Contents
hide
Gas chromatography–mass spectrometry Calibration Procedure
|
Check
parameters
|
Acceptance
criteria
|
|
Mass Sensitivity
|
S/N Ratio
> 60:1
|
|
Repeatability-RT
GC-MS/MS
FID &
ECD
|
% RSD MAX
0.5 %
2.0 %
|
|
Repeatability-Area
GC-MS/MS FID & ECD
|
% RSD MAX
5 %
3 %
|
|
Detector linearity
|
R² ≥ 0.99
|
|
Split Ratio
|
R² ≥ 0.99
|
|
Carry-over
|
Height should be less than 0.4% |
Sensitivity (GC-MS)
- Check the Autotune, Self-calibration and save the calibration details.
- Prepare the standard octafluoronaphthalene (OFN) in the concentration of 1 pg/ul in iso octane in suitable sample vial.
- Inject octafluoronaphthalene and run the GCMS.
- Check the signal noise ratio and mass spectrum of the OFN.
Acceptance
EI Sim Or MRM: S/N> 60 octafluoronaphthalene for 10 ppb molecular ion at m/z 272.
Repeatability
|
Instrument
|
Details
|
Acceptance
criteria
|
|
GC-MS
|
Lindane is
taken for calibration of Gc-Ms. Other Gc compounds of known purity can also be selected as reference material.
Prepare 100 μg
/ml from the stock solution.
Inject 5
replicates and calculates the % RSD for the Retention time and Area.
|
% RSD for Retention time should be ≤ 0.5 %
% RSD for Area Should be ≤ 0.5 %
|
|
GC-FID
|
Prepare 10%
ethanol in water. Stock volume and final volume can be changed depending on the availability of micro pipette and volumetric flask. Inject 5 replicates
and calculates the % RSD for the Retention time and Area.
|
% RSD for Retention time should be ≤ 2 %
% RSD for Area Should be ≤ 3 %
|
|
GC-ECD
|
Prepare 100 μg/ml
of lindane in ethyl acetate and Inject 5 replicates and calculates the % RSD for the Retention time and Area.
|
% RSD for Retention time should be ≤ 2 %
% RSD for Area Should be ≤ 3 %
|
Detector Linearity
|
Instrument
|
Linearity
|
|
GC-MS
|
Prepare 20, 40, 60, 80, 100 ng/ml lindane Calibration
Solution and inject. Plot linearity graph between concentration on the X axis and Area on the Y axis.
|
|
GC-FID
|
Prepare 0.5, 1, 5, 10, 25, 50 % ethanol in water and inject
in GC-FID. Plot linearity graph between concentration on the X axis and Area on the Y axis.
|
|
GC-ECD
|
Prepare 20, 40, 60, 80, 100 ng/ml lindane in ethyl
acetate and inject in GC-ECD. Plot a linearity graph between concentration on the X axis and Area on the Y axis.
|
Acceptance criteria
The correlation coefficient r2 obtained from the
linearity graph for different levels should not be less than 0.99
linearity graph for different levels should not be less than 0.99
Split Ratio (Gc-Ms)
Inject same concentration of standard soln at
different split ratio as 1:10, 1:50, 1:100 and record the chromatogram for each
split ratio. Plot a linearity graph between ratio on the X-axis and area on the
Y-axis.
different split ratio as 1:10, 1:50, 1:100 and record the chromatogram for each
split ratio. Plot a linearity graph between ratio on the X-axis and area on the
Y-axis.
Acceptance criteria
The correlation coefficient r2 obtained from the
linearity graph for split ratio should not be less than 0.99
linearity graph for split ratio should not be less than 0.99
Carry Over (GC-MSMS, GC-MS, GC-FID, GC-ECD and Head Space)
Keep the vials Containing solvent and analyte in solvent in
the following order.
the following order.
|
Vial No. |
Position |
Sample |
|
1. |
10 |
Solvent |
|
2. |
11 |
Std. in |
|
3. |
12 |
Solvent |
Calculate the percentage of carry over as following
Carry Over (%) = HCo *100 / Hi
Where
HCo – peak
height of analyte from vial 12.
height of analyte from vial 12.
Hi – peak
height of analyte from vial 11.
height of analyte from vial 11.
Acceptance criteria
Height should be less than 0.4%
Head Space
Inject 1 mg/l hexane in oil in 5 replicates and calculate
the % RSD for the Retention time and Area.
the % RSD for the Retention time and Area.
Acceptance criteria
% RSD for Retention
time should be ≤ 0.5 %
time should be ≤ 0.5 %
% RSD for Area Should be ≤
0.5 %
0.5 %
RSD Formula
RSD = STDED * 100 / Avg
Frequency- Every Six Month
Maintenance
-
Check the gas connection, moisture trap condition column connections, any leak in the helium cylinder and change the septa if damaged.
-
Run the column conditioning at the end of the sequence.
-
After every 50-60 injections the septas are needs to be changed.
-
Do bake out the system whenever the vacuum is put down and the moisture is high.
-
Clean the liner in every hundred injections depending on the sample matrix analysed.
-
Change the wash solvent in the vial daily. Before start of analysis.
-
Do a frequent test of gas leakage to avoid any hazard.
-
Read More….
Hmm it looks like your blog ate my first comment (it was super long) so I guess
I’ll just sum it up what I submitted and say, I’m thoroughly enjoying your blog.
I as well am an aspiring blog blogger but
I’m still new to everything. Do you have any tips for inexperienced blog writers?
I’d genuinely appreciate it.
Outstanding story there. What occurred after?
Thanks!
What’s up to all, how is all, I think every one is getting more
from this web page, and your views are fastidious designed for new users.
Hey there superb blog! Does running a blog like this take a lot of work?
I have very little expertise in programming however I had been hoping to start my own blog in the near future.
Anyways, if you have any ideas or techniques for new blog owners please
share. I know this is off subject however I just needed to ask.
Many thanks!
It is the best time to make some plans for the future and it’s time
to be happy. I have read this post and if I could I want
to suggest you few interesting things or suggestions.
Perhaps you can write next articles referring to this article.
I desire to read even more things about it!
Thanks very nice blog!
We are a group of volunteers and opening a new scheme in our
community. Your web site offered us with valuable info to work on. You’ve done an impressive job and our entire community will
be grateful to you.
Wonderful goods from you, man. I have understand your stuff previous to and you are just extremely excellent.
I actually like what you’ve acquired here, really like what you’re stating and
the way in which you say it. You make it enjoyable and you still take care of to keep it smart.
I can’t wait to read much more from you. This is actually a great web site.
I like this web site very much so much fantastic info .