Who Needs Photons When You Who Needs Photons When You Have Mass?Have Mass?

Lecture 2. ACCA Spectroscopy SeriesLecture 2. ACCA Spectroscopy SeriesSept. 22, 2009 Sept. 22, 2009

Bruce Solka, Ph.D.Bruce Solka, Ph.D.Sr. Principal Scientist, Unilever, retired Sr. Principal Scientist, Unilever, retired

Mass Spectrometry:Mass Spectrometry:

● What is it?

● Why do it?

● How does one do it?

To be followed with some illustrations of practical applications

*

* a misnomer ? (light involved only in special cases)

mass

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The language of mass spectrometry as used in this talk.

DaltonAMUIonIsotopeSample inletIon sourceMass analyzerIon trapQuadrupoleMagnetic sectorTurbomolecularMolecular ionFragment ionIsotopeBase peak

Mean free pathElectron impactElectrosprayChemical IonizationTotal ion chromatogramMass chromatogramGC-MSHPLC-MSDesorption ElectrosprayCollision-induced dissociation

How to provide a tour of mass How to provide a tour of mass spectrometry ?spectrometry ?

1. Introduction1. What is MS2. Who am I to say3. What do they look like4. Who uses MS and why

2. How does MS work3. Details of some

applications Applications

An instrument that literally measures mass of molecules

ASMS poster “what is mass spec?

1.What is mass spec?1.What is mass spec?

Details…● Effects of electromagnetic fields on ions made from the molecule.● Mass of fragments of molecule also used.

●Then, the mass can be used as a tag to determine what molecules are present in a mixture and at what concentration.

• An instrument used to answer the questions of→ What is present?→ How much is there?

1. What is mass spec? (cont.)1. What is mass spec? (cont.)

Advantages over many other types of spectroscopy:

“What” can range from a hydrogen atom, H mass = 1 amu), to an A,B,C transporter protein of mass 400 kD (400000 amu).

“How much” can be measured in femtograms (10-15 g) attomoles (10-18 moles) and parts-per-trillion.

Extraordinarily versatile, specific, and sensitive

• Your Guide: Bruce Solka, Ph.D., retired– Energy (synfuels) at GTI and then to consumer products at Unilever– Postdocs in MS at U of Toronto & Purdue U– Ph.D (NIU)– Started in ca 1966…>40 years of mass spec Someday,

these will be the “good old

Days”

Who am I to say what Mass Spec is?Who am I to say what Mass Spec is?

Mass Spectrometry ca. 1968Mass Spectrometry ca. 1968Hitachi RMU-6 Magnetic Sector

Sample inlet

Ion formation“big” electromagnet

detector

To establish a sense of what we’ll be To establish a sense of what we’ll be talking about…talking about…

And because mass spectrometers come in a very wide And because mass spectrometers come in a very wide variety of sizes and types,variety of sizes and types,

Next several slides are images of various types of modern mass spectrometers

Basic GC-MS: Benchtop, < $50,000 (chemist not included)

to 1000 amu , most EPA work, flavors & fragrances, general organic

NCIS, CSI, etc

Gas chromatograph inlet

MassSpec

HPLC-MS @ $300,000Includes ESI, MALDI, APCI ionization

Ideal for proteomics studies (and most general non-volatile organic analyses).

Note: Compared to last slide, MS now bigger than sample inlet

Lawrence-Livermore Labs “Accelerator Mass Spectrometer” (1MV)

Isotope analysis…radiocarbon dating, geology, botany, etc.(one of 5 in U.S.)

http://www.physics.purdue.edu/primelab/

Sensitive to isotope abundances at 1 in 1 x 1015

10Be, 14C, 26Al, 36Cl, 41Ca, 129I

(Inside of shielded, super-con magnet}

Mass spec #2, FTMS, or ICR

Mass spec #1…LIT-MS to form and select ions for study in…

FTMS: Super-High resolution, mass range, and sensitivity, ($800000)

Used in:•Genomics•Proteomics•Syn. Polymers•General Organic

The Torion corp. “Guardion-7”…30 lbs and ready in 3 min.

llllllIII’ll find those #@*^@ pollutants

Or terrorist explosive caches, etc.

How to provide a tour of mass How to provide a tour of mass spectrometry ?spectrometry ?

1. Introduction1. What is MS2. Who am I to say3. What do they look like4. Who uses MS and why

2. How does MS work1. Mass analyzers2. Ion sources

3. Details of some applications Applications

2. Why do mass spec ?2. Why do mass spec ?• You will probably use mass spec if you’re • An anesthesiologist monitoring OR atmosphere OR atmosphere or patient breath gasesbreath gases• TSA Security checking passengers for explosive residuesexplosive residues.

• A biochemist determining physical location of a drug metabolite drug metabolite within a cell.• A Crime lab analyst identifying a greasy residuegreasy residue.• Geochemist determining the age of a petroleum age of a petroleum reservoir. • Archeologist identifying a resinresin in an artifact.• Art historian determining a pigmentpigment in authentication of a painting.• Chemist determining the cause of a malodormalodor in a consumer complaint.• Chemist determining why a blueblue shampoo has turned greenturned green.• Molecular biologist determining amino acid sequence amino acid sequence of a new protein.• USA PFC responsible for detecting presence of any nerve gas nerve gas on the battlefield.• Environmental analyst determining whether a cancer cluster may be due to carcinogens in the air, water, or soilcarcinogens in the air, water, or soil.

Mass spec, if practiced in all of it’s various modes is extremely versatile!!!

• • Is there really water on Mars?Is there really water on Mars?

Project Phoenix Mars Lander (2008)Project Phoenix Mars Lander (2008)

Sample ovens and ion source

Magnetic sector mass analyzer

Detector

How to provide a tour of mass How to provide a tour of mass spectrometry ?spectrometry ?

1. Introduction1. What is MS2. Who am I to say3. What do they look like4. Who uses MS and why

2. How does MS work1. Mass analyzers2. Ion sources

3. Details of some applications

1. Magnetic sector MS2. Quadrupole MS3. Ion trap MS

1. Quadrupole2. Linear

4. Time of Flight MS5. FTMS (Ion cyclotron

resonance)6. Orbitrap™7. Hybrids of above

2. How does it work?2. How does it work?

2.1. Mass Analyzers mass range?, mass resolution? Sensitivity?

ALL depend on mass-dependant interaction of ions ALL depend on mass-dependant interaction of ions with electromagnetic fields.with electromagnetic fields.

http://www.cem.msu.edu/~reusch/VirtualText/Spectrpy/MassSpec/masspec1.htm

eV = ½ mv2

m/q = R2B2/2v

Sample inlet Ion Source mass analyzer detector Data aq.

Mean free pathMean free path, L = 1/nσ

n is number of molecules per unit volume

σ, the collision cross-section, relates to size

The Turbomolecular Vacuum PumpThe Turbomolecular Vacuum Pump

Attaches to MS flight tube ca 1 x 10-7 torr

To “rough” vacuum pump (ca 0.01 torr)

1 atm = 760 torr

1 x 10-7 torr = 76 millionths of

atmosphere

Turbine blades,65,000 rpmyou

When Ions fly, you generally don’t want them hitting gas molecules When Ions fly, you generally don’t want them hitting gas molecules

http://www.chem.vt.edu/chem-ed/ms/quadrupo.html

Quadrupole Mass AnalyzerQuadrupole Mass Analyzer

Ion source

Ion Trap mass analyzerIon Trap mass analyzer

Sample Inlet

“shutter electrode”

Detector

++ +

End End capcap

Ring Ring electrodeelectrode

RF

1. Fill trap2. Eject all but

target ion3. Use fields to

increase target ions energy until it fragments

4. Ramp end caps to get spectra of target fragment

5. Continue

1. Fill trap2. Ramp end

cap voltage3. Ions exit to

detector in order of mass

4. Refill trap for next scan Mass

SpectrumMSn

From “Ion Trap Mass Spectrometry” Wong and Cooks, http://www.currentseparations.com/issues/16-3/cs16-3c.pdf

Sequential Mass Spectrometry in the Ion Trap MSSequential Mass Spectrometry in the Ion Trap MS

(glycolipids are carbohydrate/lipid conjugates that occur in cell membranes)

Again, ALL Mass spectrometers must have:Again, ALL Mass spectrometers must have:

• sample inlet (atmospheric to high Vac.)• Ion source• mass analyzer• detector• data acquisition (and inst. Control and library searching )

Next, we’ll look at the three most common ion sources • Electron impact• Chemical Ionization• Electrospray ionization

3. B. Ion Sources3. B. Ion Sources

3. How does MS work?3. How does MS work?

1. Electron Impact (EI)2. Chemical Ionization (CI)3. Electrospray Ionization (ESI)4. Atmospheric Chemical Ionization (APCI)5. Matrix-assisted Laser Desorption (MALDI)6. Inductively coupled plasma Discharge (ICP)7. Desorption Electrospray Ionization (DESI)

(Plus a half-dozen more that are no longer commonly used).

No.s 3-7 also double as sample inlets

e- + M M

+ + 2 e

- (ionization potential

9 – 20 eV}

M+* F1+ + N1

F2+ + N2

Etc.“Fragmentation”, giving the mass spectrum of the molecule.

1. Electron impact ionization

Excess energy in molecule-ion?

(5 amps) MM+ M

M

M

+

V

10 to 100 V

M+filament

To mass analyzer

Isotope peaks

Isotopes, Molecular ions, and Fragments

75.8% of natural Chlorine atoms are atomic weight 35 25.4% are atomic weight 37.

Mass Spectrum shows:• Two molecular ions in 75.8 / 25.4 ratio.• Chlorine-containing fragments in same ratio (note m/z 47/49).• Hydrocarbon fragments clearly lack this (27/29? Nope)

(vinyl chloride)

http://www.cem.msu.edu/~reusch/VirtualText/Spectrpy/MassSpec/masspec1.htm

True Peak Shape on Quadrupole MS (Ben)Pkwdth_080919110220 #67 RT: 1.12 AV: 1 NL: 9.77E6T: {0,0} + p EI det=302.00 Full ms [ 15.00-300.00]

146 147 148 149 150 151 152 153 154

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Isotope peaks

M+1, m+2,etc.

It all comes from thermodynamics and kinetics

Stable CO2 molecular ion dominates spectraFrags present but small.

Lots of fragments in these but quite different spectra for similar compounds.

Interpretation of EI mass spectraInterpretation of EI mass spectraBefore computers…. • Many long hours spent correlating spectra to molecular

structure to develop predictive correlations.

• Hero’s spent their lives recording spectra of thousands of compounds relevant to their work.

• Positive id of an analyte required comparison with spectra of authentic standard on same MS at same time.

Since about 1975….Computer-searchable libraries of mass spectra …225,000 entries

Search results list 10 or 25 most probable compounds.

Chromatographic inlets add retention time information.

If you’re going to court, positive id of an analyte still requires comparison with spectra of authentic standard.

042409_Axe_sunset_Day_37C_gas_ long_2 4/24/2009 2:23:09 PM Axe Sunset (Day) 37C - Gas (pierced can)

RT: 29.45 - 30.90

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TIC MS 042409_Axe_sunset_Day_37C_gas_ long_2

042409_Axe_sunset_Day_37C_gas_ long_2 #4081 RT: 30.77 AV: 1 SB: 5 21.89-21.92 NL: 3.28E5T: + c Full ms [ 30.00-350.00]

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143.3

91.4128.3

“Send to library”

Library Search OutputLibrary Search OutputScreen photo…software dosen’t permit copying to other files

If not the actual compound, probably chemically related

2. Chemical Ionization, a gentle ionization2. Chemical Ionization, a gentle ionization

A. Formation of reactant ion (methane, for example). (E.I. at higher pressure of methane….ca 1 torr)

CH4+ + CH4 CH5

+ + CH3.

C2H5+ + H2 + H+ B. Reaction with sample molecule.

CH5+ + M MH+ + CH4 ∆E

Excess energy now limited by ∆E Excess energy now limited by ∆E • less excess energy in MH+ • spectrum simplified, often to MH+ only.

This is shown mainly as an example of the fact that various types of reactive chemistry can be studied or used in the ion source!!

3.3. Electrospray Ionization: Electrospray Ionization: an even more gentle technique.an even more gentle technique.

→ Perhaps most important development in MS ever (MALDI?).

→ Expanded upper mass limit to 100s of thousands 100s of thousands for peptide/protein and synthetic polymer work.

→ Permitted study of protein structure/function in new field of proteomicsproteomics.

→ Also useful for many other non-volatile compounds in the 1000 – 4000 AMU M. Wt. range (lipids, triglycerides,.etc.)

Biochemical and polymer applications of ESI first developed by Prof. John Fenn, Yale U. 2002

3. Electrospray Ionization, continued3. Electrospray Ionization, continued

0.001 to 2 ml/min liquid flow(e.g. from HPLC)

Vac. Pump10-5 torr

Vac. Pump10-2 torr

Mass Mass spec spec ion ion opticsoptics

+ +

+ + + +

+ + +

++

+

50 µ

+ + +

++

+

5 µ?

++++

++

1. Aerosol evaporation builds charge density

+ + ++

++ +++

++ +

+ +

++

+++

++

++++

2. Droplet stabilizes charge by distorting

++

+ + ++

++ +++

++

+ + +

++

+++

++

++

++

3. Droplet ejects ions by coulombic explosion

BTW… the aerosol tipMetal syringe needle (for gas)

Silica capillary for sample solution (HPLC?)

+ 4000eV

50 100 150 200 250 300 350 400 450 500mass

50000

100000

150000

200000

250000

Inte

nsity

Very gentle, only molecular ions in spectrum

Credit: Zina Deretsky, National Science Foundation

http://www.thermo.com/com/cda/resources/resources_detail/1,2166,200553,00.html

Sequencing of peptides separated by 2D-gel Sequencing of peptides separated by 2D-gel electrophoresis of digests “creature” materialelectrophoresis of digests “creature” material

Sample Needed for ESI-MSSample Needed for ESI-MSnn

(This is a comfortable amount for service work…not to be confused with detection limits)

Dry Sample* (preferred) In Solution Protein/Peptides   1µg   1µg/100µL (0.001% or 10 ppm) Polymers   1 mg   1mg/250µL ( 0.4%) Dendrimers  1 mg   1mg/250µL  Organometallics  1 mg   1mg/250µL  Organics   1 mg   1mg/250µL•For quantitative measures, enough to weigh is more than enough for MS

These figures are more than enough for other types of MS

Sensitivity such as this is one of the principal advantages of MS over other chemical analysis techniques.

ESI mass spectrum of horse heart myoglobin (mass 16955 Da)ESI mass spectrum of horse heart myoglobin (mass 16955 Da)

www.chm.bris.ac.uk/ms/theory/esi-ionisation.html

So why does a 16,955 Da protein give a spectrum with these low masses?

The key is that all mass spec interactions are on the basis of m/q ratio(16955 Da + 12 protons) / 12 charges = mass 1413.9(16955 Da + 13 protons) / 13 charges = mass 1305.1(16955 Da + 14 protons) / 14 charges = mass 1212.1etc. Note general accuracy for weighing this molecule goes to 5 sig. figs.

How Does MS Work - SummaryHow Does MS Work - Summary1. All MS must have combination of these key components:

Sample inlet Ionizer Mass Analyzer

Detector Control and data

Batch Electron Impact

Magnetic sector

Faraday cage PC

Direct Probe Chem. Ionization

Quadrupole Photoplate

GC ESI Quad Ion Trap

Electron Multiplier

HPLC MALDI Linear Ion Trap

Capillary ICP ICR (FTMS)

APCI ToF

Photoionization

Orbitrap

DESI Hybrid combinations

2. Table only includes most common types…there are many others out there.

How to provide a tour of mass How to provide a tour of mass spectrometry ?spectrometry ?

1. Introduction1. What is MS2. Who am I to say3. What do they look like4. Who uses MS and why

2. How does MS work1. Mass analyzers2. Ion sources

3. Details of some applications

Details of some applicationsDetails of some applications

1. Mass chromatograms used to find source of odor in pkg. material.

2. LC-MS to determine reason for “oily” antiperspirant package.

3. GC-MS to find cause of malodorous hair spray.

4. ESI-IT-MS2 to determine structural details of a cationic surfactant.

5. How LC-ESI-IT-MS2 is used in protein sequencing.

Example 1: Source of problem odor found by “mass chromatograms”.

Inlet:Inlet: GC-MS GC-MSMS:MS: Quadrupole QuadrupoleIonization: EIIonization: EI

Approach: Gas headspace analysis at sub-ppm concentrations

Sensitivity Required: Human nose sensitive to parts-per-billion parts-per-billion of some compounds

A 1 cc sample of air weighs about 10A 1 cc sample of air weighs about 10-3-3 grams grams A Quad GC-MS in good shape can detect picograms (10A Quad GC-MS in good shape can detect picograms (10-12-12 grams)grams)

1010-12-12 grams compound X grams compound X = 10 = 10-9-9 grams X per gram sample grams X per gram sample 1010-3-3 grams sample grams sample This is one part per billion This is one part per billion

Something smells funny here

http://www.cf.ac.uk/biosi/staff/jacob/teaching/sensory/olfact1.html

Odor is molecularOdor is molecular

CO

O

COH

O

Human nose: ppbHuman nose: ppb

At ppb level,At ppb level,

Hundreds of compoundsHundreds of compounds

Solid Phase Microextraction(SPME)

Absorbant coating such as GC stationary phase

PlungerSilica fiber

For concentration of sub-ppm organic analytes in air or water

SPME sampling of roll-on headspace?SPME sampling of roll-on headspace?

Malodor found to be due to polypropylene applicator ball by olfactory testing (i.e., they stunk and we had 200,000 of them)

Roll-on AP Applicators are hollow polypropylene spheres

Volatiles from polypropylene will tend to concentrate within sphere

GGas CChromatograph

MMass sspectrometer

time

GC-MS Inlet ConfigurationGC-MS Inlet Configuration

GC-MS (EI) Headspace Comparison of Polypropylene Balls

TIC MS

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NL:

ball6

NL:

“Good”

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1217.3215.4715.7014.73 18.84

16.84

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14.07

18.3712.61 13.59

1.78E7

TIC MS ball4

“Bad” Major differences

Minor, but interesting difference.

Remember…every second on chromatogram contains a complete mass Remember…every second on chromatogram contains a complete mass spectrum at that time. These are “total ionization chromatograms” (TIC)spectrum at that time. These are “total ionization chromatograms” (TIC)

Time (min)

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““good” mass 45 chromatogramgood” mass 45 chromatogram

12 13 14 15 16 17 18 190246

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““bad” mass 45 chromatogrambad” mass 45 chromatogram

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Examine “Mass Chromatograms” to check for sulfur compounds…almost any organosulfur compound will have a

CSH+ fragment in its mass spectrum

Tetrahydro-4-H-thiopyran-4-one

S

O

Library Library search search resultresult::

S

C

O

O

O

C18H37

C18H37 O C

O

CH2CH2 S CH2CH2 CH2 O

O

C18H37

Producer finally admits to presence of a sulfide Producer finally admits to presence of a sulfide free-radical scavenger:free-radical scavenger:

C

CH2

CH2S

CH2

CH2

C

OO

OO C18H37C18H37

Dieckmann Condensation, cf. Adv. Org. Chem., March, 4th Ed., 1992, p. 492

Polymer additive packages highly proprietary

Thermal decomposition analogous to decarboxylationThermal decomposition analogous to decarboxylation

generates compound found and sulfurous odor tied to “bad” polvpropylenegenerates compound found and sulfurous odor tied to “bad” polvpropylene

Example 2. Simple Approach Often Succeeds

• • Production QC Finds Malodorous Production QC Finds Malodorous Aerosol Hair Spray from Aerosol Hair Spray from contract fillercontract filler

• • Shipping on hold pending answerShipping on hold pending answer

• • Fast answer neededFast answer needed• • Remove button nozzle from top Remove button nozzle from top • • Fill gas syringe by depressing Fill gas syringe by depressing

spray tubespray tube

GC-MS (EI) Comparison of ReferenceGC-MS (EI) Comparison of Reference and Complaint Hair Sprays: and Complaint Hair Sprays:

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11.77

10.281.07

12.74

7.74

15.54

8.68

13.461.15

1.33

7.081.63

19.156.59

21.11 21.4616.036.34

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Ingredients: Aerosol Propellant

Solvent

Polymer

pH control

preservative

fragrance

• New formula under developmentNew formula under development• Antiperspirant sticks must maintain structure through 8 hr at 50 Antiperspirant sticks must maintain structure through 8 hr at 50 ooCC

Structured wax containing percent Structured wax containing percent levels of a small silicone oillevels of a small silicone oil

(Cyclopentadimethylsiloxane)(Cyclopentadimethylsiloxane)

Assumption was that this Assumption was that this silicone oil was separating and silicone oil was separating and leakingleaking

GC analysis proved otherwiseGC analysis proved otherwise

HPLC-APCI-MS was used to look at liquid

*

*

50 50 ooC Stability resultC Stability result

Example 3. The Case of the Leaky Antiperspirant StickExample 3. The Case of the Leaky Antiperspirant Stick

HPLC-APCI-MS of Antiperspirant StickHPLC-APCI-MS of Antiperspirant StickRT: 0.00 - 44.99 SM: 7B

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13.01 16.32NL:3.60E9TIC MS D850stick run 2

PPG-14-BEPPG-14-BE

Hydrogenated Castor OilHydrogenated Castor Oil

O

R1

R2

O C

O

(CH2)m CH CH CH2 CH

OH

(CH2)n CH3

When m=7 and n=8, the FA is ricinoleic acidWhen m=7 and n=8, the FA is ricinoleic acid

When R1 = R2 = ricinoleic acid, the triglyceride is castor oil, nominal When R1 = R2 = ricinoleic acid, the triglyceride is castor oil, nominal protonated M.Wt. 933.5protonated M.Wt. 933.5

Hydrogenated castor oil is a higher melting solid, castor waxHydrogenated castor oil is a higher melting solid, castor wax

Expanded View of LC-APCI-MS Chromatograms ofBulk Antiperspirant and Leaking Liquid

RT:13.39 - 24.13SM:7B

14 15 16 17 18 19 20 21 22 23 24Time (min)

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15.73

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NL:7.50E9TIC MS D850stickgunkrun2

NL:3.54E9TIC MS D850stick run 2Bulk antiperspirant

Leaking Liquid

Next slide Next slide shows shows composite composite mass spectra mass spectra of theseof these

D850stick run 2 # 513-595 RT: 15.10-17.06 AV: 83 SB: 30 2.65-3.65 NL: 1.67E8T: + c APCI Full ms [ 50.00-2000.00]

860 880 900 920 940 960 980m/z

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939.5

937.4

940.5

921.4935.4

919.4941.4

D850stickgunkrun2 # 534-603 RT: 14.75-16.40 AV: 70 SB: 30 2.41-3.28 NL: 1.77E8T: + c APCI Full ms [ 50.00-2000.00]

860 880 900 920 940 960 980m/z

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937.4

935.4881.7

938.4

939.4883.6 919.4

917.4

940.4920.4884.6879.7 899.5 921.4

O

R1

R2

O C

O

(CH2)m CH CH CH2 CH

OH

(CH2)n CH3

m/z 939.5: Fully hydrogenated

(bulk stick)

(leaking liquid)

Leak problem appears to result from separation

of castor oil (liquid) from solid wax structure.

Note intensity at M + 1.Castor oil (or wax) has 51 carbon atoms, each of which has 1.1% 13C

APCI Mass Spectra of Castor Wax Molecular Ion Region

Next example shows use of:• ESI• Ion Trap-MS• Collision-induced dissociation

For the purpose of structural characterization of a complex

surfactant used in a commercial hair conditioner.

N

MW = 494

Hydrophobic tail Hydrophilic head“Surfactant”:

Example 4. Structural Detail in Dicetyldimethylammonium chlorideExample 4. Structural Detail in Dicetyldimethylammonium chlorideCationic surfactant by MS/MSCationic surfactant by MS/MS

S#:

38-43 RT: 0.87-0.96 AV: 6 NL: 4.73E6+ p Full ms

250 350

400450 550

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369.4

438438452 480

494494

N

MW = 494

Cationic surfactants are key ingredients in hair conditioners.

silicone drople t

wax particle

Hair Conditioner Structure

lamellar ge lphase, Lb Hydrophobic tail Hydrophilic head

1. Form a gel structure to support insolubles in formula

2. Provide conditioning to hair (charge neutralization)Both of these functions chainlength dependant.Both of these functions chainlength dependant.

ESI mass spectrum of commercial material in ITMS

A mixture of many chainlengths!What is distribution?

Structural Detail in Dicetyldimethylammonium Cationic by MS/MSStructural Detail in Dicetyldimethylammonium Cationic by MS/MS

N MW = 494

S#:

38-43 RT: 0.87-0.96 AV: 6 NL: 4.73E6+ p Full ms

250 350

400450 550

0

10

20

30

40

50

60

70

80

90

100

Rel

ativ

e A

bund

ance

369.4

438438452 480

494494

MW 494 would be16/16, but could also be20/1218/1417/15 or any combination adding to 32 carbons.

16

/16

15

/16

15

/15

14

/15

14

/14

T: + p Full ms2 438.50

150

200250

300350

400450

500m/z

0

10

20

30

40

50

60

70

80

90

100

Rel

ativ

e A

bund

ance 214.3

256.4228.3

14/14 ?16/12

15/13

14/14

- C12

- C13

270.4 438.5

Distribution of chainlengths in “14/14” by Ion Trap MS-MSDistribution of chainlengths in “14/14” by Ion Trap MS-MS

Complete characterization automaticallyComplete characterization automaticallyData-dependant MS-MS of ions in spectra meeting selected criteria

Continued data-dependant selection and MS-MS of initial fragments.

Etc.

DESI MS for surface analysishottest new mass spec area

SurfaceSurface Analyte Analyte

Luggage Explosives residuesLuggage Explosives residues

SkinSkin Drug metabolites Drug metabolites

DrugTablets active ingredients DrugTablets active ingredients

Art work pigments Art work pigments http://www.prosolia.com/omnispray.html

cf. Cooks, et al, Science, 311, p1566, 2006

Ion source

sample

MS inlet

Desorption Electrospray Ionization

The “Mini-10” portable ion trap mass spectrometerThe “Mini-10” portable ion trap mass spectrometerPrototype in R.G. Cooks lab, Purdue Univ.Prototype in R.G. Cooks lab, Purdue Univ.

Boldly going where no mass spectrometer has gone before

Michael Pollitt The Guardian, Thursday 6 September 2007

The Future?

R.G. Cooks, et al, SCIENCE VOL 301 5 SEPTEMBER 2003

Soft Landing of mass resolved proteins

Soft-landed enzymes were shown to retain their structure/function after collection by measuring catalytic activity.

Low energy Low energy beambeam: losses losses by dispersionby dispersion.

High energy: High energy: Decomposition Decomposition upon crash upon crash landing.landing.

ComplaintSH_050630143722 T:- c ESI Full ms2 299.00@80.00 [ 80.00-500.00]

100 150 200 250 300 350 400 450 500mass

100020003000400050006000700080009000

1000011000

Inte

nsi

ty

263

264299

ComplaintSH # 173-186 RT: 4.81-5.17 AV: 14 SB: 19 0.21-0.73 NL: 2.95E5F: - c ESI Full ms [ 50.00-1500.00]

50 100 150 200 250 300 350 400 450 500wavelength (nm)

50000

100000

150000

200000

250000

Inte

nsity

299

301

263 333 335251

299 – 36

M- - HCl

Mass 97

HSO4-

16.0 16.5 17.0 17.5 18.0 18.5Time (min)

Geo

smin

40 PPT spike SPIKE

20 PPT spike SPIKE

Blank water

Plant water

Selected Ion Chromatograms (mass 112) of SPME Extracts of Headspace of the Indicated Samples

SPME-GC-EI-MS at ppt-level (1 part in 1012)“Musty-smelling” plant water

J.J. Thompson discovers isotopes, 1913

(Aston, 1919, 219 isotopes)

The language of mass spectrometry as used in this talk.

DaltonAMUIonIsotopeSample inletIon sourceMass analyzerIon trapQuadrupoleMagnetic sectorTurbomolecularMolecular ionFragment ionIsotopeBase peak

Mean free pathElectron impactElectrosprayChemical IonizationTotal ion chromatogramMass chromatogramGC-MSHPLC-MSDesorption ElectrosprayCollision-induced dissociation

American Society for Mass Spectrometry

2009 Asilomar Conference: Ion SpectroscopyAsilomar Conference Program

Invited Speakers & Titles

IONS AND WATER •Mark A. Johnson, Yale University; “Shape, Function and Reactivity of Water Clusters” •Richard J. Saykally, UC Berkeley; “pH of the Liquid Water Surface: Selective Adsorption of Hydronium and Hydroxide” PHOTOIONIZATION

•Andras Boedi, Paul Scherrer Institut; “First Results from the iPEPICO Endstation at the Swiss Light Source: The Surprisingly Complex Spectroscopy and Dissociation Dynamics of Small Molecules” •Laurent Nahon, SOLEIL Synchrotron, France; “Valence-shell Photoelectron Circular Dichroism on Gas Phase Pure Enantiomers Studied with Imaging PEPICO Techniques” •Ivan Powis, University of Nottingham; “Vibrational Effects in Photoionization Spectroscopy, with Particular Reference to Circular Dichroism Measurements” •Katharine Reid, University of Nottingham; “Challenging ZEKE: Applications of Photoelectron Velocity Map Imaging at High Resolution” UV/VISIBLE

•John P. Maier, University of Basel; “Electronic Spectroscopy of Astrophysically Relevant Ions” •Ricardo Metz, University of Massachusetts; “Electronic and Vibrational Spectroscopy of Intermediates of C-H: Activation by Metal and Metal-Oxide Cations” •Cheuk-Yiu Ng, UC Davis; “Spectroscopy and Dynamics of Neutrals and Ions by High-Resolution VUV and IR-VUV Laser Photoion-Photoelectron Methods” INFRARED •Evan Bieske, University of Melbourne; “Cold Complexes and Hot Particles – Mixing Laser Spectroscopy and Mass Spectrometry” •Michael A. Duncan, University of Georgia; “Cation IR Spectra Over a Wide Range: Hydrocarbons, Metal Carbonyls” •Gary Groenewold, Idaho National Laboratory; “IRMPD Studies of Uranyl Coordination Complexes” •Philippe Maitre, CLIO, Orsay France; “Gas Phase IR Spectroscopy of Inorganic and Organometallic Complexes” •Gerard Meijer, Fritz-Haber-Institut, Berlin; “Metal Clusters, Metal-oxides and Cluster-adsorbate Complexes” •Gilles Ohanessian, CNRS, Ecole Polytechnique; “Progress Toward the Accurate Modeling of IR Spectra of Oligopeptides” •Jos Oomens, FOM Rijnhuizen; “Anion Spectroscopy at FELIX” •Bela Paizs, DKFZ, Heidelberg; “Structure of Peptide Fragments from Computational and IR Studies” •Thomas Rizzo, EPFL Lausanne; “Conformation-specific Vibrational Spectroscopy of Cold, Biomolecular Ions” •Mary T. Rodgers, Wayne State University; “Probing the Effects of Cationization on the Structures of a Variety of Nucleobases, Model Phosphate Esters and the 2’-deoxymononucleotide-5’-phospha

Beginnings of Proteomic Book-keeping in Mass Spec

y1

y2

y3

b3

b2

b1

1. Determine peptide molecular weight from spectrum.

2. Y1 is AA ion fragment formed by loss of 1st AA from carboxy terminus.

3. B1 is AA fragment from cleavage at 1st amide from N-terminus.

Under CID, peptides will fragment at C-N bond of amide group(among other places).

MALDI IMAGING

References and “verified” information sourceshttp://www.cem.msu.edu/~reusch/VirtualText/Spectrpy/MassSpec/masspec1.htm

www.chm.bris.ac.uk/ms/theory/esi-ionisation.html

http://www.ionsource.com/ (proteomics tutorials and a lot more)

http://en.wikipedia.org/wiki/Mass_spectrometry (pretty good, especially with links)

R.G. Cooks, et al, SCIENCE VOL 301 5 SEPTEMBER 2003 (soft landing of proteins)

A mass spectroscopist is someone who figures out what something is by smashing it with a hammer and looking at the pieces.

Top-1 #426-539 RT:9.54-12.18 AV:114 SB:30 7.87-8.28, 12.96-13.19 NL:4.31E6T:+ c APCI Full ms [ 260.00-2000.00]

600 800 1000 1200 1400 1600 1800 2000m/z

510152025

3035404550

5560657075

80859095

100

Rel

ativ

e A

bund

ance

1298.51210.6

1342.51122.6

1400.61108.6

1064.61488.5

1020.5 1532.6

976.5

1620.51664.5

962.5 1708.6932.51722.61738.6

874.5 1796.6830.5

1870.51885.61900.6800.4

742.5698.4640.4

KA TRIN Experiment to Measure Mass of Neutron, Munster, GermanyKA TRIN Experiment to Measure Mass of Neutron, Munster, Germany

Illustrates that mass measurements on uncharged particles are much more difficult