Bombardment of molecules by an electron beam with energy
between 10-15ev usually results in the ionization of molecules by
removal of one electron (Molecular ion formation).
Introduction
working principle
fragmentation process
general rules for fragmentation
general modes of fragmentation
metastable ions
isotopic peaks
applications
Mass spectroscopy
1.Introduction
2. Principle
3. Theory
4. Instrumentation
5. Different types of Ionization
6. FAB
7. MALDI
8. APCI
9. ESI
10.Quardapole
introduction
Interference is a phenomena
that leads to changes (either positive or negative) in intensity of the analyte signal in spectroscopy.
Interferences in atomic absorption spectroscopy fall into two basic categories, namely, non-spectral and spectral.
1. spectral 2. Non Spectral ( Matrix interference, chemical interference, ionization interference)
PRINCIPLE - atomic absorpion spectroscopy
Atoms of the analyte have a fixed number of electrons.
If the light of a specific wavelength is passed through a flame containing that atom, electrons present in different energy levels, known as orbitals, absorb a certain wavelength and excite to higher energy levels.
The extent of absorption ά the number of ground-state atoms in the flame.
Only for information- The ground state is more stable than the excited state. The electrons spontaneously return back to the ground state. It emits the same amount of radiant energy. This process is called fluorescence. Fluorescence is used in atomic emission spectroscopy.
Brief note on - Instrumentation
The basic components of atomic absorption are:
Light source
Chopper
Atomizer
Burners
flames
Monochromators
Detectors
Amplifier
Readout devices
WORKING PROCESS
Calibration
Quantitative analysis in AAS
Safety measures
Important questions and answer
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
This ppt conains the history,introduction,theory and factors affecting fluorescence.This can me most helpful for the analysis students who were looking for the fluorescence topic with easily understandable way.
Introduction
working principle
fragmentation process
general rules for fragmentation
general modes of fragmentation
metastable ions
isotopic peaks
applications
Mass spectroscopy
1.Introduction
2. Principle
3. Theory
4. Instrumentation
5. Different types of Ionization
6. FAB
7. MALDI
8. APCI
9. ESI
10.Quardapole
introduction
Interference is a phenomena
that leads to changes (either positive or negative) in intensity of the analyte signal in spectroscopy.
Interferences in atomic absorption spectroscopy fall into two basic categories, namely, non-spectral and spectral.
1. spectral 2. Non Spectral ( Matrix interference, chemical interference, ionization interference)
PRINCIPLE - atomic absorpion spectroscopy
Atoms of the analyte have a fixed number of electrons.
If the light of a specific wavelength is passed through a flame containing that atom, electrons present in different energy levels, known as orbitals, absorb a certain wavelength and excite to higher energy levels.
The extent of absorption ά the number of ground-state atoms in the flame.
Only for information- The ground state is more stable than the excited state. The electrons spontaneously return back to the ground state. It emits the same amount of radiant energy. This process is called fluorescence. Fluorescence is used in atomic emission spectroscopy.
Brief note on - Instrumentation
The basic components of atomic absorption are:
Light source
Chopper
Atomizer
Burners
flames
Monochromators
Detectors
Amplifier
Readout devices
WORKING PROCESS
Calibration
Quantitative analysis in AAS
Safety measures
Important questions and answer
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
This ppt conains the history,introduction,theory and factors affecting fluorescence.This can me most helpful for the analysis students who were looking for the fluorescence topic with easily understandable way.
Quadrupole and Time of Flight Mass analysers.Gagangowda58
Description about important mass analysers Quadrupole and TOF: Principle, Construction and Working, Advantages and Disadvantages and their Applications.
TYPES OF PEAKS IN MASS SPECTROSCOPY.pptxAnupamaCp2
Types of peaks in mass spectroscopy.
Molecular ion or parent peak.
base peak.
fragment ions.
rearrangement ion.
multiple charged ion.
negative ion.
metastable ion.
isotopes ion.
MASS SPECTROSCOPY ( Molecular ion, Base peak, Isotopic abundance, Metastable ...Sachin Kale
CONTENT:
Molecular Ion Peak
Significance of Molecular ion & Graphically Method
Base Peak
Isotopic Abundance
Metastable Ion
Significance of Metastable ion
Nitrogen Rule & graphs
Formulation of Rule
In this slide contains Interference In Atomic Absorption Spectroscopy and applications.
Presented by: Shaik Gouse ul azam. ( department of pharmaceutical analysis.)
RIPER, anantpur.
Quadrupole and Time of Flight Mass analysers.Gagangowda58
Description about important mass analysers Quadrupole and TOF: Principle, Construction and Working, Advantages and Disadvantages and their Applications.
TYPES OF PEAKS IN MASS SPECTROSCOPY.pptxAnupamaCp2
Types of peaks in mass spectroscopy.
Molecular ion or parent peak.
base peak.
fragment ions.
rearrangement ion.
multiple charged ion.
negative ion.
metastable ion.
isotopes ion.
MASS SPECTROSCOPY ( Molecular ion, Base peak, Isotopic abundance, Metastable ...Sachin Kale
CONTENT:
Molecular Ion Peak
Significance of Molecular ion & Graphically Method
Base Peak
Isotopic Abundance
Metastable Ion
Significance of Metastable ion
Nitrogen Rule & graphs
Formulation of Rule
In this slide contains Interference In Atomic Absorption Spectroscopy and applications.
Presented by: Shaik Gouse ul azam. ( department of pharmaceutical analysis.)
RIPER, anantpur.
Ionization is the process by which an atom or a molecule acquires a negative or positive charge by gaining or losing electrons to form ions, often in conjunction with other chemical changes. Ionization can result from the loss of an electron after collisions with subatomic particles, collisions with other atoms, molecules and ions, or through the interaction with light. Heterolytic bond cleavage and heterolytic substitution reactions can result in the formation of ion pairs. Ionization can occur through radioactive decay by the internal conversion process, in which an excited nucleus transfers its energy to one of the inner-shell electrons causing it to be ejected.
Content:
Basic concepts
Fragmentation Process
McLafferty Rearrangement
Mass spectrum
Metastable ion
Isotopic peak
Nitrogen Rule
Basic Concept:
Mass spectrometry uses high energy electrons to break a molecule into fragmentation.
A beam of high-energy electrons breaks the molecule apart.
The masses of the fragments and their relative abundance reveal information about the structure of the molecule.
Separation and analysis of the fragments provides information about:
– Molecular weight
– Structure
Fragmentation Process
Bombardment of molecules by an electron beam with energy between 10-15ev usually results in the ionization of molecules by removal of one electron (Molecular ion formation)
When the energy of electron beam is increased between 50-70ev, these molecular ions acquire a high excitation resulting in their break down into various fragments. This process is called "Fragmentation process".
McLafferty Rearrangement:
Fragmentation due to rearrangement of Molecular or Parent ion:
The cleavage of bonds in Molecular ion is due to the intramolecular atomic rearrangement. This leads to fragmentation whose origin cannot be described by simple cleavage of bonds.
When fragments are accompanied by bond formation as well as bond for breaking, a rearrangement process is said to have occurred.
Such rearrangement involves the transfer of hydrogen from one part of the molecular ion to another via, preferably, a six-membered cyclic transition state.
This process is favoured energetically because as many bonds are formed as are broken.
Compounds containing hydrogen atom at position gamma to carbonyl group have been found to a relative intense peak.
This is probably due to rearrangement and fragmentation is accompanied by the loss of neutral molecule. This rearrangement is known as Mc Lafferty rearrangement.
Thus , the molecular formula of the unknown compound can be determined from the various fragment ions and also the parent ion of the mass spectrum .
More example of McLafferty reaarangements are :
A double McLafferty rearrangement is also reported in ketones .
The second hydrogen atom originates exclusively from the γ – position .
A secondary hydrogen is preffered to a primary hydrogen atom in this process . The mechanism involves.
Ketonisation of the intermediate enol ion by the hydrogen transfer .
Hydrogen transfer to enolic oxygen . Consider the McLafferty rearrangement in 4- Heptanone.
Mass Spectrum :
It is a record of the masses and the relative abundances of the molecular ion and the positively charged fragments formed from it by the electron bombardment.
The molecular ion or Parent ion :
The electron bombardment with energy 10-15 eV usually removes one electron from the molecule of the organic compoound in the vapour phase it results in the formation of molecular ion
The mass of the parent ion gives the molecular mass of the sample. .
in this presentation we learn about the mass spectrometery principal and its mass to charge ratio.
components of mass spectrometers .
sample inoculation and its processing. i feel these are very good slides.
Mass Spectrometry (MS) is an analytic technique used to determine the relative masses of molecular ions and fragments by calculating the degree of deflection of charged particles in a magnetic field.
It provides a great deal of information with very small amount of samples.
MS Fragmentation Process and Application of MS.pdfDr. Dinesh Mehta
Fragmentation process:
Bombardment of molecules by an electron beam with energy between 10-15ev usually results in the ionization of molecules by removal of one electron (Molecular ion formation).
Mass Spectrometry (MS) is an analytic technique used to determine
the relative masses of molecular ions and fragments by calculating the
degree of deflection of charged particles in a magnetic field.
It provides a great deal of information with very small amount of samples.
Unlike a spectrometer (which is any instrument that can measure the
properties of light over a range of wavelengths), a spectrophotometer
measures only the intensity of light as a function of its wavelength.
This presentation describes outlines and discusses the regulations
applicable to the QA function and unit, structure, function and
application of the unit in the pharmaceutical manufacturing
environment. In addition, it discusses additional quality – related
responsibilities that may result when manufactures move toward a
quality system approach to quality that incorporates current quality
system models to further improve quality and harmonize with inter-
national quality requirements.
ISO defines the audits as “systematic, independent and documented process for obtaining audit evidence and evaluating them objectively to determine the degree to which the verification criteria are met.”
Auditing Manufacturing Process and Product and Process Information.pdfDr. Dinesh Mehta
Manufacturing process audits should ensure that procedures are properly followed, problems are quickly corrected, there is consistency in the process, and there is continuous improvement and corrective action as needed.
CONTENTS
1. General areas interest in the building:
Walls and celling's
Floors and drains
Doors ,windows and fittings
Equipment
Pipelines
2. RAW MATERIALS
3. WATER
Microbiological results
Essential document
PQ is divided into 3 phases
Microbiological procedure reviewed
4. PACKAGING MATERIALS
A process audit is an examination of results to determine whether the activities, resources and behaviour that cause them are being managed efficiently and effectively.
A process audit is not simply following a trail through a department from input to output - this is a transaction audit.
As the audit proceeds, there might arise some situations where the facts indicate there is a failure, either partially or wholly, of the quality management system, such a situation is called nonconformity/ deficiencies”.
CHAPTER-1 Information Gathering and Administration.pdfDr. Dinesh Mehta
During the audit, information relevant to the objectives, scope and criteria, including information on interfaces between functions, activities and processes, should be collected by appropriate sampling and should be verified.
CHAPTER-1 Management Audit and Planning procedure.pdfDr. Dinesh Mehta
Audits are conducted to ascertain the validity and reliability of the information; also to provide an assessment of the internal control of a system. It provides management with information on the efficiency with which the company controls the quality of its processes and products
The versatile instrument is used to isolate unknown compounds from a HPTLC/TLC plate and transfer them into a mass spectrometer for identification or structure elucidation.
The aim of the coupling is to obtain an information-rich detection for both identification and quantification compared to that with a single analytical technique.
Benchmarking is defined as a technique in which an organisation compares its performance to that of 'best in class' organisations, discovers how other organisations achieve the levels they do, and uses that information to improve its own performance.
The hyphenated technique is a combination or coupling of two analytical techniques with the help of a proper interface.
The aim of the coupling is to obtain an information-rich detection for both identification and quantification compared to that with a single analytical technique.
Hyphenated techniques have received ever-increasing attention as the principal means to solve complex analytical problems.
Hyphenated techniques are widely used in chemistry and biochemistry and used for both quantitative and qualitative analysis of unknown compounds in complex natural product extracts or fraction and estimation of protein samples also.
Hyphenated technique is a combination or coupling of two analytical techniques with the help of proper interface.
In this presentation Hyphenated techniques-LC-MS/MS, GC-MS/MS, HPTLC-MS has been discussed
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Richard's entangled aventures in wonderlandRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
(May 29th, 2024) Advancements in Intravital Microscopy- Insights for Preclini...Scintica Instrumentation
Intravital microscopy (IVM) is a powerful tool utilized to study cellular behavior over time and space in vivo. Much of our understanding of cell biology has been accomplished using various in vitro and ex vivo methods; however, these studies do not necessarily reflect the natural dynamics of biological processes. Unlike traditional cell culture or fixed tissue imaging, IVM allows for the ultra-fast high-resolution imaging of cellular processes over time and space and were studied in its natural environment. Real-time visualization of biological processes in the context of an intact organism helps maintain physiological relevance and provide insights into the progression of disease, response to treatments or developmental processes.
In this webinar we give an overview of advanced applications of the IVM system in preclinical research. IVIM technology is a provider of all-in-one intravital microscopy systems and solutions optimized for in vivo imaging of live animal models at sub-micron resolution. The system’s unique features and user-friendly software enables researchers to probe fast dynamic biological processes such as immune cell tracking, cell-cell interaction as well as vascularization and tumor metastasis with exceptional detail. This webinar will also give an overview of IVM being utilized in drug development, offering a view into the intricate interaction between drugs/nanoparticles and tissues in vivo and allows for the evaluation of therapeutic intervention in a variety of tissues and organs. This interdisciplinary collaboration continues to drive the advancements of novel therapeutic strategies.
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
Ultraviolet-visible spectroscopy is an analytical method that can measure the amount of light received by the analyte.
THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.Sérgio Sacani
The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
2. Fragmentation process:
Bombardment of molecules by an electron beam with energy
between 10-15ev usually results in the ionization of molecules by
removal of one electron (Molecular ion formation).
When the energy of electron beam is increased between 50-70ev, these
molecular ions acquire a high excitation resulting in their break down
into various fragments. This process is called ― Fragmentation
process which is divided as given below.
Rearrangement Reactions
Rearrangement reactions accompanied by transfer of atoms:
Scrambling: Fragmentation giving rise to stable carbocation:
In certain cases fragmentation takes place at bond, which gives stable
carbocation.
Example- Molecular ion from the alkyl benzene undergoes
fragmentation at the benzylic bond and final product is seven
membered cyclic ion known as Tropylium ion.
3. (McLafferty rearrangement ions)
Metastable Ions
Simple Cleavage
a) Homolytic Cleavage
b) Heterolytic Cleavage
c) Retro-Diel’s-Alder reaction
d) Hydrogen Transfer rearrangements
Metastable Ions:
Fragment of a parent ion will give rise to a new ion (daughter) plus
either a neutral molecule or a radical.
M1+
M2+
+ non charged particle
An intermediate situation is possible; M1+
may decompose to
M2+
while being accelerated. The resultant daughter ion M2+
will not
be recorded at either M1or M2, but at a position M* as a rather broad,
poorly focused peak. Such an ion is called a metastable ion.
Nature of Metastable Ions:
Metastable ions have lower kinetic energy than normal ions and
metastable peaks are smaller than the M1and M2 peaks and also
broader. These metastable ions arise from fragmentation that takes
4. place during the flight down through ion rather than in the ionization
chamber.
Significance of Metastable ions:
Metastable ions are useful in helping to establish fragments
routes.
Metastable ion peak can also be used to distinguish between
fragmentation Processes, which occur in few microseconds.
Molecular ions formed in the ionization chamber do one of the
following things:
1. Either they decompose completely and very rapidly in the ion source
and never reach the collector (as in case of highly branched molecular
ions with life times less than 10-5
seconds).
2. Or else they survive long enough to reach the collector and be
recorded there (life times longer than 10-5
).
Homolytic cleavage:
Here fragmentation is due to electron redistribution between bonds.
In hemolytic cleavage the electrons are equally transferred to both
atoms & it forms radical and cation.
5. Heterolytic Cleavage
Fragmentation by movement of two electrons:
In this type of cleavage both the electrons of the bond are taken
over by one of the atoms; the fragments are an even electron cation
and a radical with the positive charge residing on the alkyl group. It
is designated by a conventional arrow (↶ or ↷) to signify the
transfer of a pair of electrons in the direction of the charged site.
Retro Diels-Alder reaction:
Elimination by multiple σ bond rupture:
6. Cyclohexene is broken down to Diene and Dienophile. It can be
explained by one or two electron mechanism.
Applications
Mass Spectrometry as a technique can be coupled with other
techniques such as HPLC and GC.
As it is used in the identification of compounds it is used in all
areas of science.
Some of its uses are : Trace Gas Analysis, Pharmaceutical
Industry, Space Exploration, Forensic Toxicology,
Archaeological Dating.
Mass spectrometry is fast becoming an indispensable field for analyzing
biomolecules. Till the1970s, the only analytical techniques which
provided similar information were electrophoretic, chromatographic or
ultracentrifugation methods. The results were not absolute as they were
7. based on characteristics other than the molecular weight. Thus the only
possibility of knowing the exact molecular weight of a macromolecule
remained its calculation based on its chemical structure.