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Fourier Transform Ion Cyclotron Spectrometry What is Mass Spectrometry?

Gravity m r 2 F= G⋅m⋅M/r M

Newton’s second law F = m⋅a

Mass-Energy equivalence 2 Newton E = m⋅c Einstein 1 eV = ~10-9 amu A Mass Spectrometer

MagLab - Single Sector Mass Spectrometer Tutorial

MagLab - Dual Sector Mass Spectrometer Tutorial

Ion Cyclotron Motion

B v m m v + - qv x B qv x B r r

Marshall and Grosshans, Anal. Chem. 1991, 63, 215A. Centripetal 2 Magnetic Force m v r = q v B m v = q B r kinetic energy distance m ω = q B slit width q B

ω= 2πf = m Ion Cyclotron Resonance

100 ≤ m/z ≤ 3000 corresponds to 35 kHz ≤ f ≤ 1 MHz at 7 tesla Ernest O. Lawrence 1939 Nobel Prize in Physics

Donald Cooksey Cyclotron Accelerator FT-ICR Theory - Ion Trapping

X

Magnetic Field (B) Z T T Y

E

Axial Position FT-ICR Trap Geometry

E Y D B D E T Z T T T X E E D D

D D E T T,E T,E T D T E,D,T E T E D Excitation Detection fast (~1 ms) scan all m/z simultaneously

+ + + + + + + + +

B0

+

+

+ + R C +

+

+ + +

Marshall et. al., Mass Spectrom. Rev. 1998, 17, 1. Image Bovine Charge Ubiquitin Differential Amplifier 0

FT 80 240 400 FT-ICR Tutorial Time (ms)

10+ 10+ 9+ 9+ m B _ E = 2 8+ q f f 8+ 11+ 11+ 1071 1072 + + 7+ 12 12 7+

100 150 200 250 600 1000 1400 1800 (kHz) m/z f m Resolving Power (RP) = = Δf Δm

Magnitude-mode lineshape At 7 Tesla, RP is greater and Hanning apodization than 100,000 at m/z 500 for a 1 s observation

~2 Δf observation period (s) 50%

Frequency (Hz) (m/z)max - (m/z)min Peak Capacity = Δm50%

• • • Δm50%

m/z (m/z)min (m/z)max Advantages of High

Mass Resolving Power Mass Accuracy Acquisition Speed Dynamic Range 21 T Kinetic Energy* Peak Coalescence 14.5 T 21 T

12 T 9.4 T 14.5 T 7 T 12 T 7 T 9.4 T

0 B (tesla) 25 0 B (tesla) 25

Marshall and Guan, Rapid Commun. Mass Spectrom. 1996, 10, 1819-1823 Low Resolving Power m = 2500 Δm High Resolving Power

m = 350,000 Δm

563.25 563.35 563.45 563.55 563.65 563.75 m/z

RVMRGMR vs. RSHRGHR (MW ≈ 904 Da) Monoisotopic Mass (S2H8 vs. N4O) 0.000452 ± 0.000005 Da

m = 3,300,000 Δm m(e-) = 0.000548 Da

906.496 906.499 906.502 m (Da) Smallest resolved mass difference between two molecules! Middle East Crude Oil, (+) APPI at 14.5 T 2.3 mDa 3.6 mDa, C N vs. 13C 3.6 mDa 1 1 2 13 1.1 mDa 2.3 mDa, C7 vs. S2H7 C1 1.1 mDa, SH 13C vs. C 3 1 4 49,797 peaks >6σ

m/Δm50% = 800,000 (m/z 400) 3.4 mDa, 4.5 mDa, C3 vs. SH4 13C vs. CH 505.276 505.298

3.4 mDa

1000.04 1000.05

400 600 800 m/z 1000 1200 1400 Petroleum = Immense Complexity

105,817 peaks

500 750 1000 1250 1500 1750 2000 Molecular mass Centripetal Force 2 Magnetic Force m v r = q v B m v = q B r kinetic energy distance m ω = q B slit width q B

ω= 2πf = m Ion Cyclotron Resonance

100 ≤ m/z ≤ 3000 corresponds to 35 kHz ≤ f ≤ 1 MHz at 7 tesla E Field Contribution

E Y D B D E T Z T T T X E E D D

D D E T T,E T,E T D T E,D,T E T E D FT-ICR Mass Calibration: E & B Centripetal Force Magnetic Force Electric Force 2 m v r = qvB – qEr 2 m ω r = qBωr – qEr 2 m ω = qBω – qE

m = B – E q ω ω2

Ledford et. al., Anal. Chem. 1984, 56, 2744-2748. FT-ICR Mass Calibration

7 2

6 mω = Bω – E

) q 13 5 x 10

2 4

3 (Th Hz (Th

2 f 2 rms error = 251 ppb q m m/q = 300-800 1 n = 34

0 0 100000 200000 300000 400000 Frequency (Hz) Superconducting Magnet (B field) Stability 1400

1200

1000 2 ppb/hour

800

600

400

Magnetic Field Drift (ppb) Drift(ppb) Field Magnetic 200

0 0 100 200 300 400 500 600 Time (hours) Stability

80 30 ppm shift in E leads to 1 ppb mass shift! 7 T, m/z 500 60

40 ~8 Hz/V 20 Frequency Shift (Hz) FrequencyShift

0 0 2 4 6 8 10 Trap Potential (V) What is Molecular Mass?

Mass: M = Σme⋅ne, me – mass of an element ne – number of of this element in the molecule

Isotope Mass Abundance Chemical mass 1H 1.00782510 99.9852% 1.00794 2H (D) 2.01410222 0.0148%

12C 12.0(0) 98.892% 12.011 13C 13.0033544 1.108%

14N 14.00307439 99.635% 14.00674 15N 15.0001077 0.365%

16O 15.99491502 99.759% 15.9994 17O 16.9991329 0.037% 18O 17.99916002 0.204%

31P 30.9737647 100% 30.9737647

32S 31.9720737 95.0% 32.066 33S 32.9714619 0.76% 34S 33.9678646 4.22% 36S 35.967090 0.014% Want a 5 lb weight on the platform:

1 lb 2 lb 5 lb

Want a 10 lb weight on the platform:

# of possibilities depends on what? Now increase the # of blocks to the # of elements and their to atomic mass units.

The number of possibilities drastically increases as the mass of the molecule (or “weight on the scale”) increases and as the number of weights (or atoms) increases Now:

H He Li

and so on… But now everything doesn’t have a integer mass:

1 lb H = 1.0078 2 lb He = 4.0026 5 lb Li = 6.9410 So we have a “mass defect” imparted by every except carbon 12, since it is the base of the scale at 12.0000 One 12C and four H’s = For example: Methane 12.0000 + (4) x 1.0078 =

16.0312 not 16.0000, have a 0.0312 mass defect

This is why you can assign elemental compositions! (Dalton) 0.02 2H Atomic 13 1H C Mass Defects 0.01 14N 15N

0

12C -0.01 16O

-0.02

-0.03 31P 32 S 34S -0.04 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 Low resolution

High resolution

1 m/z This is the way nature works!

Low Resolution MS m = 2500 Δm High Resolution MS

m = 350,000 Δm

563.25 563.35 563.45 563.55 563.65 563.75 m/z How accurate do you have to measure the mass?

CcHhNnSsOo Mass Space 10 (1 mDa Bins)

8

6

4

2

0 521.0 521.1 521.2 521.3 521.4 521.5 Mass CcHhNnSsOo Mass Space

10 (1 mDa Bins)

8

6

4

2

0 521.10 521.105 521.110 521.115 521.120 Mass CcHhNnSsOo Mass Space

7 (0.5 mDa Bins) 6 5 4 3 2 1 0 521.100 521.105 521.110 521.115 521.120 Mass ~1 possibility per bin!

CcHhNnSsOo Mass Space

4 (0.1 mDa Bins)

3

2

1

0 521.110 521.112 521.114 521.116 521.118 521.120 Mass C / H12 93.9 mDa 13 C2 / C2H2 8.9 mDa

European Crude Oil 13 N C / C2H3 17.1 mDa (+) ESI FT-ICR MS

O / CH4 36.4 mDa

C3 / SH4 3.4 mDa N / 13CH 8.2 mDa

700.40 700.45 700.50 700.55 700.60 700.65 700.70

300 400 500 600 700 800 900 1,000 m/z Compositional Analysis of Heavy Conventional Crude Oil by FT-ICR Mass Spectrometry

m/Δm50% m/z 704.53510 100 - 400 ppb * + [C50H72S1 + H]

S1 Class 400 500 600 700 800 m/z 40

1. Carbon Number 30 2. Heteroatom Composition 20 3. Aromaticity DBE 10 H N DBE = C – + + 1 2 2 0 20 40 60 80 McLafferty & Turecek Int. Mass Spectra, 1993 Relative Abundance (% total) Carbon Number [Z = -2(DBE) + n + 2] Advanced Data Processing enables high throughput analysis…

Petro-Org Software Platform Petroleum: The Structural Controversy

2 Proposed Structural Motifs

Island Archipelago

N CH3

+ N H

Loss of DBE with Carbon

Energy & Fuels, 14 (1), 2000, 6-10 Distinction Between Structures 40

30

20 I DBE

10 A

0 0 20 40 60 80 Carbon Number Petroleum: The Structural Continuum

200 400 600 800 1000 1200 1400 1600 m/z DAO 4 Ring Fraction (+) APPI FT-ICR MS at 9.4 Tesla SWIFT Isolation at m/z 632

632.2 632.3 632.4 632.5 632.6

200 400 600 800 1000 1200 1400 1600 m/z DAO 4 Ring Fraction – Single Nominal Mass Isolation Quad Iso + SWIFT for m/z 632

S1

HC S2

S3 S1

S2 S3

S2 HC

S1 IRMPD 100 ms IRMPD 500 ms 40 40 HC Class HC Class 30 30

20 20

10 10

0 0 40 40 S1 Class S1 Class 30 30

20 20 Double Bond Equivalents Equivalents Bond Double 10 10

0 0 0 20 40 60 80 0 20 40 60 80 Carbon Number DBE 26

DBE 23

DBE 20

DBE 14 DBE 17

DBE 10

DBE 7

5 15 25 35 45 Carbon Number Thank You!

Ryan P. Rodgers Ion Cyclotron Resonance Program [email protected]