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VOA Analysis with a Headspace Sampler GC/MSD System · Tgt ppt R.T. Ion R2 Vinyl Chloride 1.91 62...

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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
Transcript

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

3

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

4

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

5

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

6

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

7

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.

8

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

10

* 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

11

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

12

*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

13

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

15


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