iso TOC cube: new innovations from a familiar company
Advances in Stable Isotope Techniques & Applications, University of Calgary
Tuesday June 4 th , 2013
Arthur Kasson, IRMS Product Manager elementar Americas Inc.
1

• Compact, bench-top IRMS
• 100% high purity stainless steel horizontal vacuum housing
• Extremely high vacuum conductance means only a single turbomolecular pump is required
•
100V dynamic range linear analyzer
• Robust thorium coated ionization filament
• 10 year warranty of Faraday Collectors
• Modular electronics for simple maintenance
• High stability electromagnet with no need for water cooling
• Fully automated analysis and diagnostics through IonVantage software
• Market leading performance specifications
2

IRMS
Sensitivity Absolute sensitivity of CO
2
(molecules/ion)
850 DI mode
1200 CF mode
H
3
+ correction factor
H
3
+ factor stability
Mass Resolution
< 8.0 ppm/nA
< 0.03 ppm/nA/hr
(10% valley definition) 100
Reference Gas
Gas
CO
2
N
2
H
2
Isotope
δ 13 C
δ 18 O
δ 15 N
δD
Internal Precision
1
σ ‰
≤ 0.06
≤ 0.06
≤ 0.06
≤ 0.20
Linearity
‰ / nA
≤ 0.02
≤ 0.04
≤ 0.02
-
3

Total Organic carbon (TOC) IRMS
Key Applications
The main applications for TOC are environmental forensics and ecology
1. River nutrient and food webs
2. Agricultural run off into water systems
3. Soil dynamics
4. Water quality analysis and pollution
5. Marine & estuarine dynamics
4

Total Organic carbon (TOC) IRMS
Unique Capabilities
1. Variable sample feeding
2. High temperature digestion with matrix separation (up to 1200C)
3. Highly stable operation and results
4. NDIR detection of TOC in the ppb to percentage range (can also measure TN b
)
5. Ability to remove excess salt via ash crucible
5

Iso TOC cube
Current Techniques
Preparation off-line
Large sample sizes, complicated methodology, specialised equipment, analysis by dual inlet, slow
EA-IRMS
Concentration by evaporation or lyophilisation, analysis by EA-IRMS
Does not work well when high concentrations of inorganic salt are present
Wet oxidation TOC-IRMS
Using UV or persulfate for oxidation of the sample.
Few samples can be analysed before halide gasses corrode reaction vessel, salt deposition in flow lines, consumption of halogen trap
6

Iso TOC Cube
Elementar have over 30 years of experience in manufacturing TOC analysers
The vario TOC cube is the latest version in the cube format
7

Iso TOC Cube
Features
Integrated 50 position liquid sampler with integrated automated sample feeder
8

Iso TOC Cube
Features
Screwless casing with easy access to 5 sides of the instrument
Simple maintenance with immediate access to all parts
9

Iso TOC Cube
Features
Multiport valve
Halogen trap
Drying tube
Furnace
Syringe pump
Acid reservoir
10

Iso TOC Cube
Ball & Clamp Fittings
Use of ball & clamp fittings throughout the instrument for simple maintenance with no need for tools
11

Iso TOC Cube
Benefits during IRMS
• Iso TOC cube uses direct analysis of TIC & TOC
• Does not use subtraction method (TC - TIC = TOC)
• High temperature oxidation furnace for combustion of C to CO2
• Does not use wet oxidation (persulfate/UV oxidation)
• O2 carrier gas used
• Does not use synthetic air
• Combustion tube containing CuO @ approx 950 °C
• Does not use expensive platinum
• Requires interface for IRMS for coupling to IsoPrime100
12

2
13

Iso TOC Cube
IRMS Interface Introduction
14

Iso TOC Cube
CO2 Column Trapping
15

2
16

Iso TOC Cube
CO2 Column Release to the IRMS
17

• Exchange from O
2 to He carrier gas
• Purge and trap adsorption column for peak focusing (no liquid nitrogen needed)
• reduction furnace to remove interference species and residual oxygen
18

Iso TOC Cube
~1ppm C Precision
13/05/2011 (7.33 to 10.24)
TOC-IRMS Settings
C-concentration ~ 1ppm
Sample volume ~ 3.5ml
CO2 Adsorption by Silica gel
Trap 550 uA
IR bridged (1/16th" Haler)
Peak Ave time N = 285
He Purge = 30s
Sample
CitricAcid1
CitricAcid2
CitricAcid3
CitricAcid4
CitricAcid5
CitricAcid6
CitricAcid7
CitricAcid8
CitricAcid9
CitricAcid10 nA
5.30
4.65
4.60
4.37
4.25
4.48
4.53
4.43
4.38
4.46
Ave
SD
δ 13 C
-18.04
-17.27
-17.23
-17.28
-17.48
-17.15
-17.24
-17.24
-17.24
-17.23
-17.26
0.089
19

Iso TOC Cube
~0.15ppm Water
13/05/2011 (10.41 to 13.15)
TOC-IRMS Settings
C-concentration ~ 0.15ppm
Sample volume ~ 3.5ml
CO2 Adsorption by Silica gel
Trap 550 uA
IR bridged (1/16th" Haler)
Peak Ave time N = 285
He Purge = 30s
Sample
DI water 5
DI water 6
DI water 7
DI water 8
DI water 9
DI water 10 nA δ 13 C
0.35
-33.70
0.36
-34.19
0.32
-34.06
0.37
-34.64
0.33
-34.54
0.32
-34.74
Ave -34.31
SD 0.40
20

Iso TOC Cube
TOC-IRMS Accuracy
10/05/2011 (7.38 to 16.12)
TOC-IRMS Settings
C-concentration ~ 10ppm sample vol ~ 1.5ml
CO2 Adsorption by Silica gel
Trap 200 uA
IR bridged (1/16th" Haler)
Peak Ave time N = 285
He Purge = 30s
Sample
ANU Sucrose 1
ANU Sucrose 2
ANU Sucrose 3
ANU Sucrose 4
Citric Acid 1
Citric Acid 2
Citric Acid 3
Citric Acid 4
RossmSugarA1
RossmSugarA2
RossmSugarA3
RossmSugarA4
Glutamic AcidA1
Glutamic AcidA2
Glutamic AcidA3
Glutamic AcidA4
Glutamic AcidB1
Glutamic AcidB2
Glutamic AcidB3
Glutamic AcidB4
Testsugar1
Testsugar2
Testsugar3
Testsugar4
RossmSugarB1
RossmSugarB2
RossmSugarB3
RossmSugarB4
ANU Sucrose 5
ANU Sucrose 6
ANU Sucrose 7
ANU Sucrose 8
6.29
6.02
6.11
6.01
6.13
5.98
5.98
5.99
5.96
5.96
5.93
5.89
5.88
6.13
6.28
6.16
6.13
6.04
5.95
5.98
5.91
nA
6.33
6.29
6.35
6.44
6.48
6.47
6.4
6.35
6.35
6.18
6.26
-27.98
-25.57
-25.55
-25.56
-25.56
-25.16
-25.18
-25.13
-15.90
-26.19
-26.21
-26.11
-26.21
-27.89
-27.92
-27.95
-25.13
-10.80
-10.57
-10.53
-10.54
δ 13 c
-11.65
-10.72
-10.57
-10.52
-16.18
-16.24
-16.17
-16.10
-15.92
-15.90
-15.94
Ave
-10.55
-16.17
-15.92
-26.18
-27.94
-25.56
-25.15
std dev Actual
0.04
0.06
0.02
0.05
0.04
0.01
0.02
-10.5467
0.02
-10.50
-16.00
-16.30
-26.10
-28.40
-26.00
-25.70
-10.50
21

Iso TOC Cube
TOC-IRMS Accuracy
-20
Experimental δ 13 C
-15 -10 -30 -25 y = 1.0239x + 0.2852
R² = 0.9989
-5
-15
-20
-25
-30
0
0
-5
-10
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Stability (precision) and memory effect
Signal
[nA]
12
12
12
16
12
12
12
12
5
5
5
5
12
55
55
55
55
16
16
55
55
Absolute shift
[‰]
11.14
30.10
38.62
37.70
23.08
37.56
18.43
10.92
30.34
37.79
14.55
23.00
38.87
17.51
15.65
73.07
62.30
15.41
16.10
11.16
5.61
Injection 2,3,4 d 13 C stdev
[‰]
0.06
0.10
0.05
0.09
0.07
0.09
0.10
0.13
0.05
0.03
0.19
0.15
0.02
0.09
0.18
0.27
0.23
0.05
0.13
0.04
0.04
Injection 3,4,5 d 13 C stdev
[‰]
0.04
0.04
0.03
0.04
0.05
0.02
0.05
0.08
0.04
0.04
0.10
0.07
0.02
0.10
0.02
0.14
0.13
0.05
0.02
0.06
0.02
Absolute shifts between 11-39‰
Low C (5-12nA signal)
Very good precision: ≤ 0.20‰ and ≤ 0.1‰ for shift below 30‰
Absolute shifts between 6-73‰
High C (16-55nA signal)
Still very good precision: ≤ 0.20‰
(shift larger than 60‰ ≤ 0.30‰)
With 5 injections all data ≤ 0.10‰
(shift larger than 60‰ ≤ 0.20‰)
23

Accuracy
All data corrected with 2 points calibration curve
Caffeine (IAEA-600) d 13 C
Glucose (IAEA-CH6) d 13 C
-27.77‰
-10.45‰
-60 -50 -40 -30 -20 y = 1.00031x + 0.04485
r 2 = 0.9999
-10 0
0
-10
-20
-30
-40
-50
-60
TOC measured
13
C [‰]
Average difference between measured and target value
0.09‰
Only in 3 over 13 measurements differences ≥ 0.15‰
24

Linearity of the system and concentration range
(data courtesy of Dr. Chiara Cerli – U. Amsterdam)
IRMS signal [nA]
18 27 36 45 55 64 73
-9
-12
-15
-18
-21
-24
-27
-30
-48
-51
0 9
0 20 40 60 80 100 120 140 160
DOC [mgC L-1]
L-tryptophane acetovanillone humic acid benzoic acid urea mixture citric acid melamine caffeine glucose
Between 5-150ppm (5-70nA)
Very good linearity:
≤ 0.03 ‰/nA
Between 1-150ppm (1-70nA)
Very good linearity:
≤ 0.03 ‰/nA except for
L-trypthophane (0.07 ‰/nA) humic acid (0.06 ‰/nA) glucose (0.04 ‰/nA)
25

Real samples
-25.6
-26.0
-26.4
-26.8
-27.2
-27.6
-28.0
-32.4
-32.8
-33.2
0 20
0.5 ml injection, different concentrations
DOM extracted from:
H horizon from Podzol
(std dev 0.02‰)
Forest floor
(std dev 0.15‰)
Peat
(std dev 0.03‰)
Rice
(std dev 0.05‰)
Moss
(std dev 0.17‰)
40 60 80
DOC [mgC L
-1
]
100 120 140 peat forest floor
H podzol moss rice
Measured very well
26

Real samples: concentration vs volume
(data courtesy of Dr. Chiara Cerli – U. Amsterdam) d 13 C d 13 C
Citric acid
Benzoic acid
L-Trypthophane
Acetovanillone
Acetovanillone (fix C)
Urea
Caffeine
Mixture
Humic acid
Humic acid (fix C)
Melamine
Glucose
DOM_Moss
DOM_Moss (fix C)
10-150 mgC L -1 stdev 10-100 mgC L -1 stdev
-28.93
-26.18
-26.34
-19.77
-11.16
nd
-32.81
[‰]
-25.35
-28.92
-11.35
-30.53
-30.58
-50.05
-49.06
[‰]
0.18
0.34
0.31
0.15
0.03
0.17
0.23
0.62
0.30
0.03
0.23
0.21
nd
0.09
[‰]
-25.44
-28.91
-11.47
-30.61
-30.57
-50.13
-49.16
-29.08
-26.21
-26.35
-19.89
-11.24
-32.70
-32.80
0.68
0.35
0.03
0.15
0.19
0.17
0.09
[‰]
0.11
0.40
0.09
0.07
0.03
0.12
0.18
Constant inj vol (0.5ml)
Various C concentrations
(10-150 mg L -1 )
Good std dev:
≤ 0.30 ‰
Constant C injection
(25mgC, ~22nA)
Inj vol 0.08-2.5ml
Very good std dev:
≤ 0.09 ‰
27

Conclusions
Performances very satisfying stable system (large ‰ shift) accurate
Wide range of system linearity (2-80nA <0.03‰/nA) flexibility for handling real samples
Injection volumes (0.05-4ml)
1 nA/µg C
`high throughput, easy to use and maintain
Very interesting tool that widen opportunities for studies in environmental research
28

Federherr E., H.P. Sieper, Lutz Lange, H.J. Kupka, R. Dunsbach, F. Volders
Paul Wheeler, Mike Seed, Will Price, Rob Berstan
Special thanks go out to Dr. Chiara Cerli at the University of Amsterdam
(Institute for Biodiversity and Ecosystem Dynamics) for providing us with additional data.
29

INTRODUCTION
30

IR detector
Drying tube
Nafion
Membrane
Sample vial
Halogen trap
Sparger
Sample
Syringe
Furnace
Condenser
31

STEP ONE
32

33

STEP TWO
34

35

STEP THREE
36

37

STEP FOUR
38

39

STEP FIVE
40

41