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The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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Page 1: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

The world leader in serving science

iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

Page 2: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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• (1) Background and Workflows • (2) Peptide selection and standards • (3) Collision energy (CE) optimization • (4) Liquid chromatography (LC) gradient optimization • (5) Thermo Scientific™ TSQ Quantiva™ method editor

and parameter selection • (6) Experimental set up for peptide quantitation – an

example workflow • (7) Results • (8) Data processing with Thermo Scientific™

TraceFinder 4.1™

Application outline for peptide quantitation

Page 3: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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• (1) Background and Workflows • (2) Peptide selection and standards • (3) Collision energy (CE) optimization • (4) Liquid chromatography (LC) gradient optimization • (5) Thermo Scientific™ TSQ Quantiva™ method editor

and parameter selection • (6) Experimental set up for peptide quantitation – an

example workflow • (7) Results • (8) Data processing with Thermo Scientific™

TraceFinder 4.1™

Application outline for peptide quantitation

Page 4: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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Protein Quantitation with Confidence

• Goal: Addressing protein and peptide quantitation with the same ease as that of traditional small molecule quantitation

• Challenges: • Transitioning from traditional workflows for small molecules • Developing robust, sensitive, reproducible methods regardless of expertise • Addressing sample preparation complexity • Reducing cost/sample

• Confidence from Sample Preparation, LC-MS, to data analysis and reporting

Page 5: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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• Ensuring reproducibility is a critical challenge • Existing in-solution trypsin digestion of proteins is

• Time consuming • Requires multiple steps (protein assay, denaturation, reduction and alkylation) • Labor resulting in increased chances of errors, and lack of reproducibility

• SMART Digest Kit • Highly reproducible • Quick and easy to use • Detergent free • Less prone to chemically-induced PTMs • Autolysis-free • Amenable to automation

Sample Prep with SMART Digest Kit: Why?

https://www.thermofisher.com/order/catalog/product/60109-101

Page 6: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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Biologically interesting differentially expressed proteins PTM’s

Four basic components of Peptide Quantitation Quantifying with confidence multiple

targets Complex matrices Limited sample volume

Peptide Targets

Selection of peptides as surrogate candidates for protein quantitation

Peptide target optimization

Internal/externalstandard

Quantitation

SRM method

QQQ-based Quantitation

How Do We Get Started?

Challenge:

Page 7: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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• Immuno-purification

• Subcellular fractionation

• Chromatographic separation

Sample cleanup

Optimization Process

Biological Sample

Enrichment

Target Proteins

Target Peptides

Trypsin Digestion

Heavy peptides added for

quantitation

Final SRM-MS Method

SRM Method Optimization

• Gradient optimization

• RT Scheduling

• Transition refinement

• Internal Standard Spike Level

• Cycle Time

• CID Gas Pressure

• Collision Energy

• Run Standards

• Quantify targets in samples

• Process data

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• For the Top-Class QqQ available today, 10’s-100’s amol can be detected

Questions • How much total sample do you need to load to get this range

(or higher) of your target peptides? • What do you need to do to enrich your sample to get ~100

amol on column?

For Targets Without Empirical MS (Discovery data)…

Do the math!

Sample Enrichment Equivalent Sample Volume

Plasma Depletion (protein level) ~220 nL per inj.

Orthogonal Chromatography (peptide level) ~500 - 1500 nL per inj.

Antibody Enrichment (peptide level) ~100-1000 µL per inj.

1 ug neat plasma (no enrichment) ~ 15 nL

Page 9: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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• (1) Background and Workflows • (2) Peptide selection and standards • (3) Collision energy (CE) optimization • (4) Liquid chromatography (LC) gradient optimization • (5) Thermo Scientific™ TSQ Quantiva™ method editor

and parameter selection • (6) Experimental set up for peptide quantitation – an

example workflow • (7) Results • (8) Data processing with Thermo Scientific™

TraceFinder 4.1™

Application outline for peptide quantitation

Page 10: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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• Considerations: • Can you get multiple peptides from each

protein? • Do you need to look at site-specific

PTMs? • What do you do if you can only detect 1-

2 peptides per protein? • What do you do if the data from each

peptide for a protein give different quantitative results?

How Many Peptide Candidates per Protein is Ideal?

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If yes

Peptide Selection Criteria

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1Protein X

Differentially Expressed Proteins from DDA

Control

Experimental

Surrogate peptide candidates for quantitation

No peptides with Methionine*

Unique only to Target Protein?

Identified Peptides

Select higher abundance peptides

Good chromatographic

peak shape?

If yes

Multiple peptide targets per protein is ideal

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RT: 16.87 - 18.70

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17.4316.90 18.2918.0417.07 18.42

RT: 16.87 - 18.70

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Advantages of SIL Standards

Unlabeled

SIL

446.298m/z

609.360m/z

696.392m/z

797.440m/z

912.468m/z

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797.44 912.47

[ , , , ,

454.312m/z

617.374m/z

704.406m/z

805.454m/z

920.482m/z

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454.31

617.37

704.41

805.45 920.48

• Helps with ID due to same RT and fragment ratio pattern • Serves as Internal Standard for Sample Prep

• Each SIL spiked in at same concentration, every sample should have similar SIL Peak Area

• Using SIL’s for each peptide can improve precision (reproducibility) of quantitation

Page 15: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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Questions

Page 16: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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• (1) Background and Workflows • (2) Peptide selection and standards • (3) Collision energy (CE) optimization • (4) Liquid chromatography (LC) gradient optimization • (5) Thermo Scientific™ TSQ Quantiva™ method editor

and parameter selection • (6) Experimental set up for peptide quantitation – an

example workflow • (7) Results • (8) Data processing with Thermo Scientific™

TraceFinder 4.1™

Application outline for peptide quantitation

Page 17: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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• Large number of targets

• “Automated”

• Specific softwares (Skyline)

• LC multiple targets/run

Two methods for CE optimization

• Few targets

• Manual Optimization

• Direct infusion

• One target at a time

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Collision Energy (CE) Optimization

• On a triple quadrupole MS, each product ion is made separately by CID, and transferred to Q3 and the detector

• CE can be optimized for each Q3 product ion individually • Multiple product ions should be monitored in complex matrices

• Confirms peptide ID and provides a means to determine if there are interferences

http://www.nature.com/nmeth/journal/v9/n6/full/nmeth.2015.html

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CE optimization for large number of precursors

https://skyline.gs.washington.edu/labkey/wiki/home/software/Skyline/page.view?name=tutorial_optimize_ce

• Efficiently performed utilizing the LC system and software such as Skyline

• Start with >5 fmol on-column for nanoflow (above LOQ)

• Select fragment ions to target • If >10 peptides require CE

optimization, first find RTs for the LC method, then schedule CE optimization runs

• Most vendors provide a starting “CE regression equation” for their platform

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• TSQ Quantiva™ has the following recommended CE regression equations for peptides at CID gas pressure of 1.5 mTorr. • 2+ precursors: CE = m/z * 0.0339 + 2.3597

• 3+ precursors: CE = m/z * 0.0295 + 1.5123

• CE regression equations can be adjusted based on your peptide set.

Start with Recommended CE Regression Equations

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• Skyline generates the CE step gradient for each transition • Transition lists can be imported

into the TSQ Method Editor • Automatic Method Exports from

Skyline are available in TSQ v 2.1 software

• Product ion m/z is stepped in 0.01 m/z to associate steps in CE

• Large numbers of peptides (>10) may require scheduled methods for CE optimization

LC-SRM-MS Methods Can Be Generated and Imported

Page 22: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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• Import data for acquired CE optimization runs back into Skyline • Choose for “precursor” or “product” optimization (optimal CEs

may be different) • Save as a CE Optimization Library, and the settings will be

exported for all methods with these optimized peptides.

CE Step Gradient for On-Line Optimization

Precursor Level Optimization Product Level Optimization

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Automated CE optimization complete using LC

Optimal CE for Each Fragment

Page 24: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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Questions

Page 25: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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Select precursor m/z Quad resolution Optimize RF lens (best ion transmission for each precursor) Choose CID gas Pressure Collision energy range CE step number

Click optimize to start

Manual Tune Page Optimization

• Infusion-based approach

• Samples must be more concentrated and have some organic solvent for better ESI performance

• MS ramps voltages

• XICs are plotted to determine optimal settings

• PDF report is generated

• Optimized settings can be pasted into Method Editor

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Select Unknown Product Ions Top N (how many fragment ions to optimize) Low mass exclusion (doesn’t select ions below this m/z) Minor mass losses can also be excluded. Click on Edit Mass List, select masses to exclude.

Optimization Without Known Fragment Ions

Page 27: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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Example Optimization Report

Page 28: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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• (1) Background and Workflows • (2) Peptide selection and standards • (3) Collision energy (CE) optimization • (4) Liquid chromatography (LC) gradient optimization • (5) Thermo Scientific™ TSQ Quantiva™ method editor

and parameter selection • (6) Experimental set up for peptide quantitation – an

example workflow • (7) Results • (8) Data processing with Thermo Scientific™

TraceFinder 4.1™

Application outline for peptide quantitation

Page 29: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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Ion ratio confirmation in matrix background

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T 4

Neat Standard

Standard in Matrix 1fmole-PRTC2 #3262-3507 RT: 24.07-24.47 AV: 61 NL: 7.21E3F: + c NSI SRM ms2 422.432 [559.309-559.311, 674.329-674.331, 731.350-731.352]

559.310m/z

674.330m/z m/z

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PRTC-60mingrad #18130-18865 RT: 23.46-24.40 AV: 49 NL: 2.01E5F: + c NSI SRM ms2 422.432 [559.309-559.311, 674.329-674.331, 731.350-731.352]

559.310m/z

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• Ensure none of the target peaks have interference from the matrix background (peak splitting, shoulders).

• Modify the gradient to help shift interferences

If CE optimization done neat, check signal in the matrix

Short Gradient Long Gradient

Interferences resolving Interferences

closely eluting to target

Page 31: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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Goal: Maximize the time between targets and minimize the effect of the background matrix, while eluting in the shortest time possible.

Optimization of LC gradient

Gradient Length

Chromatographic Resolution

Sensitivity Reproducibility Sample Throughput

Short

Long

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Time (min)

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Page 32: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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• (1) Background and Workflows • (2) Peptide selection and standards • (3) Collision energy (CE) optimization • (4) Liquid chromatography (LC) gradient optimization • (5) Thermo Scientific™ TSQ Quantiva™ method editor

and parameter selection • (6) Experimental set up for peptide quantitation – an

example workflow • (7) Results • (8) Data processing with Thermo Scientific™

TraceFinder 4.1™

Application outline for peptide quantitation

Page 33: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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Method Editor for Thermo Scientific™ TSQ Quantiva™

Page 34: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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Method Editor for Thermo Scientific™ TSQ Quantiva™

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Parameter Selection for Targeted Peptide Quantitation Set chromatographic peak width

Use cycle time for best sampling frequency

Set cycle time to get 10-15 points across the peak

If RF Lens was not optimized for each target, use calibrated value

Q1 and Q3 Resolution can be individually set for targets in the SRM table, or globally here

Choose the CID gas pressure you optimized with

Chromatographic Filter provides “on the fly” signal averaging

Features new to

v2.1 software

Page 36: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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Use the peak widths from narrowest target peaks (at lower concentrations).

peak width cycle time 9.6 seconds/0.64 seconds = 15 scans

Cycle time determination

= Scans across the peak

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0.7 u

Note: 0.7 FWHM is equivalent to 1.0 mass width at base of peak (m/z scale)

Quadrupole Unit Resolution (0.7 FWHM)

Page 38: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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The Effect of Q1 Resolution on Intensity

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30Time (min)

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9.32 19.4917.2018.82

21.5720.3815.089.92 23.009.02 12.4310.067.951.61 25.60 26.507.77 27.3825.46 28.097.031.94 5.213.211.2616.03

13.49

17.269.37 19.5218.87

18.1515.119.95 20.419.06 23.0412.49 21.628.10 10.101.61 7.736.981.76 27.24 28.1926.6423.54 25.24 29.015.753.091.4216.06

13.52

17.29

19.539.4014.07 18.929.98 15.1412.509.068.23 20.9510.15 21.857.85 23.061.64 23.286.93 27.70 28.8927.021.81 5.25 25.743.590.46

NL:1.20E7TIC MS 040815_SSP_HLnoHeLa_BRIMSQ_PF_0-7Res_005

NL:7.12E6TIC MS 040815_ssp_hlnohela_brimsq_pf_0-4res_007

NL:1.94E6TIC MS 040815_ssp_hlnohela_brimsq_pf_0-2res_012

Q1 = 0.7

Q1 = 0.4

Q1 = 0.2

• PRTC peptide mix spiked into HeLa and analyzed with the same gradient and method, only Q1 resolution was changed

unit resolution

narrower isolation width

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Isobaric Discrimination – Effect of Increasing Resolution

m/z

100

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115.7 183.7

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115.7

Unit Resolution isolation

*

*

*

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166.7 182.7 250.1

Hi Resolution Isolation m/z 250.1

Q1 set to pass only sulfonamide

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SRM vs HSRM

RT :0.00-42.26

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NL: 1.27E3 TIC MS F: GISNEGQNASIK[HeavyK]:+ c NSI SRM

ms2 613.317 [355.242-355.244, 540.322-540.324, 725.402-725.404,

854.444-854.446, 968.487-968.489, 1055.519-1055.521]

200amolPRTC_11

NL: 3.58E2 TIC MS F: GISNEGQNASIK[HeavyK]:+ c NSI SRM

ms2 613.317 [355.242-355.244, 540.322-540.324, 725.402-725.404,

854.444-854.446, 968.487-968.489, 1055.519-1055.521]

200amolPRTC_HSRM_10

SRM

H-SRM

• 200 amol on column GISNEGQNASIK[HeavyK] • While the signal drops with Q1 setting of 0.2, the

background and chemical noise are drastically reduced

Q1 = 0.7

Q1 = 0.2

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Parameters to consider- Dwell Time

• Increasing Dwell Time improves S/N by increasing ion statistics

• Reproducibility of signal is also improved

• Dwell Times of 10 msec or greater provide high quality data for low abundant analytes

• TSQ Quantiva™ can detect signal with dwell times as low as 1 msec

• RT scheduling will increase dwell times vs unscheduled SRM methods

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Dwell time can be variable using cycle time

cycle time # product ions

= dwell time per fragment

0.5/10 = 0.05 seconds

0.5/50 = 0.01 seconds

• Minimum dwell time should be 10 milliseconds for low abundance targets.

• Shorter dwell times have poor ion statistics and can make quantitation more difficult.

• We want to have optimal chromatographic resolution of targets and minimal RT overlap.

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Determining Cycle Time when “setting” Fixed Dwell

• Elapsed scan time of 18 ms for 8 transitions • 18 ms / 8 transitions = 2.25 msec dwell time per transition • With a setting of 1 ms dwell, an interscan delay of ~1.25 ms is calculated • Elapsed scan time of 18 ms x 10 peptides = ~180 ms Cycle Time

• Note: The interscan delay will be dynamic and specific to the mass jump

Method: 1 ms Fixed Dwell Transition List: 10 Peptide, 8 transitions each (80 Transitions total)

Scan Header

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• (1) Background and Workflows • (2) Peptide selection and standards • (3) Collision energy (CE) optimization • (4) Liquid chromatography (LC) gradient optimization • (5) Thermo Scientific™ TSQ Quantiva™ method editor

and parameter selection • (6) Experimental set up for peptide quantitation – an

example workflow • (7) Results • (8) Data processing with Thermo Scientific™

TraceFinder 4.1™

Application outline for peptide quantitation

Page 45: Best Practices for Peptide Quantitation on a Triple ... · The world leader in serving science iQuan: Best Practices For Peptide Quantitation On a Triple Quadrupole Mass Spectrometer

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Experimental Design Example for Peptide Quantitation Goal: To quantify >360 peptides in a single QqQ method • Sample Details

• HeLa Lysate Digest (Pierce, 88328) • 0.5 ug/uL

• Retention Time Calibration Peptides (Pierce, 88320) • Response curve from 25 amol-100 fmol/uL) • Light versions spiked at a fixed 10 fmol/uL)

• 6 x 5 LC-MS/MS Peptide Reference Mix (Promega, V7495) • Isoforms for each peptide ranged: 20 amol – 200 fmol/uL

• MS Qual/Quant QC Mix (Sigma, MSQC1-1VL) • 14 light and heavy peptides at various L:H ratios • Peptide concentrations ranged from 160 amol/uL – 300 fmol/uL

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• Discovery Experiment to Select Target Peptides • Top 20 data dependent acquisition on a QE HF

• 30K Resolution • Max fill time: 20 msec • AGC target: 1e6

Experimental Design Example for Peptide Quantitation

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• Balance RT windows and number of transitions

• Adjust MS parameters for best cycle time

• Optimize CE (optional)

Peptide Selection and Spectral Library Generation

0 5 10 15 20 25 30 35 4Time (min)

0

10

20

30

40

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60

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100

Rel

ativ

e A

bund

ance

21.44 22.97

20.45

18.9517.99 24.1613.87 26.789.09 14.07

12.1227.23

27.9511.84 29.31 31.23

11.43

31.5132.20

32.80 37.0537.828.642.83 6.311.56

Top 20 dd-MS2 Screen QE HF

• Select peptides from search engine results

• Import list into Skyline Software

Database Search Peptide Selection

• Generate Spectral Library • Select and refine peptide list • Export targeted list of

transitions

tSRM Method TSQ Quantiva

RT: 8.95 - 36.67

10 12 14 16 18 20 22 24 26 28 30 32 34 36Time (min)

0

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23.5321.66

21.0115.1520.04

13.5822.8513.93

18.90 23.6417.15

12.87

18.60 29.2316.93 27.3824.1818.3212.22 26.1411.44 35.7328.47 31.36 32.5830.00 34.289.48 10.77

NL:7.79E7TIC MS 071616_Quantiva_100_fmol_034

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• Trap-Elute configuration (Easy nanoLC 1000) • Trap column: Acclaim PepMap 100, 100 um x 2cm, 5 um beads • Analytical column: EasySpray PepMap, 75 um x 25 cm, 2um beads, 50°C.

• Gradient • A = 2% ACN/0.1% formic; • B = 90% ACN/0.1% formic

• Total run time = 60 minutes

LC Conditions

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Targeted SRM for 361 peptides (1842 transitions)

RT: 8.95 - 36.67

10 12 14 16 18 20 22 24 26 28 30 32 34 36Time (min)

0

5

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30

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45

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75

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85

90

95

100

Rel

ativ

e Ab

unda

nce

23.5321.66

21.0115.1520.04

13.5822.8513.93

18.90 23.6417.15

12.87

18.60 29.2316.93 27.3824.1818.3212.22 26.1411.44 35.7328.47 31.36 32.5830.00 34.289.48 10.77

NL:7.79E7TIC MS 071616_Quantiva_100_fmol_034

• Cycle time = 1 sec • CID gas pressure = 1.5 mTorr • Q1/Q3 Resolution: 0.7/0.7 • RT windows: 2 minutes

• Chrom Filter = 8 • Collision Energy = optimized by

transition • Dwell time range = 3.5 – 125 msec • Total method time = 1 hour

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Questions

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• (1) Background and Workflows • (2) Peptide selection and standards • (3) Collision energy (CE) optimization • (4) Liquid chromatography (LC) gradient optimization • (5) Thermo Scientific™ TSQ Quantiva™ method editor

and parameter selection • (6) Experimental set up for peptide quantitation – an

example workflow • (7) Results • (8) Data processing with Thermo Scientific™

TraceFinder 4.1™

Application outline for peptide quantitation

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Reproducibility – Peak Areas

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Reproducibility – Peak Areas

0

2

4

6

8

10

12

14

16

0 0.025 0.1 0.25 0.5 1 2.5 10 25 100

% C

V (n

= 4

)

Heavy Peptide Concentration (fmol/uL)

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Reproducibility – Retention Times

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21.2 21.4 21.6 21.8 22.0 22.2 Time (min)

0

5

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21.50 21.44 21.56

• Eight XICs overlaid, show very good RT reproducibility

• SIL peptide is plotted

• Time range for shown data is 48 hours

• RT windows of 2 minutes were used, but could reduce to 1.5 or 1 min.

Reproducibility – Retention Times

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TSQ Quantiva™ : Consistent Sampling Frequency

21.0 21.2 21.4 21.6 21.8 22Time (min)

0

20

40

60

80

1000

20

40

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Rel

ativ

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ance

21.42

21.4421.41

21.4621.39

21.47

21.4921.37

21.4221.41

21.44

21.39

21.46

21.4721.37

NL: 2.26E5 TIC F: + c NSI cv=0.00 SRM ms2 769.888

NL: 2.50E4 TIC F: + c NSI cv=0.00 SRM ms2 773.895

~10 points across the

peak Light, 10 fmol

Heavy, 1 fmol

Most congested part of chromatogram

PRTC peptide ELGQSGVDTYLQTK

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Linear Response While Monitoring 1842 Transitions

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Linear Response While Monitoring 1842 Transitions

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Promega 6 x 5 Peptide Standard in 500 ng HeLa

200 fmol

20 fmol

2 fmol

0.2 fmol

0.02 fmol

Peptide LGFTDLFSK

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• (1) Background and Workflows • (2) Peptide selection and standards • (3) Collision energy (CE) optimization • (4) Liquid chromatography (LC) gradient optimization • (5) Thermo Scientific™ TSQ Quantiva™ method editor

and parameter selection • (6) Experimental set up for peptide quantitation – an

example workflow • (7) Results • (8) Data processing with Thermo Scientific™

TraceFinder 4.1™

Application outline for peptide quantitation

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Processing peptide SRM data with TraceFinder 4.1™

Fill with Picture or graphic

Fill with Picture or graphic

Peptide Support Simplify Method Development

Increase usability of Data Review

• Peptide predictor tool • Amino acid formula support • Import peptide and mass

lists from Skyline, Pinpoint

• Redesign/Update compound database, master method

• Autoscan filter selection • Ratio confirmations for all peaks

• Redesign/Update to include all peak information to review faster

• New advanced plots for peak review including group and batch plots Enhancing Quan Workflows for Routine Bio/Pharma applications

and Simplifying Method Development for all markets

Fill with Picture or graphic

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• Remember to follow key points when establishing your assay. • Careful selection of peptide targets, give yourself multiple options.

• Select m/z fragments above precursor and optimize CE’s for each.

• Optimize chromatography, ensure no interference with fragment ions.

• Utilize SIL internal standards if possible.

• Establish standards for endogenous protein concentration.

• Run “Scheduled” with RT windows when possible to maximize dwell

times.

• Ensure you have enough scans across the peak.

• Utilize ion ratio confirmation in your processing method.

• Quantitate utilizing fragment with best signal/noise.

Summary

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Susan Abbatiello Kristi D. Akervik

Brad Groppe Nick Molinaro Kent Seeley

Tara Schroeder Alan Atkins

Katie Southwick Detlef Schumann

Acknowledgements

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• http://www.proxeon.com/productrange/easy_spray/intro/index.html

Parts – Reversed Phase Columns

Part Number Description

Column Dimensions (ID x L)

Packing Phase Bead Diameter (µm)

ES800 EASY-Spray 75 µm x 15 cm PepMap C18 3

ES801 EASY-Spray 50 µm x 15 cm PepMap C18 2

ES802 EASY-Spray 75 µm x 25 cm PepMap C18 2

ES803 EASY-Spray 75 µm x 50 cm PepMap C18 2

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• https://www.thermofisher.com/order/catalog/product/160321

Parts – Reversed Phase Columns

Part Number Description

Analytical Column Dimensions (ID x L)

Packing Phase Bead Diameter (µm); Pore Size (Å)

164738 Acclaim 75 µm x 15 cm Acclaim PepMap 100 C18 3; 100

164739 Acclaim

75 µm x 50 cm Acclaim PepMap 100 C18 3; 100

164940 Acclaim

75 µm x 15 cm Acclaim PepMap 100 C18 2; 100

164941 Acclaim 75 µm x 25 cm Acclaim PepMap 100 C18 2; 100

164942 Acclaim

75 µm x 50 cm Acclaim PepMap 100 C18 2; 100

164568 Acclaim 75 µm x 15 cm Acclaim PepMap 100 C18 3; 100

164569 Acclaim 75 µm x 25 cm

Acclaim PepMap 100 C18 3; 100

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• https://www.thermofisher.com/order/catalog/product/160321

Parts – Reversed Phase Trap Columns

Part Number Description

Trap Column Dimensions (ID x L)

Packing Phase Bead Diameter (µm)

164535 Acclaim 75 µm x 2 cm PepMap 100 C18 3

164564-CMD also known as 164564

Acclaim 100 µm x 2 cm PepMap 100 C18 5

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Parts – Metal Needle Kits and Ion Source Accessories

Part Number Description

00950-00954 32-Gauge metal needle kit for high flow LC flow rates between 5μL/min to 400μL/min

97144-20040 34-Gauge metal needle kit for low flow LC flow rates between 500nL/min to 10μL/min

00106-10511 Tubing, 0.075mm ID x 0.193mm OD fused-silica capillary for low flow applications instead of metal needle

ES232 EASY-Spray Emitter Positioning Tool

ES235 EASY-Spray Emitter Wash Cap

106868-0064 Cleaving Stone, 1" x 1" x 1/32”