MASS SPECTROMETRY

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MASS SPECTROMETRY:

MASS SPECTROMETRY A.Solairajan, M.Pharm,1 st year, S.B.C.P. 3-Mar-12 Solairajan 1

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3-Mar-12 Solairajan 2 What is Mass Number? Zoo Zoo

Mass number:-:

Mass number:- The Mass number (A), also called atomic mass number or nucleon number is the total number of protons and neutrons in an atomic nucleus. 3-Mar-12 Solairajan 3

Example:-:

Example:- Carbon atom have 6 protons and 6 neutrons in the centre of the nucleus, 2 electrons situated in the inner orbital where as other 4 electrons are outside the orbital. We can represent carbon atom like 3-Mar-12 Solairajan 4 Mass Number(A) No.of protons(Z) Carbon Atom:-

Common elements and Mass number:

Common elements and Mass number 3-Mar-12 Solairajan 5

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Introduction Basic principles Instrumentation Ion formation & types Fragmentation process Fragmentation pattern 3-Mar-12 Solairajan 6

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Chemical ionisation MS (CIMS) Field ionisation MS (FIMS) Fast atom bombardment MS (FAB MS) Matrix assisted laser desorption/ ionisation MS (MALDI-MS) Gas chromatography MS (GC-MS) Interpretation of spectra Applications in pharmacy 3-Mar-12 Solairajan 7

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WHAT IS MASS SPECTROMETRY ? Mass spectrometry is an instrumental technique in which sample is converted to rapidly moving positive ions by electron bombardment and charged particles are separated according to their masses. WHAT IS MASS SPECTRUM ? Mass spectrum is a plot of relative abundance against the ratio of mass/charge(m/e). 3-Mar-12 Solairajan 8

Simple mass spectrometry:

Simple mass spectrometry 3-Mar-12 Solairajan 9

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Three principle behind mass spectra To measure relative molecular masses. To know the fragmentation of the molecules. Comparison of mass spectra with known compounds . 3-Mar-12 Solairajan 10

BASIC PRINCIPLES:

BASIC PRINCIPLES 3-Mar-12 Solairajan 11

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Loss of electron from a molecule leads to radical cation . 3-Mar-12 Solairajan 12 e- Molecular ion 15 eV 70 eV

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Electron removed from molecule orbital having lowest ionization potential (IP). In general n < π < σ 1 eV = 23 Kcal/mol 3-Mar-12 Solairajan 13 Compounds Ionization potential CH 4 12.6 eV C 2 H 4 10.52 eV CH 3 NH 2 10.3 eV

Components of mass spectrometer:

Components of mass spectrometer Inlet system Ion source Ionisation methods Mass Analysers Ion Detectors Vacuum System 3-Mar-12 Solairajan 14

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3-Mar-12 Solairajan 15

INSTRUMENTATION:

INSTRUMENTATION 3-Mar-12 Solairajan 16

Inlet System:

Inlet System SOLIDS SAMPLES with lower vapour pressure directly inserted into the ionization chamber and volatilization is controlled by heating the probe . LIQUIDS are handled by hypodermic needles injection through a silicon rubber dam . GASES SAMPLES are leaked into the ionisation chamber directly by the help of mercury manometer. 3-Mar-12 Solairajan 17 Inlet system

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The ion source is the part of the mass spectrometer that ionizes the material under analysis (the analyte ). The ions are then transported by magnetic or electric fields to the mass analyzer. Molecular ions are formed when energy of the electron beam reaches to 10-15 eV . Fragmentation of the ion reaches only at higher bombardment energies at 70 eV . 3-Mar-12 Solairajan 18 Ion sources:- Ionisation

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Ionisation Method Divided Into Two Categories . Gas phase ionisation (gases and vapour ) S amples are ionised outside the ion source. T his technique include, 1.Electron impact ionization (EIS) 2.Chemical ionization.(CI) 3.Field ionisation .(FI) Desorption technique (liquid ans solid) S amples are ionised inside the ion source. T his technique include, 1. Field desorption.(FD) 2. Fast atom bombardment.(FAB) 3. Laser desorption .(LD) 3-Mar-12 Solairajan 19 Ionisation

Ionizing agent in MS:

Ionizing agent in MS 3-Mar-12 Solairajan 20 Ionisation

IONIZATION METHOD IN MS:

IONIZATION METHOD IN MS 3-Mar-12 Solairajan 21 IONISATION METHOD COMPOUNDS MASS RANGE Electron impact ionisation Thermally volatile and stable 500 Da Chemical ionisation Thermally volatile and Stable 500 Da Electro spray ionisation Polar and Basic 70000 Da Fast atom bombardment Peptides 7000 Da Field ionisation Thermally volatile 1000 Da MALDI Large Biomolecules 3,00,000 Da Plasma desorption Neutral compounds 500 Da APCI Thermally liable 1000 Da SIMS Same as FAB 300-13000 Da Laser desorption Elemental analysis 500 Da

Electron impact ionisation:-:

Electron impact ionisation :- A beam of electrons passes through a gas-phase sample and collides with neutral analyte molecules (M) to produce a positively charged ion or a fragment ion. Generally electrons with energies of 70 eV are used to form a fragment ions. The positive ions are collected in focusing plates and passed to mass analyzer. 3-Mar-12 Solairajan 22 Ionisation

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3-Mar-12 Solairajan 23 Ionisation

Electrospray ionisation:-:

Electrospray ionisation :- The ESI source consists of a very fine needle and a series of skimmers. A sample solution is sprayed into the source chamber to form droplets. When droplets carry charge exit the capillary end, as the solvent evaporates, the droplets disappear leaving highly charged analyte molecules. 3-Mar-12 Solairajan 24 Ionisation

Chemical ionisation:-:

Chemical ionisation :- Chemical Impact Ionisation between interactions of sample with large amount of reagent gas. Commonly used reagent gases include methane,ammonia,isobutane . Oxygen and hydrogens are used in Negative ion chemical ionisation in MS. 3-Mar-12 Solairajan 25 Ionisation

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The vaporised sample is introduced into the mass spectrometer with an excess of a reagent gas (methane) at pressure of about 1 torr . The excess carrier gas is ionized by electron impact to the primary ions CH 4 .+ and CH 3 + . These may react with the excess methane to give secondary ions. 3-Mar-12 Solairajan 26 CI contd … Ionisation

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In this method the molecule pass through sharp metal anode carrying an electric field of 10 10 v m -1 Electrons are analysed in primary focusing cathode slit. ADV :- abundance of molecular ions. DISADV :- lower resolution. 3-Mar-12 Solairajan 27 Field ionisation :- Ionisation

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Useful for nonvolatile and thermolabile compounds. Sample is applied to field ion emitter and the solvent allowed to evaporate. Evaporated sample that leads to chemical ionisation or EIS. Example:- Nucleotides & Quarternary ammonium compounds . 3-Mar-12 Solairajan 28 Field desorption:- Ionisation

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Argon gas ionised by hot filament and focused beam that bombards the sample . Beam impinges the sample, a series of molecular reactions occur and analyse in MS analyser . Ex:- Insulin,Amino glycosides,Phospholipids . 3-Mar-12 Solairajan 29 Fast atom bombardment:- Ionisation

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Sample is coated with a high energetic fragment Californium 252. This fission fragment desorbs positive,negative , and neutral molecules. 252 cf generates 10 12 power at 10,000k, this may ionise the target molecule. This method involves the interaction of laser beam with sample to produce both vaporisation and ionisation . The vaporised sample passed to mass spectrometers for analysis. Appl :-used for elemental analysis . 3-Mar-12 Solairajan 30 Plasma desorption:- Laser desorption:- Ionisation

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MALDI is a LIMS method of vaporizing and ionizing and sample molecules are dispersed in a solid matrix such as nicotinic acid. A UV laser pulse ablates the matrix which carries some of the large molecules into the gas phase in an ionized form so they can be extracted into a mass spectrometer. 3-Mar-12 Solairajan 31 MALDI MALDI:- Ionisation

:

Atmospheric pressure chemical ionisation (APCI) is an analogous ionisation method to  chemical ionisation (CI). Corona discharge is used to ionize the analyte in the atmospheric pressure region. 3-Mar-12 Solairajan 32 APCI APCI:- Ionisation

SIMS:- :

SIMS:- Secondary ion mass spectrometry (SIMS) is based on the observation that charged particles (Secondary Ions) are ejected from a sample surface when bombarded by a primary beam of heavy particles. Primary beam species useful in SIMS include Cs+, O2+, O , Ar +, and Ga + 3-Mar-12 Solairajan 33 Ionisation

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An ion, after leaving ion source, the ions are separated according to their m/e ratio. In this area, the ions are accelerated by both electrostatic and magnetically Types:- Magnetic sector mass analysers Double focussing analysers Quadrupole mass analysers Time of Flight analysers (TOF) Ion trap analyser Ion cyclotron analyser 3-Mar-12 Solairajan 34 MASS ANALYSERS Mass Analyzer

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m/z= H 2 r 2 /2V H Magnetic field R Radius of the curvature V Applied voltage 3-Mar-12 Solairajan 35 Magnetic sector mass analyser :- Mass Analyzer

DOUBLE FOCUSSING ANALYSERS:

DOUBLE FOCUSSING ANALYSERS It contains two analysers namely Electrostatic analyser Magnetic sector analyser . 3-Mar-12 Solairajan 36 Mass Analyzer

QUADRUPOLE MASS ANALYSER:

QUADRUPOLE MASS ANALYSER The quadrupole consists of two pairs of parallel rods with applied DC and RF voltages. Ions are scanned by varying the DC/ Rf quadrupole voltages. 3-Mar-12 Solairajan 37 Mass Analyzer

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3-Mar-12 Solairajan 38 Mass Analyzer

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TOF analyzer – ions are accelerated through a flight tube and the time of light to the detector is measured. Typical flight times are 1 to 50 μ s. 3-Mar-12 Solairajan 39 TIME OF FLIGHT ANALYSER Mass Analyzer

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3-Mar-12 Solairajan 40

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The quadrupole ion trap typically consists of a ring electrode and two hyperbolic end cap electrodes. As the radio frequency voltage is increased, the orbits of heavier ions become stabilised,and passed into the detector. 3-Mar-12 Solairajan 41 ION TRAP ANALYSER Mass Analyzer

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Ions moving at their cyclotron frequency can absorb RF energy at this same frequency. A pulse of RF excites the ions in the magnetic field. The ions re-emit the radiation, which is picked up by the receiver plates. The decay produces a free-induction decay signal that can be Fourier transformed to produce the emitted frequencies, and therefore the masses of the ions present. 3-Mar-12 Solairajan 42 ION CYCLOTRON ANALYSER:- Mass Analyzer

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3-Mar-12 Solairajan 43

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Faraday cup Electron Multiplier photomultiplier Micro Channel Plate 3-Mar-12 Solairajan 44 DETECTORS:- Detector

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The basic principle is that the incident ion strikes the dynode surface which emits electrons and induces a current which is amplified and recorded. The dynode electrode is made of  a secondary emitting material like CsSb , GaP or BeO . It is ideally suited to isotope analysis and IRMS. 3-Mar-12 Solairajan 45 faradaycup Faradaycup :- Detector

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Electron multipliers are the most common especially when positive and negative ions need to be detected on the same instrument. Dynodes made up of copper-beryllium which transduces the initial ion current ,and electron emitted by first dynode are focused magnetically from dynode to the next. Final cascade current is amplified more than million times . 3-Mar-12 Solairajan 46 Electron Multipliers Detector

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The dynode consists of a substance( a scintillator ) which emits photons(light). The emitted light is detected by photo multiplier tube and is converted into electric current. These detectors are useful in studies on metastable ions 3-Mar-12 Solairajan 47 Photomultipliers:- Detector

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3-Mar-12 Solairajan 48 Micro channel Plate:- Detector

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All mass spectrometers need a vacuum to allow ions to reach the detector without colliding with other gaseous molecules or atoms. If such collisions did occur, the instrument would suffer from reduced resolution and sensitivity. 3-Mar-12 Solairajan 49 Vacuum system:-

FRAGMENTATION:

FRAGMENTATION Fragmentation is a type of chemical dissociation. Fragmentation takes place by a process of heterolysis or homolysis . Types of Fragmentation:- Collision induced dissociation(CID) Electron capture dissociation(ECD) Electron transfer dissociation(ETD) Electron detachment dissociation(EDD) Photo dissociation Infrared multiphoton dissociation(IRMPD) Blackbody infrared radiative dissociation(BIRD) Surface induced dissociation(SID) Charge remote fragmentation Higher energy C-trap dissociation(HCD) 3-Mar-12 Solairajan 50

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Collision Induced Dissociation Molecular ions are accelerated by electrical potential to high kinetic energy and then allowed to collide with neutral molecules like He,N or Ar . Collision between these molecules leads to bond breakage and formation of fragment ions. These fragment ions are analysed by mass spectrometer. Example:- Triple quadrupole spectrometer produces CID fragments. 3-Mar-12 Solairajan 51

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3-Mar-12 Solairajan 52 SORI-CID: -(Sustained Off-Resonance Irradiation Collision-Induced Dissociation ) It is one of CID technique used in Fourier transform ion cyclotron resonance mass spectrometry. In this method accelerating ions in cyclotron motion and increasing the pressure resulting collisions produce CID fragments.

Electron Capture Dissociation:-:

Electron Capture Dissociation:- It is a method of fragmenting gas phase ions for tandem mass spectrometric analysis (structural elucidation). ECD involves the direct introduction of low energy electrons to trapped gas phase ions. Electron-capture dissociation typically involves a multiply protonated molecule M interacting with a free electron to form an odd-electron ion. 3-Mar-12 Solairajan 53

Electron Transfer Dissociation:-:

Electron Transfer Dissociation :- ETD induces fragmentation of cations by transferring electrons to them . Example:-peptides or proteins . Electron Detachment Dissociation:- EDD is a method for fragmenting anionic species in mass spectrometry. 3-Mar-12 Solairajan 54

Photo Dissociation:-:

Photo Dissociation:- Photodissociation is a chemical reaction in which a chemical compound is broken down by photons . IRMPD:- Absorption of multiple infra red photons by a molecule and leads to dissociation. BIRD:- Long interaction of molecule with radiation field like carbon dioxide laser . Surface-induced dissociation:-(SID) It is a technique used in mass spectrometry to fragment molecular ions in the gas phase by collision of an ion with a surface under high vacuum . 3-Mar-12 Solairajan 55

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Charge Remote Fragmentation:- It is a type of covalent bond breaking that occurs in a gas phase ion in which the cleaved bond is not adjacent to the location of the charge. This fragmentation can be observed using tandem mass spectrometry . Higher-energy C-trap dissociation:- (HCD) It is a fragmentation technique, used for peptide modification analysis. Immonium ions generated via HCD pinpoint modifications such as phospho tyrosine. An added octopole collision cell facilitates de novo sequencing. 3-Mar-12 Solairajan 56

TYPES OF PEAKS IN MS:

TYPES OF PEAKS IN MS Molecular ion peak Fragment ions peak Rearrangement ions peak Metastable ion peaks Multicharged ions Base peak Negative ion peak Molecular ion Peak:- When a sample is bombarded with electrons of 9 to 15 eV energy, the molecular ion is produced, by loss of single electron. M e - M + + 2 e - 3-Mar-12 Solairajan 57

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Fragment ions Peak:- when an energy is given further more upto 70 eV , fragment ions produced, it have lower mass number. Rearrangement ion Peak:- Recombination of fragment ion is known as Rearrangement Peaks. Metastable ion Peak:- The ions resulting from the decomposition between the source region and magnetic analyser are called as Meta stable ions.These appear as broad peaks called Metastable ion Peaks. Multicharged ions:- Ions may exist with 2 or 3 charges instead of usual single charge.The peaks due to these charged ions are known as Multicharged ion peaks. 3-Mar-12 Solairajan 58

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Base Peak:- The largest peak in the mass spectrum corresponding to the most abundant ion or most intense peak in the spectrum is called as Base Peak. Negative ion Peak:- Negative ions are formed from electron bombardment of sample. These results due to the capture of electron by a molecule during collision of molecules . 3-Mar-12 Solairajan 59 Fragment ion peak

Fragmentation of the Molecular ion:

Fragmentation of the Molecular ion Fragmentation of a molecular ion, M, produces a radical and a cation . -Only the cation is detected by MS. 3-Mar-12 Solairajan 60

Description of Fragmentation process:- :

Description of Fragmentation process:- Fragmentation of the odd electron molecular ion (M .+ ) may occur by Homolytic or Heterolytic cleavage of a single bond. 3-Mar-12 Solairajan 61

Fragmentation rules:- (9 rules):

Fragmentation rules:- (9 rules) Rule:-1 The height of the M .+ peak decreases with increasing degree of branching. 3-Mar-12 Solairajan 62

Rule:-2 :

Rule:-2 The height of the M .+ Peak decreases with increasing molecular weight. Example:- Fatty molecules, steroids. 3-Mar-12 Solairajan 63

Rule:-3:

Rule:-3 The cleavage is favored at alkyl substituted carbons leads to formation of a carbocation . 3-Mar-12 Solairajan 64

Rule:-4:

Rule:-4 Double bonds, cyclic structures and aromatic rings stabilize M .+ and increase the probability of its appearance. 3-Mar-12 Solairajan 65 Molecular ion peak & Base peak

Rule:-5:

Rule:-5 Double bonds favor allylic cleavage to give the resonance stabilized cation. 3-Mar-12 Solairajan 66

Rule:-6:

Rule:-6 Saturated rings tend to lose alkyl side chains at the α bond (see rule 3) Unsaturated rings can undergo a Retro-Diels-Alder reaction 3-Mar-12 Solairajan 67

Rule:-7:

Rule:-7 Alkyl substituted aromatic compounds are cleaved preferably at the β bond to the ring, giving the resonance stabilized benzyl ion (or) tropyllium ion. 3-Mar-12 Solairajan 68

Rule:-8:

Rule:-8 C-C bonds next to hetero atom are frequently cleaved, leaving the charge on the hetero atom (resonance stabilization). 3-Mar-12 Solairajan 69

Rule:-9:

Rule:-9 Cleavage is often associated with elimination of small stable, neutral molecules, such as CO,olefins,water,ammonia,H 2 S,HCN,ketene or alcohols (often with rearrangements) Ex:- Mclafferty rearrangement 3-Mar-12 Solairajan 70

Mclafferty Rearrangement:-:

Mclafferty Rearrangement:- Mclafferty arrangement can occur in ketones,aldehydes,carboxylic acids, and esters . In this rearrangement a radical center in molecular ion derived from a lone pair or pi bond, removes hydrogen from the Gamma position( γ ) , a pi bond is formed between the β and γ position, and the bond between the α and β positions is broken. 3-Mar-12 Solairajan 71

α cleavage:

α cleavage 3-Mar-12 Solairajan 72 Alpha cleavage results in a broken bond next to the neighboring atom ( α position), and not the bond directly attached to the radical site. It is an expected pathway for carbonyl compounds,ethers,halides,alcohols,and amines .

Retro-Diels-Alder reactions:-:

Retro-Diels-Alder reactions:- Retro Diels-Alder fragmentation occurs in 3-cyano-cyclohexene, lets first look at the fragmentation of cyclohexene . First ionization occurs and electrons from the double bond transfer to an adjacent carbon and an electron from the bond between the 3 and 4 carbons transfers to form a second double bond that is conjugate with the first one. These rearrangements cleave the molecule between the 3 and 4 carbon and 5 and 6 (where another electron is transferred to form a double bond between the 4 and 5 carbons). This leaves an olefin and a diene . 3-Mar-12 Solairajan 73

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3-Mar-12 Solairajan 74 6 1 2 3 4 5 4 5 Diene Olefin

Nitrogen rule:-:

Nitrogen rule:- The nitrogen rule states, that a molecule that has no or even number of nitrogen atoms has an even nominal mass , whereas a molecule that has an odd number of nitrogen atoms has an odd nominal mass . 3-Mar-12 Solairajan 75 Example:-1 Example:-2

Contd….:

Contd …. The molecular ion appears at m/z 121, indicating an odd number of nitrogen atoms in the structure . 3-Mar-12 Solairajan 76 Odd number of molecular ion

IHD:-:

IHD:- In a hydrocarbon where all carbon atoms have only single bonds and no rings are involved, the compound would have maximum number of H atoms. If any of the bonds are replaced with double or triple bonds, there would be deficiency of H atoms. By calculating the index of hydrogen deficiency(IHD), we can calculate molecular formula and how many multiple bonds and rings are involved. IHD is also called the Degree of Unsaturation . A double bond and ring each counts as one IHD. A triple bond counts as two IHD . 3-Mar-12 Solairajan 77

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3-Mar-12 Solairajan 78 Example:-1 Example:-2 CH2=CH2

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3-Mar-12 Solairajan 79

Mass Spectrum of compounds:-:

Mass Spectrum of compounds:- Alkane :- 3-Mar-12 Solairajan 80 Base Peak Molecular ion peak

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Fragmentation of Cyclo Hexane:- C 6 H 12 + = 84 ( Molecular ion Peak ), C 4 H 8 + = 56 ( Base Peak ), (M-28) C 6 H 9 + = 69 (Fragment ion Peak), (M-15) C 3 H 7 + = 43 (Fragment ion Peak), (M-41) C 2 H 5 + = 29 (Daughter ion Peak), CH 3 + = 15 (Daughter ion Peak). 3-Mar-12 Solairajan 81

Alcohol:

Alcohol Possible Fragmentations are:- Mol.wt-46 C2H5OH+ =46 (Molecular ion peak) CH 3 O + = 31 (Base Peak) CHO + = 27 (Fragment ion Peak) CH 3 + = 15 (Daughter ion Peak) 3-Mar-12 Solairajan 82 Base Peak Molecular ion Peak Fragment ion Peak Daughter ion Peak

Aldehyde:-:

Molecular formula:-C 6 H 12 O Molecular Weight:-100 C 6 H 12 O + = 99 (Molecular ion Peak) C 3 H 8 + = 44 (Base Peak) C 4 H 9 + = 57 (Fragment ion Peak) C 2 H 5 + = 29 (Fragment ion Peak) 3-Mar-12 Solairajan 83 Aldehyde :- Fragment ion Peak Base Peak- Mclafferty rearrangement Molecular ion Peak- α cleavage

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3-Mar-12 Solairajan 84

Amide:-:

Amide:- Molecular wt :- 87, Molecular formula :- C 4 H 9 NO C 4 H 9 NO + = 87 (Molecular ion Peak), C 2 H 5 NO + = 59 (Base Peak) C = 44 (Fragment ion Peak) 3-Mar-12 Solairajan 85 Fragment ion Peak- α , β cleavage Base Peak- Mclafferty rearrangement Molecular ion Peak- β cleavage

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3-Mar-12 Solairajan 86

Amine:-:

Amine:- Molecular wt:-59 Mol.formula :-C 3 H 9 N 3-Mar-12 Solairajan 87 Molecular ion Peak- β -H transfer Base Peak- β -H transfer

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3-Mar-12 Solairajan 88

Ester:

Ester Mol.wt :-102, Mol.formula :-C 5 H 10 O 2 3-Mar-12 Solairajan 89 Base Peak- α cleavage Molecular ion Peak α -cleavage

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3-Mar-12 Solairajan 90

Ether:

Ether Mol.wt :-130 Mol.formula :-C 8 H 18 O 3-Mar-12 Solairajan 91 Base Peak-ipso cleavage α cleavage Molecular ion Peak- α cleavage

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3-Mar-12 Solairajan 92

Halide:

Halide Molecular wt:-106, Molecular formula:-C 4 H 7 O Cl 3-Mar-12 Solairajan 93 Base Peak- α cleavage α cleavage Mclafferty rearrangement Molecular ion Peak- α cleavage

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3-Mar-12 Solairajan 94

Ketone:

Ketone Molecular Wt:-86, Molecular formula:-C 5 H 10 O 3-Mar-12 Solairajan 95 Base Peak- α cleavage Molecular ion Peak- α cleavage Beta cleavage Mclafferty Rearrangement

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3-Mar-12 Solairajan 96

GC-MS:

GC-MS Gas chromatography–mass spectrometry ( GC-MS ) is a method that combines the features of gas-liquid chromatography and mass spectrometry to identify different substances within a test sample. Applications of GC-MS include :- Drug detection, Fire investigation, Environmental analysis, Explosives investigation, and Identification of unknown samples. 3-Mar-12 Solairajan 97

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3-Mar-12 Solairajan 98

Tandem MS:-:

Tandem MS:- What is Tandem MS :- - Uses 2 (or more) mass analyzers in a single instrument. -One purifies the analyte ion from a mixture using a magnetic field. -The other analyzes fragments of the analyte ion for identification and quantification . 3-Mar-12 Solairajan 99

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3-Mar-12 Solairajan 100

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Tandem mass spectrometry , also known as MS/MS or MS 2 , involves multiple steps of mass spectrometry selection, with some form of fragmentation occurring in between the stages. 3-Mar-12 Solairajan 101

Components of Tandem Mass Spectrometer:

Components of Tandem Mass Spectrometer 3-Mar-12 Solairajan 102 MS-1 Collision cell MS-2

Applications of Tandem MS:

Applications of Tandem MS Biotechnology & Pharmaceutical To determine chemical structure of drugs and drug metabolites. Detection/quantification of impurities, drugs and their metabolites in biological fluids and tissues . Analysis of liquid mixtures Fingerprinting Nutraceuticals /herbal drugs/tracing source of natural products or drugs Clinical testing & Toxicology Inborn errors of metabolism, cancer, diabetes, various poisons, drugs of abuse, etc. 3-Mar-12 Solairajan 103

MALDI-MS:

MALDI-MS Matrix-assisted laser desorption/ionization (MALDI) is a soft ionization technique used in mass spectrometry allowing the analysis of biomolecules (biopolymers such as DNA, proteins, peptides and sugars) and large organic molecules (such as polymers, dendrimers and other macromolecules ). 3-Mar-12 Solairajan 104

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3-Mar-12 Solairajan 105

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3-Mar-12 Solairajan 106

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3-Mar-12 Solairajan 107 Matrix Assisted Laser Desorption/Ionization (MALDI) Method where a laser is used to generate ions of high molecular weight samples, such as proteins and polymers. Analyte is embedded in to crystal matrix The presence of an aromatic matrix causes the large molecules to ionize instead of decomposing.

Applications of MS:-:

Applications of MS:- 3-Mar-12 Solairajan 108

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3-Mar-12 Solairajan 109 ww2.chemistry.gatech.edu/class/4341-6371/ fahrni /set02.pdf

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3-Mar-12 Solairajan 110

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3-Mar-12 Solairajan 111

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3-Mar-12 Solairajan 112