Measure. Analyze. Learn.
The Vernier Mini GC Plus is an instrument for
separating, analyzing, and identifying substances,
contained in a volatile liquid, or a gaseous sample.
The Mini GC Plus can detect and distinguish between
families of compounds such as alcohol, ketones,
esters, and halogenated alkanes.
A complete list of compounds that can be used
in the Mini GC Plus is available
under appendix A in the user guide.
The column of the Mini GC Plus can be operated at
temperatures ranging from 30 degrees to 160 degrees Celsius.
The MEMS chip sensor can be operated at 2 levels of sensitivity,
allowing for a greater range of compounds
and injection volumes to be used.
For personal protection we recommend
open reagent containers be handled in a hood,
or a well ventilated area,
and appropriate safety equipment be used.
The Mini GC Plus is a USB device, and can be used with
a computer running Logger Pro or a LabQuest.
This session will go over instructions for collecting data
using LabQuest 2 and the Mini GC Plus,
along with Peak Integration Function
available under the analyze menu.
Make sure LabQuest 2 has been updated to 2.1 or newer.
This free update is available on our website.
You will need a 1 microliter syringe, a vial of ethanol or acetone
to rinse your syringe, and your sample.
A Hamilton 1 ÁL syringe is included with the Mini GC Plus.
This rinse vial contains acetone.
The sample is a 1 to 1 mixture of ethanol and 2-butanone.
Prepare the Mini GC Plus for data collection.
Connect the Mini GC Plus to an electrical outlet.
Turn on the Mini GC using the on/off switch,
located on the left side.
Connect the USB cable to the USB Port of LabQuest.
LabQuest will auto ID the Mini GC Plus.
Select "File" - "New" to ensure software settings
are set to default values.
Tap on collect to bring up the "Temperature-Pressure Profile".
Depending on your sample, you may need to modify
these parameters to obtain good separation.
For this sample mixture, change the pressure to 4 kPa.
Data collection will end after 20 minutes.
Make sure the duration of the run is long enough to
ensure all the compounds have passed through the column.
Select "Done" to initiate Mini GC warm-up.
A new message will appear, "Do not inject until GC is ready.",
and the LED on the Mini GC Plus will be red.
The Mini GC will take a few minutes to warm up and stabilize.
While waiting, flush your syringe with the sample to be tested.
The glass syringe is fragile.
Be careful not to bend the needle, or bend the plunger.
Never pull the plunger back more than 50% of the total volume.
Submerge the tip of the needle into
the vial containing the sample.
Pull back the plunger to fill the barrel about 1/3 full.
Expel the liquid onto a paper towel.
Repeat this process 2 more times.
Then collect a volume of the sample for injection.
Submerge the needle into the vial containing your sample.
Pull your plunger back draw up approximately .2 ÁL of liquid.
After collecting your sample,
gently wipe your needle from barrel to tip.
When the Mini GC Plus has reached
the correct start temperature and pressure
the message reads, "Inject and select Collect simultaneously.",
and the LED on the Mini GC Plus is green.
Hold the syringe with one hand,
steady the needle with the other hand,
supporting the needle guard and the lower part of the needle
with two fingers to prevent the possible bending of the needle.
Insert the needle into the injection port until
the needle stop is fully seated.
If the needle sticks, rotate it slightly while inserting.
Do not move the plunger yet.
With the help of my lab partner, I will simultaneously
depress the syringe plunger and select "Collect"
to begin data collection.
Pull the needle out of the collection port immediately.
While the data collection proceeds,
thoroughly clean the syringe and needle with acetone.
It may take more than 3 flushes to feel
the syringe plunger move smoothly again,
which is your indicator that the syringe and needle
are both suitably clean.
To identify the retention time for our peak,
tap on the graph on the screen.
This will bring up the examine line.
Move the examine line to the top of the peak
by tapping on the screen.
To fine-tune the location, use the nudge tools
located at the bottom of the graph.
The time displayed represent the retention time
for the selected peak.
Another analysis tool is peak integration.
Tap on "Analyze",
choose "Advanced",
choose "Peak Integration"
then "Signal".
Select and integrate the peak, drag across the graph
from a little before the peak to a point far enough to the right
so that the entire peak is selected.
Choose "Add".
Enter the name of the compound if known.
Tap twice on Peak 1, and type in "ethanol".
Choose "Done".
Repeat these steps until all peaks have been analyzed.
For the second peak, typing in "2-butanone".
When you're complete, press "OK".
This will bring up the plot details,
then select "OK" to return to your graph.
For additional information including maintenance,
troubleshooting, and product specification
please refer to the user guide,
or visit our website.