Selected ion flow tube MSOnline quantitative VOC analysis

Dr. Joeri VercammenManaging Expert IS-X

www.is-x.com

“DIRECT MS TECHNIQUES”

Ease-of-use

Speed

Price

Sensitivity

Separation power

Identification of artefacts

DART-MS

Ionization technique that

uses metastable He* to

ionize surface analyte

molecules.

i-KNIFE

Rapid evaporative ionization MS of phospholipids to discriminate

between cancerous and non-cancerous cells.

MS-NOSE

Direct injection of food headspace

into a classic electron impact

source.

Strong ionization reduces sensitivity

& identification capabilities.

Ideal for rough characterization.

SIFT-MS

Direct injection of food headspace

into a room temperature SIFT

flowtube.

Soft chemical ionization preserves

sensitivity and allows selective

identification capabilities.

Knowledge of reaction kinetics allows

absolute quantification.

1976

First SIFT instrument described by David Smith (UK).

Study kinetics of ion/molecule reactions in interstellar

clouds.

Low Tk?

Known signals & concentrations

of I +, A and P+ are used to

calculate reaction rates…

I+ A P+

1996

Trace analytical technique.

Calculate concentrations from:

Reaction schemes

k-Values

1997 2001

2014SIFT-MS detects & quantifies trace amounts of volatiles,

Analysis in real time

Volatile organics & inorganics

Low PPB level sensitivity

725

875

900

How does it work?

Precursor ions, generated in-situ

H3O+, NO+, O2+,selected by Q1

Chemical ionisation,Flow tube

Separation & detection of product ions by Q2

Chief characteristics

SIFT-MS has several unique features,

CI with multiple precursor ions results in unique

selectivity

Absolute quantification due to thermalized conditions

Designed for ultra-sensitive applications

The possibility of three CI agents increases confidence,

Acetone 59 88 43, 58

Mw 58

Propanal 59 57 57, 58

Mw 58

H3O+ NO+ O2+

Selectivity

Absolute quantification

Analysis time & sample gas flowrate

Reagent and product ion (absolute) signals

Rate coefficient of the reaction

[ 𝐴 ]=¿¿

Ultra-sensitivity

Detection limits in the sub PPB range.

Inert flow path from sample to flow tube

Zero blank levels

No source contamination

Target compounds

Compound Class Compound Class

Alkanes Nitrogen heterocycles

Alkenes and dienes Nitrated organics

Alkynes and diynes Oximes

Aromatic hydrocarbons Nitriles

Terpines Halogenated alkanes and alkenes

Alcohols and diols Halogenated aromatics

Aldehydes and dialdehydes Miscellaneous halogenated organics

Ketones Thiols

Carboxylic acids Thioalcohols

Esters Thioacids

Ethers Thioethers

Cellosolves Sulfur heterocycles

Oxygen heterocycles Sulfoxides

Epoxides Organophosphorus compounds

Amines Inorganics

Amides

Applications

Common applications,

Environmental analysis

Clinical applications

Food & flavour analysis

Control of raw materials

Process control

On-line analysis

In-situ analysis

Packaging control

Food applications

CASE 1:CONTROL OF RAW MATERIALS

Aldehydes in malt

“Aldehyde precursors determine the shelf-live of pilsener beers”

Complex analytical procedure

Tedious

Not applicable on-site

Malt A-2

Malt B1-1Malt B1-2

Malt B2-2

Malt B2-1Malt B3-2

Malt B3-1

Malt C-1Malt C-2

Malt A-1

hexanal

2-methylbutanal

3-methylbutanal

methional

2-methylpropanal

trans -2-nonenal

benzaldehyde

phenylacetaldehyde

furfural

Malt B1

Malt C

Malt A

hexanal

2-methylbutanal

3-methylbutanal

methional

furfural

2-methylpropanal

trans -2-nonenal

benzaldehyde

phenylacetaldehyde

Malt B2

Malt B3

GC-MS analysis

SIFT-MS analysis

Aldehydes in malt

“Identify premium quality and defective carcases”

Meat aroma testing

PC2

PC1

PC3

SOO 1-5

SOO 6-10

SOO 11-15

SOO 16-20SOO 21-25

SOO 26-30SOO 31-35

SOO 36-40

Rotten R4

R High pH R1R High pH R2R High pH R3

R High pH R4R High pH R5

QM High pH R4

R Norm pH R1R Norm pH R2R Norm pH R3R Norm pH R4

R Norm pH R5

Cow 1 R1Cow 1 R2

Cow 1 R3Cow 1 R4Cow 1 R5Cow 2 R1Cow 2 R2Cow 2 R3Cow 2 R4

Cow 2 R5

Bull 3 R1Bull 3 R2

Bull 3 R3

Bull 3 R4

Bull 3 R5

Bull 4 R1Bull 4 R2Bull 4 R3

Bull 4 R4Bull 4 R5

Rotten R1Rotten R2

Rotten R3Rotten R5

QM High pH R1

QM High pH R2QM High pH R3

QM High pH R5

PC1

PC2

PC3

R High pH R1R High pH R3

R Norm pH R1R Norm pH R2

R Norm pH R3

R Norm pH R4

Cow 1 R3

Cow 1 R4

Cow 1 R5

Cow 2 R1

Cow 2 R2

R High pH R2R High pH R4

R High pH R5

R Norm pH R5

Cow 1 R1

Cow 1 R2

Cow 2 R3

Cow 2 R4

Cow 2 R5

Expanded, rotated view

CASE 2:PROCESS CONTROL

“Coffee beans crack twice during roasting”

Chemical and physical transformation

165°C (drying phase)

225°C (full city roast)

Coffee bean roasting

Coffee bean roasting

CASE 3:ONLINE ANALYSIS

“On-line monitoring of fermentation metabolites”

Better control of industrial production

Detect action of undesirable microorganisms

Difficult by GC/MS

Fermentation

Fermentation

Fermentation

EthanolAcetoinAcetic acid

“Warning system + product quality monitoring”

Spray drying of dairy products

Explosion risk monitored with CO monitor

Frequent false alerts

Milk powder drying

0

50

100

150

200

250

0

500

1000

1500

2000

2500

0 2 4 6 8 10 12 14 16 18

Tem

pera

ture

/ o

C

Conc

entr

ation

/ p

pb

Time / minutes

acetic acidacetaldehydecarbon monoxideoven temperature / C

Skim Milk Powder

Milk powder drying

80

90

100

110

120

130

140

150

160

170

180

190

69

1316

0

50000

100000

150000

200000

250000

300000

350000

400000

Inte

ns

ity

/ c

ps

m / z

Time / min.

acetic acid

dimethyl sulfone

hexanoic acid

furfuryl alcohol

propanoic acid

norfuraneol

butanoic acid

maltolfuraneol

pentanoic acid

heptanoic acid

octanoic acid

nonanoic acid

CASE 4:IN-SITU ANALYSIS

“Determine the contribution of in-situ generated volatiles”

Place product in mouth

Chew: exhale & inhale

Swallow: exhale & inhale

In-mouth analysis

0 10 20 30 40 50 60 70 80 900

50

100

150

200trans-2-Hexenal

cis-3-Hexenal

Hexanal

Time (sec)

Conc

entr

ation

(ppb

)

Swallow

In-mouth analysis

In-mouth analysis

0 10 20 30 40 50 60 70 80 900

5

10

15

20

25

NonanalIsobutyl alcohol Methylbutanal

Time (min)

Conc

entr

ation

(ppb

)

Swallow

“Benchmark for product acceptability”

Expensive

Subject to fatigue

Off-line process

Sensory testing

Sensory testing

PC1

PC2

PC3

NZG1NZG1

NZG2NZG2

NZG3NZG3

NZP1

NZP1

NZP2

NZP2NZP3

NZP3

NZF2

PRA4

PRA5

PRA5

GPA3

GPA3

GPA5

NZF1NZF1

NZF2NZF3

NZF3

NZK1NZK1

NZK2

NZK2

NZK3NZK3

GPC1GPC1GPC1GPC2

GPC2GPC2 PRC1

PRC1

PRC1

PRC2PRC2

PRC2

PRA3

PRA3

PRA4

GPA4

GPA4

GPA5

CASE 5:FOOD PACKAGING

“Malodourous contamination at the exterior from mixed transport”

Chlorophenols

Bromophenols

Trichloroanisole

Packaging contamination

Conclusion

The Voice200 is a user-friendly instrument that allows rapid

analysis of aroma components without preconcentration and

discrimination.

Simple, non-destructive analysis

Analyze all polarities at once

No artefacts

A multisensor instrument with GC/MS functionality.