ICP2
11
February

By Adem Lewis / in , , , /


welcome to part two in our series of videos on ICP OES, inductively coupled
plasma optical emission spectroscopy. In the
first video looked at the instrument itself and
components that are important to its operation. In this video, will be focusing on the operation of the
instrument itself in terms of collecting data. There are three main objectives: In the
section first we’ll look at how we can prepare the instrument for start-up and then we’ll look at the start-up
procedure itself. Once we have completed that we will
start talking about how we can carry out routine operations on
the ICP spectrometer. In other words, we will look at the
actual procedures for creating a calibration curve,blanking the
instrument, and then of course collecting data. The first thing that needs to be
done with this instrument before we even think about starting it up is to ensure that we have proper
ventilation. So make sure that you turn off the ventilation to the atomic
absorption spectrometer and turn on the ventilation to the ICP
spectrometer this can be done by pulling the levers on the fume hoods such that the levers point straight down for the instrument
that you want to have active ventilation and pointing directly left or
right for the instrument that you do not want
ventilated. Once we have secured proper ventilation for the ICP system the next step is to turn on all the a
appropriate gases For ICP, we will be using two
different types of gas. We will be using argon and
compressed air. Now the argon is going to be supplied
using a large liquid argon tank and as you
can see this tank is much more complicated than the one that you are used to for the AA In other words, the acetylene tank. This
particular tank has several different ports on the top. The only one that we’re going to concern
ourselves with right now is the one that leads to the regulator
on the left hand side. By turning on the green valve connected
to that regulator we will be supplying sufficient argon gas to the instrument.
Once the argon source has been turned on the next step is to make sure that the
compressed air has been turned on. For information on how to turn on
compressed air please see the video on atomic absorption spectroscopy. It is important to note thats both the compressed air and the
argon need to be pressurized within the
parameters that have been set for the ICP instrument.
These parameters can be found on sign on the wall next to the instrument. Once the gases have
been started up and the ventilation has been turned on, the next task for us is to
turn on the actual spectrometer and this is accomplished by turning on
the on switch on the right side of the instrument.
Please note that this switch needs to be clicked over completely. If you push it to gently you will not
turn the instrument on so please make sure that you push the
switch over all the way. And that’s about all that needs to be
done to start the instrument up. With the instrument started, we can now turn
our attention to the software that’s required for running the instrument. On the computer
you will find an icon on the desktop called “win lab”. By
double clicking on the icon you open up the software. Upon starting
the win lab software you’ll see a startup screen as shown in
this image here. There are two boxes that indicate
that the instrument itself has
been completely turned on prior to opening up the software. The
check boxes should show up green. If you get in error message simply close down the software and
restart after the instrument has had enough time to start up completely. At the
completion start-up you will notice that the workspace is opened up onto the computer screen. This
workspace does look very complicated at first glance– there are many different
buttons and many different functions.
Fortunately there’s only a handful of these that we
actually need to use in order to collect data. one of the most important parts here is
going to be the method button s which can be found on the top middle to right hand side of the
computer screen. By clicking on the method button, we can
actually edit the method. In other words, it allows us to select a
metal, wavelength, read delay, and all sorts of different
things like that. The next button I would like to call
your attention to is the plasma button. By pushing this button you’ll gain
control over the start-up of the plasma in the ICP spectrometer. This will also
allow you to monitor the levels of the different gases coming into the instrument. The next box that I would like you to pay
attention to is the manual box. By clicking on this box you open
up an interface that allows you to collect
sample (data) and to insert sample names, blank the
instrument, enter standards; all that the last button we’ll be looking at is the
results button. By clicking on the results button we
open a text-based screen where you’ll find all the data that we
collect during your analysis. As noted earlier by clicking on the
plasma button we bring up the screen that allows us to
control the plasma itself. The screen contains an on-off switch that will turn the plasma on and off– among
many other different types and gauges. Of all the things that are on the screen the
one that is most important (next to the on-off switch) is to control
the peristaltic pumps for sample delivery to
the system. Clicking on the button labeled manual will bring up a window that allows us to enter the identities of our samples, to
run blanks on the instrument, to run samples, and to run standards. Now for the purpose of our classes
we will not be running any standards. We will run our standards as
if they were samples. The reason for this is that the
instrument comes equipped with some really fancy tools that will create a calibration curve
for you and do your calculations for you. But being that this is your first course
using ICP you are responsible for computing your
own calibration curves using Excel. By clicking on the method
button I will bring up a screen that will
allow us to select the method that we want to use for our
particular experiment. Our instrument is already equipped
with several different methods for several different elements. However, if you need to analyze for an element other than the
ones you see here you would simply click on
the new method button. For now you wille just be using the methods
that are found on the instrument already so select the
one that the instructor has indicated for this experiment and
press the OK button to complete the selection up the method. With the method selected, it’s now time to
turn on the plasma. As stated earlie,r this is done by
pressing the virtual “on switch” on your computer
screen in the window that’s brought up by
pressing the plasma control button. You’ll notice that upon pushing that
button the instrument will start undergoing
some different sounds. It is important that’s you do not be alarmed by the
sounds. Also notice that there’s going to be a
considerable delay between the point where you press the
power switch and equipment actually starts up. Again, you should not be alarmed by this.If
you find that the torch does not ignite on the first
try do not be alarmed either. Allow two or three times for the instrument to ignite the torch before consulting with the instructor. You will know that you have successfully
ignited the plasma on the instrument when you
look through the viewing window and see a light green flame like shape inside the viewing area. It is recommended that upon igniting the the plasma for this instrument that you
allow it at least half an hour to an hour warm-up before completing any type of analysis. Once the instrument has warmed up
sufficiently you can press the green manual button to open up the screen that
allows you to control the instrument itself. The first thing you want to do is to
place the sipper straw of the ICP into the blank solution. Typically this will be distilledl water
or distilled water with a little bit of nitric acid in it and you’re gonna press
the analyze blank button. Basically what this does is tell the
instrument that this is what nothing looks like. Now after you blank the instrument you
can then use the analyzed sample button to analyze both your samples and your
standards. I highly recommend that you enter a
sample name for each one of the samples that you
introduce into the instrument to aid you him being able to decipher
which reading belongs to which sample after the analysis has been completed. In the process of analyzing samples you
may notice that the instrument takes a little bit longer
than it typically does to collect the data during an individual replicate for that sample. Typically this
is due to some kind of a problem with the sample introduction system. I in other words the instrument has not
seen an
even intensity being produced by your sample. When this happens you should consult
with your instructor to look for different problems that may
be causing this issue. When the analysis
is complete you can open the results window by
pressing results button on the main workspace. This
will open up a text-based document that will contain all the data and. information about your
experiment The data that is probably most importance to you will be the corrected
intensity the average corrected intensity for your
specific sample. This is the number that you should use as the the value when creating a
calibration curve or when converting intensity to a
concentration. the values on the table can be
printed out or they can be saved to a flash drive.
Either way you can remove the data from this
computer and take it with you so that you can analyze it. I would
also like to point out that the information that’s on your data sheet can also be used to determine whether or not the instrument
is operating properly. For instance you can look at the
magnitude of the values of your samples and if they tend to be very low when you know
that your concentration of analyte is very high, this is a pretty
good indication that the sample introduction system may be
blocked up or possibly you made your samples incorrectly. You may also notice
that you will receive an error message
that says “saturated”, which would be an indication that you’re
concentrations are much too high for the instrument. You may see a great
deal variation within the replicates of a given
solution. This is an indication that there
may be problems with the sample introduction system; or the pump may not be working properly,
there may be a clock et cetera.
Well that pretty much wraps up
everything that you need to know to start up the ICP instrument
and to run a very basic analysis. There are some other subtle nuances and important
details that will make your usage at this
instrument more effective or efficient. As always I recommend that you take the time to
meet with your instructor to discuss some of the finer details of
this instrument and of course to make sure
that you take the time to practice on this instrument as well so you will be
successful in your practical exams and your future career. Thank you for taking the time to watch
this video


2 thoughts on “ICP2

  1. Watching a few videos I can see your art and skills saving time, not only for students, but for professionals in labs. Great job.For limited personnel labs the same people deals with hundreds of different devices and processes. Thanks to your video material they can quickly recall the most important steps they have to fallow saving time and money. Even a task seemingly simple is simple base on its "simplicity foundation"
    I do thank you very much for your work
    Wesley

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