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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.
Recommended