and 0.87". CThere are three components in TLC:
(1) the TLC plate (stationary phase), the development solvent (mobile phase), and the sample to be
analyzed (solute). In our experiment the TLC plate consists of a thin plastic sheet covered with a
thin layer of silica gel.
This presentation contains all the topics related to column chromatography. That includes introduction, principle,apparatus, experimental aspects of column chromatography, application of column chromatography, advantage and disadvantage of column chromatography with reference.
By Dhanashree R. Kavhale M.Pharm. (Pharmaceutical Chemistry) Sem II.
Flash chromatograpy is the advanced form of column chromatography in which the pressure is aplied for faster elution..
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
New Drug Discovery and Development .....NEHA GUPTA
The "New Drug Discovery and Development" process involves the identification, design, testing, and manufacturing of novel pharmaceutical compounds with the aim of introducing new and improved treatments for various medical conditions. This comprehensive endeavor encompasses various stages, including target identification, preclinical studies, clinical trials, regulatory approval, and post-market surveillance. It involves multidisciplinary collaboration among scientists, researchers, clinicians, regulatory experts, and pharmaceutical companies to bring innovative therapies to market and address unmet medical needs.
These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
Knee anatomy and clinical tests 2024.pdfvimalpl1234
This includes all relevant anatomy and clinical tests compiled from standard textbooks, Campbell,netter etc..It is comprehensive and best suited for orthopaedicians and orthopaedic residents.
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
Acute scrotum is a general term referring to an emergency condition affecting the contents or the wall of the scrotum.
There are a number of conditions that present acutely, predominantly with pain and/or swelling
A careful and detailed history and examination, and in some cases, investigations allow differentiation between these diagnoses. A prompt diagnosis is essential as the patient may require urgent surgical intervention
Testicular torsion refers to twisting of the spermatic cord, causing ischaemia of the testicle.
Testicular torsion results from inadequate fixation of the testis to the tunica vaginalis producing ischemia from reduced arterial inflow and venous outflow obstruction.
The prevalence of testicular torsion in adult patients hospitalized with acute scrotal pain is approximately 25 to 50 percent
1. SAMPLING TECHNIQUES IN
INFRA RED SPECTROSCOPY
UNDER THE GUIDANCE OF
MR.M.M. ESWARUDU M.PHARM
ASST.PROFESSOR
DEPT OF PHARMACUTICALANALYSIS
VIGNAN PHARMACY COLLEGE
VADLAMUDI CHEBROLU
A.P 522213
SUBMITTED BY
P. JAGADEESH
15AB1R0054
VIGNAN PHARMACY COLLEGE, VADLAMUDI 1
2. Contents :
1. Introduction
2. IR Region
3. Principle
4. Sample Handling Techniques In IR
5. Sample Cell
6. Sampling Of Solids
7. Sampling Of Liquids
8. Sampling Of Gases
9. Instrumentation
10. Conclusion
VIGNAN PHARMACY COLLEGE, VADLAMUDI 2
3. INTRODUCTION
Spectroscopy :
Spectroscopy is the study of the interaction between matter and radiated
energy or radiation.
Infrared Spectroscopy : (IR spectroscopy) is the spectroscopy that
deals with the interaction of only infrared region of the electromagnetic
spectrum with the matter.
Spectroscopy : Qualitative
Spectrometry : Quantitative
Valuable tool for the detemination of organic, and to a lesser extent,
inorganic structure.
VIGNAN PHARMACY COLLEGE, VADLAMUDI 3
4. This region is divided into different sections:
Region Energy
(kj/mole)
Wave number
(cm-1 )
Wave
length(µm)
Near IR 150-50 12,800-4000 0.78-2.5
Mid IR 50-2.5 4000-200 2.5-50
Far IR 2.5-0.1 200-10 50-1000
IR REGION
IR spectroscopy refers broadly to that region of electromagnetic
spectrum which lies between visible and microwave regions.
VIGNAN PHARMACY COLLEGE, VADLAMUDI 4
5. Principle:
• A chemical substance shows marked selective absorption in IR region.
• After absorption of IR radiation the molecules of chemical substance
vibrate at many rates of vibration giving rise to closely packed
absorption spectrum called as IR absorption spectrum.
• Various bands present in the IR spectrum corresponds to characteristic
functional group and bonds present in the chemical substance.
• Thus IR spectrum of a chemical substance is fingerprint for its
identification.
VIGNAN PHARMACY COLLEGE, VADLAMUDI 5
6. SAMPLE HANDLING TECHNIQUES IN IR SPECTROSCOPY:
• Samples of different phases have to be treated differently.
• The only common point to the sampling of different phases is that the
material containing the sample must be transparent to IR radiation.
• This condition restricts our selection to only certain salts like NaCl or
KBr.
• However, a final choice of salt will depend on the wavelength range to
be studied.
• Miller (1965) developed appropriate methods to handle samples in the
gas, liquid and solid phase.
VIGNAN PHARMACY COLLEGE, VADLAMUDI 6
7. SAMPLE CELL:
• Sample handling presents a number of problems in IR region.
• There is rugged window material for cuvette that is transparent and
also inert over this region.
• The alkali halides are widely used, particularly NaCl, KBr and which
is transparent at wavelength as long as 625 cm -1.
• AgCl cells are used for aqueous and moist samples but it is soft and
easily gets deformed and darkens on exposure to visible light.
• Cells made up of Teflon and polyethylene can be used, but Teflon
shows bands due to C-C & C-F.
• For frequencies less than 600 cm-1, a polyethylene cell is used.
•Sample concentrations required is from 0.1-10%
VIGNAN PHARMACY COLLEGE, VADLAMUDI 7
8. Precautions:
• Cell windows are easily fogged by exposure to moisture and require
frequent polishing with buffer powder which returns them to their
original condition.
• Since alkali metal halides, with which cell is made up of are
hygroscopic so must be protected from moisture by working at a
suitable temperature.
VIGNAN PHARMACY COLLEGE, VADLAMUDI 8
9. SAMPLING OF SOLIDS:
Generally 4 techniques are employed for preparing solid samples:
1. Solids run in solution.
2. Solid Films.
3. Mull technique.
4. Pressed pellet technique.
VIGNAN PHARMACY COLLEGE, VADLAMUDI 9
10. SOLIDS RUN IN SOLUTION:
Solids may be dissolved in non-aqueous solvent.
No chemical interaction between solute and solvent and also solvent
not absorb in the studied range.
A drop of the solution is placed on an alkali metal disc and the solvent
allowed to evaporate, leaving a thin film of the solute or the entire
solution placed in liquid sample cell.
If the solution can be prepared in a suitable solvent then the solution is
run in one of cells for liquid.
But this method is not for all solids as suitable solvents are limited and
no single solvent is transparent through the IR region.
VIGNAN PHARMACY COLLEGE, VADLAMUDI 10
11. Solvents:
• Solvent must be dry and transparent in the region of interest.
• A common pair of solvents is CCl4 and CS2.
• CCl4 is relatively free of absorption at frequencies above 1333 cm-1
where as CS2 shows little absorption below 1333cm-1.
• Solvent and solute combinations that must be avoided.
• For example, CS2 cannot be used as a solvent for primary or
secondary amines. Amino alcohols react slowly with CS2 CCl4.
• To obtain the spectra of polar materials that are insoluble in CCl4 and
CS2, chloroform, methylene chloride, acetonitrile and acetone are
useful solvents.
VIGNAN PHARMACY COLLEGE, VADLAMUDI 11
12. Demerit:
• This method can’t be used for all solids because suitable solvents are
limited in number & there is no single solvent which is transparent
throughout IR region.
Precautions:
• Solute chemical interaction with the solvent must be taken into
consideration especially for compounds having property of H-bonding.
• The solvent should not absorb in the studied range.
VIGNAN PHARMACY COLLEGE, VADLAMUDI 12
13. SOLID FILMS:
• Use only when the material can be deposited from the solution or
cooled from a melt as micro crystals or as glassy film.
• Care must be taken to free the sample of solvent.
• Films of crystalline solid generally lead to excessive light scattering.
• This technique is used for qualitative analysis but not for quantitative
analysis
Evaporate solvent by gentle heating
Dissolve them in reasonable volatile solvent and solution is formed.
Polymers, resins and amorphous solids
VIGNAN PHARMACY COLLEGE, VADLAMUDI 13
14. MULL TECHNIQUE:
• In this technique a small quantity of sample is thoroughly ground in a
clean mortar until the powder is very fine.
• After grinding, the mulling agent (mineral oil or Nujol) is introduced in
small quantities just sufficient to take up the powder (mixture
approximates the consistency of a toothpaste).
• The mixture is then transferred to the mull plates & the plates are
squeezed together to adjust the thickness of the sample between IR
transmitting windows.
• This is then mounted in a path of IR beam and the spectrum is run.
VIGNAN PHARMACY COLLEGE, VADLAMUDI 14
17. Advantages of this technique over mull technique:
• The use of KBr eliminates the problem of bands which appear in IR
spectrum due to the mulling agent as in this case no such bands appear.
• KBr pellets can be stored for longer periods of time.
• As concentration of the sample can be suitably adjusted in pellets, it can
be used for quantitative analysis.
• The resolution of spectrum in KBr is superior to that obtained with
mulls.
• This method is good for qualitative analysis but not for quantitative
analysis.
VIGNAN PHARMACY COLLEGE, VADLAMUDI 17
18. Demerit:
• Although Nujol is transparent throughout IR region, yet it has a
disadvantage that it has absorption maxima at 2915, 1462, 1376 &719 cm-1.
• So when IR spectrum of solid sample is taken in Nujol mull, absorption
bands of solid sample that happen to coincide with the absorption bands of
the Nujol mull will be hidden and then interferes with the absorption of the
sample.
• This interference can be avoided by using Hexachlorobutadiene in
combination with nujol which absorbs in regions 1630-1510 cm -1, 1200-
1140 cm-1, 1010-760 cm-1 and thus permits the recording of IR spectra of
only the sample.
VIGNAN PHARMACY COLLEGE, VADLAMUDI 18
19. PRESSED PELLET TECHNIQUE:
• In this technique a small amount of finely ground solid sample is
intimately mixed with about 100 times its weight of powdered Potassium
bromide, in a vibrating ball mill.
• This finely ground mixture is then pressed under very high pressure
(25000 p sig) in evacuable die or minipress to form a small pellet (about 1-
2 mm thick and 1cm in diameter).
• The resulting pellet is transparent to IR radiation and is run as such.
VIGNAN PHARMACY COLLEGE, VADLAMUDI 19
22. Demerits:
• It always has a band at 3450 cm-1, from –OH group of moisture present
in the sample.
• The high pressure involved during the formation of pellets may bring
about polymorphic changes in crystallinity in the samples, (Especially
inorganic complexes) which may cause complications in IR spectrum. In
some cases, even substitution of the ligand by bromide may be possible in
inorganic complexes.
• This method is not successful for some polymers which are difficult to
grind with KBr.
VIGNAN PHARMACY COLLEGE, VADLAMUDI 22
23. SAMPLING OF LIQUIDS:
• Liquids at room temperature.
• Rectangular cells made of NaCl, KBr and ThBr.
• Sample thickness should be 0.01-0.05mm to give transmittance
between 15% and 70%.
• If a cell possesses good quality windows, flat and parallel, its thickness
,t , in cm can be calculated from the following equation.
• Where ,
N is the number of fringes
w1–w2 are wave numbers
2t = N/w1–w2
VIGNAN PHARMACY COLLEGE, VADLAMUDI 23
24. • For double beam work “matched cell” are generelly employed.
• One cell will contain the sample while the other will have solvent
used in the sample.
• Matched cells must have same thickness.
• All cells should be protected from moisture because they dissolve in
water.
• For similar reasons organic liquid samples must be dried before
pouring into cells.
VIGNAN PHARMACY COLLEGE, VADLAMUDI 24
26. SAMPLING OF GASES:
•The gas sample cell is similar to cell for liquid samples and made of
KBr, NaCl & so on.
• To compensate for the small number if molecules of a sample that is
contained in a gas, however, the cells are larger, usually they are about
10cm long, but they may be up to 1m long.
• Multiple reflections can be used to make effective path length as long
as 40cm, so that constituents of the can be determined.
•Gas must not react with the cell windows or the reflecting surfaces.
VIGNAN PHARMACY COLLEGE, VADLAMUDI 26
27. • Gas analysis are performed with IR but the method is not commonly
used because of its lack of sensitivity.
• Moisture can be avoided.
•It is strong absorption bands at 3701cm-1 and 1625cm-1 may interfere
in the analysis .
• IN addition, the windows and other instrument components which are
constructed of soluble salts may be damaged.
VIGNAN PHARMACY COLLEGE, VADLAMUDI 27
30. Source:
Infrared radiation is produced by electrically heating a source, usually
a Nernst filament or a Globar to 1000-1800°C.
The Nernst filament is fabricated from a binder and oxides of
thorium, cerium, zirconium and yttrium.
The Globar is a small rod of silicon carbide usually 5 cm in length
and 0.5 cm in diameter.
The maximum radiation for the Globar occurs in the 5500-5000cm-1
region.
Nichrome wire, carbon arc, rhodium wire and tungsten filament lamp
are also used as light source.
VIGNAN PHARMACY COLLEGE, VADLAMUDI 30
31. Monochromator:
A monochromator is a means of separating wavelengths of the source
radiation.
The monochromator is used to separate polychromatic radiation into
a suitable monochromatic form [105].
This is achieved by means of prisms or diffraction grating.
A monochromator thus carries out three functions:
1 • It disperses the radiation according to its wave number
components.
2
• It restricts the radiation falling on the detector into a narrow wave
number range.
3
• It maintains the energy incident on the detector to an
approximately constant level.
VIGNAN PHARMACY COLLEGE, VADLAMUDI 31
32. Detector:
Detectors used in infrared spectrophotometers usually convert the
thermal radiant energy into electrical energy, which can subsequently be
plotted on a chart recorder.
Two Types of the detectors are commonly used:
1. Thermal Detectors, in which the infrared radiation produces a heating
effect that alters some physical property of the detector.
2. Photon detectors, which use the quantum effects of the infrared
radiation to change the electrical properties of a semiconductor
VIGNAN PHARMACY COLLEGE, VADLAMUDI 32
33. Amplifiers and recorders :
The radiant energy received by the detector is converted into
measurable electrical signal and is amplified by the amplifiers.
The amplified signal is registered by a recorder or a plotter.
The recorder is driven with a speed which is synchronized with that of
a monochromator, so that, the pen moving across the chart, records the
transmittance of the sample as a function of the wavenumber.
VIGNAN PHARMACY COLLEGE, VADLAMUDI 33
34. REFERENCES:
1. Instrumental methods of chemical analysis, 5th edition,
Gurdeep.R.Chatwal & Sham.K.Anand, Pg.No.2.29.
2. Instrumental methods of analysis, 7th edition, Willard, Merritt, Dean
& Settle, Pg. no. 305-310.
3. Instrumental methods of chemical analysis, 26th edition,
B.K.Sharma, Pg.No.262-264.
4. Organic spectroscopy, third edition, William Kemp, pg. no. 51.
5. Elementary organic spectroscopy, Y. R. Sharma, pg. no. 91.
6. Spectrometric identification of organic compounds,
R. M. Silverstein& F.X. Webster, pg. no. 77.
7. www.redpoll.pharmacy.ualberta.ca/.../slideoo31.htm
VIGNAN PHARMACY COLLEGE, VADLAMUDI 34
37. ACKNOWLEDGEMENT
I would like to express my gratitude to all those who gave me
the possibility to complete this seminar.
I express my sincere gratitude to my guide M.M. Eswarudu,
who suggested with great patience.
A special thanks to the principal sir , Dr. P. Srinivasa Babu
garu and special thanks to Sowjanya madam and seminar
committee whose encouragement contributed immensely to
complete my seminar.
VIGNAN PHARMACY COLLEGE, VADLAMU
37