Agilent 7697A Headspace Sampler
With 7890B GC and 5977A MSD
Mike Szelewski
Agilent Technologies
Wilmington,DE
February 14, 2013
January 8, 2013
Agilent Confidential
1
VOA Analysis with a
Headspace Sampler
GC/MSD System
Highlights for Headspace-GC/MS
7697A HSS - 7890B GC / 5977A MSD
1. MassHunter for Acquisition - it’s easy
2. MassHunter for Data Analysis - many features
3. Sensitivity (S/N) - better with the new extractor lens
4. LOD (IDL) as measured by replicate injections - meets your needs
5. Linearity as measured by R2 - near perfect
2
MassHunter 5977A Acquisition
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1. Existing MSD Chemstation acquisition methods for SIM are easily converted to
MassHunter methods for 5977A
2. Simply load an existing 7890A/5975C method directly into MassHunter
3. SIM groups, SIM ions, and times are all preserved
4. Modification of SIM ions/groups is much easier than in MSD Chemstation
Note:
Acquisition parameters do not match the existing VOAs Headspace Analyzer. The
column flow chosen here matches that used by many customers.
MassHunter 5977A Acquisition, after directly loading a
7890/5975 method
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All of the ions,
groups and
times loaded
without error
Page 5
Ramp 'C/min 'C Hold min
Initial 30 0.3
Ramp 1 10 185 0.0
Runtime 15.8 min
MSD Agilent 5977
Inlet MMI
Solvent Delay 0 min
Temp 150 'C
SIM Ions 3-15 ions/group
Mode Hot Split
Dwell 20-100 msec
Flow 1.0
# Groups 19
Quad Temp 180 'C
Source Temp 280 'C
Transfer Line 190 'C
Standards: methanol dilutions of commercial
standards from UltraScience. 2000 ppm stock
solutions containing 60 compounds and/or 6
gases diluted into methanol containing 2 ppm
of 3 ISTDs. Methanol spikes of 15 uL into 15
mL water for headspace use
Column DB-5MSUI part # (122-5533UI)
Injection volume 1 mL loop
Outlet Pressure Vacuum
30m x 0.25 mm id x 1.0 um film
Tune etune.u Gain = 5
Postrun none
Acquisition Mode SIM
Split Ratio 40:1
TID On
Method Parameters for 7697-7890/5977 VOAs
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HS oven temp 70 'C
Equilibration 10 min
Liner 1 mm id, straight, no packing Extractor lens 3 mm
Equilibration 10 min
Sample size 15 mL in 20 mL vial
Alternate
column
DB-624 part # (122-1334)
20m x 0.18 mm id x 1.4 um film
Alternate column results were almost identical to the initial
column however peak shape was slightly worse for
the earliest eluters
SIM-TIC of VOA std, 53 compounds at 50ppt,
3 ISTDs at 2ppb and 6 gases at 100 ppt.
7697-7890/5977 Headspace-GC/MSD
Vinyl chloride
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MassHunter 5977 Data Analysis - Existing MSD Chemstation
data analyses methods for are easily converted to MassHunter
methods. qdb.mth is the calibration database , ESTD in this case
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Input the path to the
existing method you
want to convert
Use this default name
for the converted
quant method
Click this button
and WHAM !
you get this
MassHunter 5977A Data Analysis - converted from
MSD Chemstation, then calibrated.
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The Scan
column had to
be changed to
SIM, the only
needed change
Mass Hunter 5977 Data Analysis - Benzene calibration from
50-20,000 ppt (0.05-20 ppb)
9
5 cal levels
Benzene
overlay with
TIC
50 ppt
Benzene
Cal curve
and ISTDS
Sensitivity Improvement up to 2.7x using the 5977A
Extractor Lens for Headspace Volatiles*
1. Signal-to-Noise varies from no improvement to 2.7x better, comparing runs with
and without using the extractor lens
2. Vinyl chloride - no S/N increase, signal and significant noise both have higher
amplitude using the extractor lens
3. Toluene - 2.7x S/N increase, very low noise background
4. S/N improvement can not be predicted by ion nor retention time
5. All ions show higher signal using the extractor lens compared to not using it
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* 4 runs were made with each tune file. S/N was calculated for 14 compounds
in each run, then averaged
Limit Of Detection (LOD) based on 7 replicate
analysis of a 200 ppt standard in water
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2013
2009 EC UK-EA 2009 EC
Named 5977 bid spec Reporting
Compounds LOD LOD Level
Vinyl Chloride 60 100 500
1,2-Dichloroethane 23 100 3000
Benzene 20 100 1000
Trichloroethene 21 100 10000
Tetrachloroethene 17 100 10000
LOD is based on area repeatability and not on S/N
All values are parts-per-trillion
Desired LOD is typically 5-10x less than reporting level
40:1 split delivers less water on column, good peak shape
and good reproducibility
Vinyl chloride lowest calibration level, 100 ppt
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*1.889 min. Vinyl Chloride 0.1074 ppb
This is also the
requested LOD
level for the
UK-EA bid
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
1.1
1.2
1.8 1.9 2 2.1
Linearity reported as R2. 5 level calibration from 50
ppt to 20,000 ppt (0.05-20 ppb), ISTD
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50-20,000
Tgt ppt
R.T. Ion R2
Vinyl Chloride 1.91 62 0.9999
1,2-Dichloroethane 4.81 62 1.0000
Benzene 4.99 78 1.0000
Trichloroethene 5.67 95 0.9999
Tetrachloroethene 7.83 166 1.0000
Vinyl chloride calibration levels are 2x higher
MassHunter 5977A Data Analysis - Vinyl chloride calibration
from 100-40,000 ppt (0.1-40 ppb)
14
5 cal levels
Vinyl
chloride
overlay with
TIC
100 ppt
Vinyl chloride
Cal curve and
ISTDS
Summary for Headspace-GC/MSD
7697A-7890B/5977A
1. MassHunter Acquisition - all MSD information on one page. If you can run MSD
Chemstation, you can easily run this. GC and Headspace screens the same as
before.
2. MassHunter for Data Analysis - very versatile for target compound quantitation.
Batch view speeds data review
3. Sensitivity (S/N) - up to 2.7x better with the new extractor lens compared to the
old drawout lens
4. LOD (IDL) as measured by replicate injections - all less than 100 ppt (0.1 ppb) for
60 common drinking water volatiles
5. Linearity as measured by R2 - 0.9996 - 1.0000 across a calibration range of 50 -
20,000 ppt
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