gc-hrms and gc×gc-hrms: tackling the identification ... · gc-hrms and gc×gc-hrms: tackling the...

GC-HRMS and GC×GC-HRMS: tackling the identification

challenges in complex matrices

Daniela Peroni

JSB Netherlands

JSB Group

• Agilent Technologies Value Added Reseller (VAR).

• Knowledge partner in chromatography and mass spectrometry solutions.

• Providers of custom-made systems.

• Specialist in GC×GC.

• Offices in the Netherlands/UK/Belgium/Germany.

• Demo lab (Lelystad, NL).

Outline

• GC-QTOF

• Targeted search in complex food samples analysis.

• Advantages for samples with broad concentration range.

• GC×GC-QTOF

• Targeted search in complex food samples analysis.

• Fingerprinting of complex food samples.

• Age markers in diesel oil samples.

• Visual group characterization of petrochemical samples.

Allyl isothiocyanate

Butyl isothiocyanate

PhenylethylisothiocyanateButenyl

isothiocyanate

Lynalool3-Methylthiopropylisothiocyanate

GC-QTOF applications: mustard

SPME of head-spaceSplit 1:10HR mode

EIC – Accurate mass

EIC - Nominal mass

Targeted search: benzyl isothiocyanate


TIC

Targeted search: benzyl isothiocyanate

142.0929± 10 ppm

142.0± 0.5 m/z

149.0299 ± 10 ppm

149.0 ± 0.5 m/z

Estragole(M+1)+,C10H12O,

149.0911 m/z

Anethole(M+1)+, C10H12O,

149.0910 m/z

149.0295 m/z



MS Interpreter (connected to the NIST library search).

trans 2-Hexenal

trans-4-Hexen-1-ol

2,4-dimethyl-hexane

2-Hexen-1-ol

2-Heptenal

trans-Decenal

Citral

From SPME fiber

Commercial olive oil (supermarket)

Artisanal olive oil (Italy) trans 2-Hexenal

2-Hexen-1-ol

GC-QTOF applications: olive oil

SPME of head-space, split 1:10HR mode


Fragment (nominal)

Theoreticalformula

Exact massMeasuredmass

Formulaproposed

Hit #Error (ppm)

97,0C6H9O+(loss of CH3)

97,0653 97,0648 C6H9O+ 1 <0,1

83,0C5H7O+(loss of C2H5)

83,0497 83,0497 C5H7O+ 1 0,5

69,0C4H5O+(loss of C3H7+)

69,0335 69,0340 C9H13+ 1 - 1,6

2-Heptenal

Vanillin

Piperonal

Guaiacol

p-Creosol

Vanillyl ethyl ether

Vanillyl alcohol

GC-QTOF applications: vanilla extract

Liquid injectionSplit 1:10EDR mode


Very good spectral qualityNo spectral skewingGood library match


S/N=392

S/N=3,7

GC×GC-QTOF - Mustard

HR mode

Allyl isothiocyanate

3-methyl isothiazole

Acetic acid

Phenylethyl isothiocyanate

EstragoleButenyl isothiocyanate

Linalool

Butenenitrile

SPME of headspace, Split 1:10HR mode


Selected Ion Chromatogram (SIC) for 163.04557±0,01 m/z

Targeted search: phenylethyl isothiocyanate


Targeted search: phenylethyl isothiocyanate


Coeluting in 1D,fully separated in 2D

Identification of unknown

GC×GC-QTOF - Tea leaves

Lemon green tea

Black tea

Strawberry tea

SPME of head-space, split 1:5HR mode

Visual comparison – qualitative fingerprinting

GC×GC-QTOF - Tea leaves

Lemon green tea vs. Strawberry tea (reference)• Green peaks: more abundant• Red peaks: less aboundant

Key differeces are vizualized in a quick, easy way.

GC×GC-QTOF - Tea drinks

Lemon green tea

Black tea

Strawberry tea

SPME of head-space, split 1:5EDR mode

GC×GC-QTOF - Tea drinks

split 1:5EDR mode

Lemon green tea

GC×GC-QTOF - Tea drink

Methyl cinnamate

2-Decanal

Citral

Caryophyllene

Decadienal

2-Undecenal

Strawberry tea

VerbenolAnethole

Citral

Aromadendrene

CaryophylleneDecadienal

Linalyl acetate2-Decanal

Lemon green tea


Linalyl acetate:

Fragment (nominal)

Formula suggested byMS Interpreter

Exact mass

Measuredmass

Formula proposedby GC Image

Hit #Error (ppm)

196,0 C12H20O2+ (M+) 196,1458 196,1458 C12H20O2+ 10,2

154,0 C10H18O+ (loss of C2H3O) 154,1358 154,1352 C10H18O+ 1 0,2

136,0 C10H16+ (loss C2H4O4) 136,1252 136,1247 C10H16+ 1 1,6

121,0 C9H13+ (loss C2H4O4+CH3)121,1017 121,1012

C9H13+ 11,6

Structure confirmation: mass accuracy of multiple fragments.


Targeted Template Matching

Lemon green tea


Targeted Template Matching

Strawberry tea


Untargeted Template Matching: all peaks detected are in the template.

Lemon green tea

Strawberry tea


Untargeted Template Matching

GC×GC-QTOF – Petrochemical samples

Age markers in diesel oil

The C17/pristane ratio gives an indication of the oil degradation.


Age markers in diesel oil

NIST

NIST

GC×GC gives cleaner spectra.Better for identification!


Colorization of groups in diesel oil (GC Image)


Extra selectivity thanks to accurate mass.

Nominal mass

Accurate mass

Colorization of groups in diesel oil (GC Image)

gc-hrms and gc×gc-hrms: tackling the identification ... · gc-hrms and gc×gc-hrms: tackling the...

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