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[ Music ]
>> Good afternoon.
Today I will be presenting planar solid phase
microextraction ion mobility spectrometry.
And I will be performing a demonstration
of this technology.
First of all, the trace explosive detector
that we'll be using for the demonstration is the mobile
trace by Morpho Detection.
And prior to conducting any experiments for the day,
the protocol is to always perform a calibration
and a verification at least once daily.
So first of all we will obtain hard calibration traps.
[ Silence ]
>> And you can tell these -- the difference between these traps
by the letter that's on them.
So this is c for calibration.
So we go to the instrument screen and select cal,
which stands for calibrate.
Now the instrument is requesting
that I insert the cal trap and press trigger.
I am pressing trigger on the screen,
and the instrument is sampling.
A sample takes about 8 seconds.
[ Silence ]
>> So the instrument has calibrated itself,
and it provides you with a data file number.
And I just press OK.
And I don't have any notes, but it is an option.
Press Enter, and the screen tells me
that the negative calibrant has been calibrated
to a certain position, and so has the positive calibrant.
So this means that this instrument has now been set
and calibrated.
[ Silence ]
>> And we see that it's telling us
that contraband has been detected.
So these calibration traps contain TNT and ***,
and we see two peaks for these -- TNT in the negative mode
and *** in the positive mode.
So we remove the calibration trap and discard.
[ Silence ]
>> Now that the instrument has detected these compounds,
we normally do a clear function in order to help clear
out the analyte that was detected.
So on the touch screen we press Clear.
[ Silence ]
>> Now the instrument requests that I insert a clean trap.
So you take a trap from the sample traps
multi-purpose canister.
And this trap has no letter on it, it's just the hole.
Okay. So I insert the trap into the desorber and press Trigger.
And we see a green screen, and it says that it --
there is no alarm, and the instrument is ready.
So we discard this trap, and now we're ready
to perform a verification.
[ Silence ]
>> So you select a verification trap
from the canister labeled multi-purpose
verification traps.
[ Silence ]
>> And these traps have a v on them.
So prior to inserting the verification trap, I need to go
into the -- to the menu,
and select Verify on the touch screen.
And now the instrument requests
that I insert a verification trap and press Trigger.
[ Silence ]
>> Okay. The instrument indicates
that verification is successful.
And again, these verification traps contain two additional
compounds in order to verify their drift time position.
[ Silence ]
>> So now that we have a hit, we'll press Clear.
[ Silence ]
>> And now again the instrument is requesting
that I insert a clean trap.
And again, I will take one from the sample trap canister.
[ Silence ]
>> Press Trigger.
[ Silence ]
>> Okay. So no alarm ready is what comes up in a green screen,
and that means that we are ready
to analyze our samples for the day.
So today we will be showing you how to conduct PSPME sampling,
and couple that with ion mobility spectrometry.
So we will prepare a can to create a closed environment,
completely sealed, for us to conduct static sampling
with the piece PSPME device.
So our setup is as follows.
We have a baked quart-size can, we use a binder clip
to attach the planar solid phase microextraction device to it,
and we're using unwaxed, unflavored floss.
And we're attaching this to the can with scientific tape.
Okay. So the solution that we will be extracting
from is a spike of 240 ppm TNT and acetonitrile.
I will take 10 microliters of the solution,
and this corresponds to a total mass deposited
into the can of 2.4 micrograms.
But prior to that, we have to ensure
that our planar solid phase microextraction device is blank
and ready to accept our sample.
So this is a planar solid phase microextraction device.
And I will insert it into the instrument's desorber,
and press Trigger.
I obtain the green screen, and it says that there's no alarm
and the instrument is ready.
So the instrument provides you with a filename,
and you can record that, just press OK.
I don't have any notes to enter, so you press OK.
Okay. So now that I know that my blank --
my PSPME piece device is blank, I can introduce it into the can.
But I will set it aside for now.
[ Silence ]
>> Actually, no.
I will remove the lid from the can,
and set up the PSPME device within.
[ Silence ]
>> So I attach the PSPME device
to the binder clip -- with the binder clip.
And the device is suspended into the can --
the head space of the can.
So I will take 10 micro liters of this solution
and deposit it into the quart can.
[ Silence ]
>> Okay.
[ Silence ]
>> Now the can will be sealed with this hammer.
[ Hammering ]
>> An extraction will be performed for 15 minutes.
So during this 15-minute time span, the PSPME
[ inaudible ]
device is allowed to come into contact with the head space
of the TNT that we deposited.
Again, it is important to remember
that we deposited a very minute amount of TNT into this can,
and this device will be used
to absorb the vapors that are emitted.
And following the 15-minute extraction period,
we will introduce the PSMPE device directly
into the instrument, and we will obtain an alert for TNT.
Okay. So we will discard this.
Now we also want to ensure that the vessels
that we're performing these extractions in are blank.
So we have a baked -- a baked can
that contains no analyte inside.
[ Silence ]
>> Okay. So we will sample this blank can just to determine
that there is no extraneous compounds that we are detecting
by ion mobility spectrometry.
But again, whenever we perform a extraction with PSPMS,
we have to ensure that we first obtain a blank with the IMS.
So again, we're going to insert the trap --
or the PSPME device into the desorber of the instrument,
and we will press Trigger.
[ Silence ]
>> Okay. There is no alarm, so we are ready to go.
[ Silence ]
>> So I've removed the PSPME device from the desorber,
and now I will introduce it into our air sampler, as so.
Okay. Our PSPME device is in place,
and I will sample this can for 30 seconds dynamically.
[ Silence ]
[ Air Sampler ]
>> Okay. Now that we have performed this dynamic
extraction with the planar solid phase microextraction device,
we will remove it from the air sampler, and place it
into the instrument's desorber.
And again, we press Trigger.
And now the instrument is sampling.
Okay. So we obtain again, the green screen,
and there's no alarm, and the instrument is ready to go --
meaning that there were no compounds in the blank can
that were extracted or detected
by the ion mobility spectrometer.
[ Silence ]
>> Okay.
[ Silence ]
>> Okay. Our next sample is a smokeless powder --
a small amount, only 100 milligrams.
And this has been sealed inside the can since 7 this morning.
So it's been sealed for about 6 hours.
But prior to performing this extraction, again,
we need to ensure that our PSPME device is blank, as indicated
by our instrument response.
So again, we take our device, introduce it
into the instrument's desorber, and press Trigger.
[ Silence ]
>> We have no alarm, so we can proceed
with sampling and extraction.
[ Silence ]
>> Again, I'll place a PSPME device into the air sampler.
I'll set my timer for 30-second extraction.
[ Beeps ]
>> Okay. I will open the can up.
[ Silence ]
[ Air Sampler ]
[ Silence ]
>> Now that our dynamic extraction is over,
I will introduce it into the desorber, and press Trigger.
Okay. So we see that explosives are detected
from this small sample in as little
as 30 seconds of extraction.
So the instrument provides us
with an alarm data file, and it's alm01131.
So we just hit OK.
I -- again, I don't have any notes to enter.
And the instrument informs us that DNT has been detected,
with a drift time of 5.608 seconds.
So in as little as 30 seconds from a very small quantity
of the smokeless powder H322, we were able
to extract sufficient quantity to produce an alarm by IMS.
So the whole process took under 40 seconds.
[ Silence ]
>> It is important to note
that these pre-concentration devices have very
large capacity.
So even though we have performed one desorption,
we still may have some compounds remaining.
So in order to check for this, we will desorb the device again.
[ Silence ]
>> Again, I introduced it into the desorber, and press Trigger.
[ Silence ]
>> Again, there are still more explosives
that are coming off of this device.
[ Silence ]
>> And this shows how much was in fact extracted
by the PSPME device, again, in as little as 30 seconds.
[ Silence ]
>> So again, I will desorb it one more time.
[ Silence ]
>> And again, we are detecting explosives.
Okay. Okay, now that we have desorbed the PSPMS devices a few
times, because it did collect much of our analyte,
we're going to remove it from the system, and the IMS says
that there's no alarm, and it's ready to go.
Now the reason that you would want
to desorb it several times is
because in fact these devices are reusable.
So if you wanted to move on to another sample,
and you had extracted a large amount of your analyte,
you would want to clear it out and certify
that you do not have any analyte remaining
on your PSPME device prior to moving
on to collecting another sample.
So now our spike of TNT within the can has --
the PSPME device has been in contact
with the head space produced from this very tiny amount
of TNT that is within this can.
So because TNT is semi-volatile, there are vapors available
to be extracted by the PSPME device.
So once your extraction period is over,
you open the paint can as so --
[ Silence ]
>> -- with your tweezers.
You remove the device from the binder clips,
introduce it into the desorber --
[ Silence ]
>> -- and press Trigger.
Okay. And as expected, we have absorbed TNT on this device,
and we obtained an alarm.
[ Silence ]
>> And we obtained TNT at a drift time
of 6.076 milliseconds.
And as is usual, you would want to desorb this device again
to ensure that it is blank.
[ Silence ]
>> And again, we hit on TNT once more.
[ Silence ]
>> Okay. Now we're cleaning out the system,
so it's requesting me to insert a clean trap.
[ Silence ]
>> Okay. No alarm, and we're ready to go.
So now we -- we have already spiked within a can
and sampled statically, we have dynamically sampled a blank can,
and we have also dynamically sampled a very small amount
of smokeless powder within a can.
So our last demonstration is going to be
with the smokeless powder red dot,
and we will perform a static extraction
for only five minutes.
And we will be sampling from the head space
of 100 milligrams of sample.
But before we present the PSPME into the extraction --
into the vessel, we have to ensure that it is blank.
So face it into the desorber and press Trigger.
And the instrument is green -- provides a green screen,
and it says that there is no alarm, and we're ready to go.
[ Silence ]
>> So this small amount
of red dot smokeless powder has been sealed within this can.
So I will open it up, simply
to introduce the PSPME device within.
[ Silence ]
>> And we seal the can with the mallet.
[ Hammering ]
>> And we have our timer set for 5 minutes.
So in 5 minutes we will remove the extraction device,
and introduce it again into the desorber, and press Trigger.
Okay. So our 5-minute extraction period is up.
We will open the can,
which contains 100 milligrams of red dot.
Remove the PSPMS device from the binder clip,
and introduce it into the desorber.
[ Silence ]
>> And I press Trigger.
Okay. And we detect explosives --
the red screen comes up on the instrument.
And we detect the compound Nitro.
[ Silence ]
>> So again, we're going
to desorb the PSPME device again, press Trigger.
Okay. And again, explosives were detected.
This is evidence that the PSPME device collected a large amount
of this Nitro compound from a short 5-minute extraction
from a small amount of smokeless powders.
We're going to clear the instrument.
[ Silence ]
>> I'm inserting a clean trap, and pressing Trigger.
[ Silence ]
>> Okay. There's no alarm, and we're ready to go.