 channel so good morning good afternoon good evening so whatever time you are watching this video welcome back to my channel so this is drummer Adams once again and I just want to greet everyone hello and I hope that everyone is really doing well today so I hope that you will be enjoying your time your opportunity to learn something new today and I will not be holding you too much long and we will be going straight to our first this question so it's all about your atomic absorption spectrophotometry so your atomic absorption spectrophotometry is a very important instrumentation and clinical chemistry so let's dig in so for this discussion we will be talking about your atomic absorption spectrophotometry and the different components the basic components with regards to your AAS so before we talk about your spectrophotometry and if you haven't watched the video or the discussion regarding spectrophotometry I will be giving you the link on the description box and also somewhere here in your screen it will just pop out so let's dig in so first and foremost what is atomic absorption spectrophotometry so your AAS is actually used to measure concentration by detecting the absorption of electromagnetic radiation by atoms rather than molecules yes what you heard was right what we are talking about now is no longer molecules that is very much the respect in the job of your spectrophotometry now what we are measuring is the absorption of your atoms so we are talking about atoms so now I just want you to differentiate those two because AAS and your spectrophotometry are two different instrumentation so talking about your atoms since we are talking about atoms so the usual things that we measure using your AAS are these elements usually it's your aluminum your calcium your copper your lead your magnesium your lithium in your zinc as you can see most of these things are actually part of your electrolyte some are your trace elements and some are actually your your your heavy metals or your toxic elements that are usually seen in your patients so some you can see them normally in a patient and some you can see them if there is a lead poisoning or plumbism okay so talking now about your atomic absorption spectrophotometry your your AAS is actually 100 times more sensitive than your FES and if you're asking what is FES that is flame emission spectrometry so FES is somehow a very insensitive and non-specific method that's why we are actually using AAS more than your FES so AAS your atomic absorption spectrophotometry again is 100 times more sensitive than your FES so talking about the absorption of your atoms maybe you're asking how can we now determine the concentration of a particular atom the concentration of a particular analyte or element using your AAS so the amount of light absorbed is actually proportional directly proportional to the concentration of your analyte okay so it's very important for us to realize that very much similar to your spectrophotometry it's also directly proportional to the concentration okay so how does your atomic absorption spectrophotometry works okay so here's the thing what we have are actually molly what we have are actually atoms on their ground state so usually what we found what we can actually collect from our patient are actually samples or analytes and eventually those are only on its ground state okay so they are on its ground state or in their neutral state so what will happen is that they will now be excited okay they will now be undergoing excitation whereby they will be at their excited state and then as you all know as you all know when you are in and when you are on an excited state you will be shifting back to your ground state okay and that was and that what's happened to your atoms as well they will be returning from excited state to their ground state and in that in that process they will now be emitting light okay they will now be emitting light so at the moment that your excited atom is returning back to its ground state the the process is actually through emitting a particular light okay through emitting a particular light so again your excited atoms when they return to their ground state they will start emitting light of the same energy as it absorbs so the amount of energy the type of energy the wavelength of energy that your atom absorbs will be the same amount of light when it comes to wavelength and energy that it will be emitting so I hope that's clear so I just want to go back again and explain that when you are doing atomic absorption spectrophotometry what we have are atoms on its ground state so for us to be able to measure them we will be under we will be exposing them to a particular energy for them to be excited and from excited they will actually be returning to their ground state okay they will be returning to their ground state and in that process they will now be emitting light from that atom okay so I hope that is clear so this is actually the normal the simplest format or representation of the atomic absorption spectrophotometry instrumentation what we have here are actually your light source we also have your chopper you also have your nebulizer your atomizer all the same all all on the same side and then you have your monochromator you have your photodetector and then you also have your readout device so let's go on one by one the first one is of course your light source so what does your light source do so your light source first and foremost is of course the source of your incident light so in a as we actually have two types of light source the first one is actually your electrode less discharge lamp in your hallo cathode lamp okay so let me first explain what is your your electrode less discharge lamp in your hallo cathode lamp so your electrode less discharge lamp is consists of a bulb containing or filled with your argon and the element to be tested so it actually uses radio frequency generator to excite to excite the element on the other hand we also have your hallo cathode lamp what does your hallo cathode lamp do so it actually is consists of an evacuated gas type chamber containing an anode as a lindrical cathode and an inert gas usually argon as well in your helium so it actually is separated it's it actually requires a separate lamp for each metal okay so if you're measuring a particular element take for example it's your your aluminum a different lump it's required for aluminum a different lump it's required for your copper zinc so on and so forth and maybe you're asking how does your hallo cathode lamp produces light how does your electrode less discharge lamp produces produces light i hope you're actually um have do you actually have your bishop with you on your side so your hallo cathode lamp let me go first to your hallo cathode lamp so your hallo cathode lamp produces light this way so remember that within the chamber you have your helium and your argon okay now we also have your cathode and your anode so what will happen inside the gas type chamber is that this helium and argon will now be attracted the ions will be attracted to the cathode so the moment that they are being attracted to the cathode they will now be bumping into metals within the gas type chamber and if that happens the bumping of those ions into those metal will cause its excitation okay and again when an when an ion is excited as it returns back to its grand state it will now be releasing your light and that is how your cathode hallo cathode lamp produces light it actually attracts first the ion to it to the cathode bumping into the chain bumping into the metals and then eventually those ions are excited and eventually they will be returning to its ground state producing the light okay on the other hand we also have your electrode less discharge lamp the manner is actually very much similar to your hallo cathode lamp the only difference that the only difference between the two is that it doesn't have your cathode or your anode in your electrode this discharge lamp what we have are actually your radio frequency generator so very much similar to your hallo cathode lamp we also have your ions in the form of your argon so your argon are being excited how through your radio frequency generator so the moment that again your argon is excited it will return back to its ground state now emitting your light so that is how your aas light source produces your light again we have two types your electrode less discharge lamp and your hallo cathode lamp i hope the my explanation was clear so let's move on to the next part which is your beam chopper as you can see your beam chopper is one unique feature of your atomic absorption spectrophotometry and i want you to take note of this one very much um i want you to take note of this very because this is very much important okay so your beam chopper what does it do it actually modulates the the hallo cathode light beam so isn't it that allied actually when when allied is being when your lighters is producing light it's actually producing a light that is consistent when it comes to its intensity so what does your beam chopper does it actually produces pulses of light like what you are seeing in the gif that i provided below so in this case the beam the beam chopper now will cause will cause the system to have pulses of light okay pulses of light and um i just want you to hold on when it comes to the beam chopper because as we go along i will be explaining to you what is the importance of your beam chopper so that is what your beam chopper does again it modulates the hallo cathode light beam and it actually produces pulses of light so like a christmas light like this one and also this one so later on i'll be explaining why is it very much important so after your your beam chopper we go now to your nebulizer okay we go now to your nebulizer and this is again very important because again going back to the definition of aas we are no longer measuring molecules but atoms so how do we do that that is through the help of your nebulizer and later on by your flame or your atomizer so let's move on to your nebulizer your nebulizer its main goal is actually to deliver a fine spray of the sample containing your metallic ion into your flame or your cylinder or in a nutshell we can call it your atomizer okay we can simply call this one your we can simply we can simply call that your atomizer so when it comes to your your your your nebulizer it actually delivers your sample into your into your flame or your cylinder so maybe you're asking what i why do we have a flame and why do we have a cylinder okay why do you have a flame and why do you have a cylinder so here's here comes now your atomizer so as you can see you cannot see a quvet or a sample cell here why simply because your flame or your burner or your graph your your graphite furnace is the sample cell of the instrument itself okay so with the lever from the nebulizer we deliver the sample going to your flame or going to your cylinder which is in turn your atomizer and at this very same time it is also the sample cell when i say sample cell it's the one that holds the sample while it is being measured so what does your atomizer does by the way so your atomizer dissociates the solution into its neutral and individual atoms so take for example you have your your sodium your your we have you have your we have your elements that is bound to different molecules at the same time we have your atoms that are bound either to a protein to whatever molecule by your molecule on your solution your atomizer's job is actually to produce an individual and a neutral atom out of that and how do you do that that is through your atomizer and we actually have two types of atomizer we have your flame atomizer and we have your electrothermal atomizer which is your graphite furnace in your electrothermal atomizer you can actually hear it as well as the flameless atomic absorption spectrophotometry because it doesn't use your flame anymore but it uses your graphite furnace so let me explain to you what happened first so as i was mentioning a while back your atomizer is also your sample cell this is where your sample is being held while it is being measured in the system so your atomizer let's go first to your flame atomizer it can actually be of propane in nature okay your your flame atomizer can actually be a fuel gas it can actually be of propane in nature or acetylene with an oxidizing agent or a compressed gas which is burned to produce a flame so that is how your flame atomizer is okay so again coming from your nebulizer you spray your sample into your flame atom your flame atomizer for it to be atomized and at the same time for it to be held while it is being measured you also have your electrothermal atomizer and this is again in your flame less atomic absorption so we are using your graphite furnace so what we have here are actually graphite cylinder so from your nebulizer it your your sample will be held in your graphite cylinder in your graphite cylinder and eventually that graphite cylinder will be will be subjected to increasing temperature whereby your sample now will start to evaporize and as your sample start to evaporize it will now start to be um liberated from whatever molecule it is bound now forming an atomized sample okay an atomized sample so that's what happened between your flame atomizer and your electrothermal atomizer so the only difference that in your flame atomizer there is flame in your electrothermal atomizer there is no flame because you are using your graphite furnace again your graphite your graphite cylinder holds your sample and then your your temperature will be increased thereby evaporating the sample forming now your atoms okay so i hope we are clear so that is for your atomizer so again going back we did discuss your light source we did discuss your beamchaper your nebulizer your flame or your atomizer in general now we go to your monochromator and your photo detector we're actually nearing the end so your monochromator similarly to our spectrophotometer is the actually controls the light absorbed by the um by the sample so the light absorbed by the sample is impulses thus the light it emits is also impulses so it eyes the monochromator isolate the desired emission line from the other lump emission lines so it also has your entrance and exit slit so your monochromator in a nutshell um isolate a particular light coming from your sample that it will now be delivering to your photo detector again the photo detector we are using is your photo multiplier tube the most sensitive why here now here comes now the explanation we are using your photo multiplier tube because what we are measuring here in your aas are actually burst or pulses of light i want us to return to bullet number one of your monochromator again the light absorbed by the the sample are impulses how does it happen okay how does it happen the light coming from your your light source again is being chopped by your beam chopper producing now only pulses of light okay pulses of light and though those pulses of light are being absorbed by the sample in that very same manner okay so that your atoms are actually absorbing light by pulses and will also be emitting light by pulses so imagine that it is actually blinking or twinkling similar to your christmas light so the energy the light that it receives are impulses so the light that will it will also be emitting is also in the form of pulses okay sir maybe you are sir madame maybe you are wondering why is the policies so important i want you to remember this in your atomic absorption spectrophotometry there are two types of light and that is the light coming from your light source whether it is an electrode less or a hollow cathode lamp and of course when you are using your flame atomizer there is also light coming from your flame correct so those are two types of light so the question now is that how can we discriminate the light coming from your light source and the one that is just coming from my flame okay and what you want to measure is actually the light that is coming from your atoms that came from your light source so how do you do that what they did is actually to incorporate now your beam chopper so that is what the beam chopper does the beam chopper the beam chopper produces pulses of light therefore your atoms also absorb pulses of light ergo does it also be emitting pulses of light and those pulses of light will be the will be the only light to be detected by your monochromator in your photo detector and then the light coming from your flame will be electronically eliminated from the system so imagine that okay imagine that i want you to imagine that as we are actually going through okay so take for example this one your your samples are in this are in this part as you can see from the light source it's a continuous light but after passing through the the chopper it will now be in pulses represented by the broken light i hope you are following my my my laser so my laser pointer so it will now be in pulses so the atoms your analyte within that will also be absorbing the light by pulses okay it will now be absorbing the light by pulses so what we want is to this again what do we what do we want is to discriminate the light coming from the sample and the light coming from your flame so how do we do that okay the monochromator and your photo detector your photo multiplier tube are programmed only to detect and only to measure the pulsating light or the pulses coming from your atoms so in that case the light coming from your your flame or your burner will be electronically eliminated from the system so in that case you only will be able to measure the pulses of light therefore you will now be correctly measuring the concentration of your molecule okay so that's what your monochromator does there so in your photo detector again it's your photo multiplier tube okay one very good reason why the photo multiplier tube is that when you go back to the definition of photo multiplier tube it is actually very much sensitive because it can detect quick bursts of light in short or low intensity light and it is very important in the case of your atomic absorption spectrophotometry because again you are measuring pulses of light so in a nutshell in in in simpler terms your photo multiplier can detect quick bursts of light or quick pulses of light now coming from your sample or coming from your atoms that's why when it comes to photo detector in your aas we only talk about one and that is your photo multiplier tube okay so in a nutshell now that is your atomic absorption spectrophotometry you have your your atomic absorption spectrophotometry already you have your basic components and of course that is all about your atomic atomic absorption spectrophotometry we discussed the atomic absorption the components and of course the different function of those components within your atomic absorption spectrophotometry so i hope you did learn something new today and i hope i made myself clear so one thing that you i really need you to understand here are the pulses of light okay the pulses of light because that's very important so again your atomic absorption spectrophotometry measures the light absorbed by your atoms okay the light absorbed by your atoms so so to end this discussion let me leave you this quote from martin leuther king jr saying intelligence plus character that is the true goal of education so i hope you had a great time with me tonight so if you have questions so please do leave a comment in the comment section and if you have further questions just email me to my in my email so i am leaving it here so i am actually encouraging you to to leave comments down below so we will be discussing your questions on the comment in the discussion backs in the comment section and aside from that if you want me to make a video on i'll make to make a video a study video on how i will be studying your atomic absorption spectrophotometry please leave a comment down below and i will be doing a study guide a video while i am studying your aas and i will be sharing to you my techniques so without further i do thank you so much this has been jomar adams and i hope you did learn something new today so i would want to request everyone to please like this video share this video and please do subscribe to my channel again thank you so much and have a great day