The Spectrophotometer: A demo and practice experiment

The spectrophotometer is an instrument used to measure the effect of a sample on a beam of light. We can learn a lot about a substance by studying the way it interacts with light.
In this video, we'll demonstrate how to use a spectrophotometer to perform a basic experiment: determining the absorbance spectrum of red food coloring.
Included in the video is a short animation that illustrates the inner workings of a spectrophotometer.
Special thanks to Joe Issa and the Gaston College Biotechnology department for helping to make this video.
Practice using a virtual spec www.ncbionetwo...

[@wheresjohn1944]

very relaxing review before a lab practical

[@fariashinshin1041]

Exactly

[@thanushk]

Exactly

[@walsh0]

Exactly

[@randomdude4360]

Exactly

[@HiddenTalent_07]

Precisely

[@BrennanDemarest]

Excellent video. Clear cut and well filmed.

[@telracsazyl1243]

no cap. this channel goated

[@feminico2613]

bsmls 1b was here

[@achlys7290]

wala tayong ganto sa school scamm

[@vahidmirkhani]

6:07 What does this plot mean? What's our interpretation? As you can see, the absorbance is relatively high for wavelengths below 600, but 600 above is not absorbed and hence, transmitted. So the photons reaching your eyes from going through this solution, mostly have wavelengths between 600 and above and hence, the red color. I hope this helped a bit.

[@Teekay_ZA]

It helped a lot! Thank you

[@noork.631]

Thank u soo much

[@leventnergiz]

Thank you for your remarkable conclusion. it meant a lot to me.

[@amailyakter6589]

Thank you so much for such an effective demo, I got the idea of how to use this machine

[@athiramalukilikood6075]

Thankyou so much, today is my practical examination, and it was really really useful one😍

[@jamalfareedi996]

One of the best review of Spectrophotometer in lab

[@davidmonroy3965]

How do you determine the wavelength that should be used? can it be a constant, and keep it the same for all my samples?

[@darksector1389]

I'm assuming they are using a hydrogen source light where it has a constant wavelength when it enters the spectrometer. Then use this equation: d sin(theta) = m (lambda), where d = grating distance (which is written on device), m = 2 (using Balmer series for visible wavelengths). Then you get four discrete wavelengths of: 410 nm, 434 nm, 485 nm, 656 nm which are the spectrum of hydrogen emission.

[@theoryofeverything4237]

very nicely explained and the content is so smooth and crisp :)

[@binbinky78]

best explanation out there on how to use it. Thank you!

[@tinaishemachida9798]

could have never found a better explanation than this yohhhh!

[@A_NILAVIDILAUTAMI]

Hi, this is a very interesting video and easy to understand. I'm currently a second year pharmacy student, and I am learning about Spectrophotometer. Can I use this video for my college project? I'll give BioNetwork some credit or acknowledgement in my video. Thank you so much, stay safe and healthy!

[@NCBioNetwork]

Yes, you are welcome to use the video as part of your project. Please provide the appropriate reference / citation to this video. Thank you!

[@The_Bees_Knees93]

have a bio lab practical tomorrow, easily learned how to use it more by watching this video. thanks!!!! :)

[@ChadCarney-hu3du]

Now I have a way to measure if an increase/decrease of algae occurred in a sample of gymnodinium!

[@kusalseven3563]

Imagine working in a lab full of these retro style equipments 😌

[@토토로솔]

what is the purpose of using blank solution?

[@rrbuff1960]

I am not totally sure of your question here. The sample concentration is irrelevant for this activity. If you plot wavelength on x axis (380, 405, 430 nm....... ) versus the measured absorbance on the y axis you will find the wavelength of maximum absorbance, called lambda max. Each color has its own lambda max. That is the goal for this particular lab.

[@vinhluong3336]

Why does transmittance of a blank have to be adjusted to 100% before recording the transmittance (or absorbance) of sample at any wavelength?

[@NeuralManifolds]

At 2:07 what adjustment does the spectrophotometer makes inside when Transmittance is set to 100% while blanking ? what is behind that 100% transmittance knob?

[@dr.hebasabry1521]

Same question I need an explanation please

[@cophernicus510]

That intro music was fire 🔥

[@OluwatoyinAdelusi]

You just saved me from failing a bio lab practical! Thank you so much!! :D

[@telracsazyl1243]

@@bulletprooftrading its 8 bro

[@ibby_h5574]

@@telracsazyl1243 was 6 at the time he commented

[@Cosmicvisionz]

How can we calibrate spectrophotometer for lower concentrations of iron? Like in 1-5 PPb.

[@Naveenbabuborugadda]

What is the blank solution used here?

[@laraibfatima1643]

Sir I have a question ⁉️ 1.If you tell the transmitted light in %....then absorbed light must be in %......but you taught absorbed in (nm) and transmitted in % 2..if 10% is transmitted then 90% should be absorbed or used anywhere else?

[@thainguyen5553]

That's awesome! It would help me a lot for my experiment next week :D

[@oldboy4782]

Relaxing demonstration with fine video shot

[@TheViewer318]

Hye.. I have a question. If this is for adrenaline test in saliva, how could it help..? the output are all numbers on transmissions and absorbency. the aim to test the adrenaline is to detect stress, and through this test, how could it help? Thank u in advance.

[@infomatics315]

Can this be used for analysis of phosphorus content in plants

[@Dai_rui]

Hey are we increasing the wave length?

[@aurynhs196]

can you find starch concentration using uv spectrophotometer?

[@josephbenobasa]

This would come in handy for my lab tomorrow

[@anisarashid1135]

why it's adjusted to 100% T every time wavelength is changed?

[@RedGoddesscom]

Thank you for upload. The explanation how it works is very good!

[@woosungchoo3282]

lol why do you increse wavelenth by 25 each time just partice?

[@Mauberetl]

Can you tell me, what is the concentration of your samples, which you inserted into the sample compartment? I'm confused, varying wavelengths when you use?

[@jennifermiranda6998]

I was thinking the same thing. If the dilutions are made of the same solution, then why vary the wavelength? That and/or molar absorptivity should be the same, unless again, the samples are different. Also, no need to place the blank every time you run a sample made of the same solution (but only being diluted). Blank should be read again if you are running a different solution sample. Again, that's just me. I think they did these customizations for demonstration purposes.

[@serena3]

What will happen if you forget to wipe the cuvette before putting it in the spectrophotometer?

[@tamileditingstudios9325]

It will show wrong value.

[@gianpd1834]

someone know why they didn't make transmittance vs wavelengh tab?

[@mapalojohnchanda4107]

Absorbance spectrum for red food colouring

[@bennettegaper4344]

Thank you so much

[@charleskingsley4290]

This video was very helpful to me. Thank you so much for the video

[@celticbard9313]

Awesome job explaining this, thanks.

[@streaminggames9186]

nice video helped me to learn more

[@shyamkumar-cz5ow]

thats awesome! but i wanna know why are we changing wavelength of light for same samples?

[@crimsonwood5264]

To get a different absorbance values and use it to plot your graph because in each wavelength length the value of absorbance will change.

[@jiteshyadav3466]

Sir I want to check copper purity 99.99%. How to check this process.

[@rajput9s764]

Awesome and very useful😊😊

[@kiribundi]

Yes, if your concentration is higher, your absorbance will consequently be higher

[@eliyaskebede-v3v]

Very good story ❤❤🌹

[@nayanpanchal5538]

How we evaluate concentration

[@louisegabrielbotastas9583]

Bery helpul in our chemistry class

[@talibmuzafar8836]

how to calibrate the spectrophotometer?

[@Emotions_of_chemicals]

nice explanation...thanks bio network..

[@HiddenTalent_07]

Idk why I find this video so peaceful ahaha

[@temesgendeka4094]

Can you apload another video for polyvinyl alcohol

[@johnfernandes9004]

THANK YOU SO MUCH

[@kevingp12]

I have a practical too on monday!!!

[@atishkumar708]

purpose of blank?

[@chiomaobunadike3313]

I still don’t understand what we would do with these values

[@aashinabhatia1612]

What's the purpose of blank here

[@debjitmukherjee8494]

the video was very very helpful to me.,i request maintenance guide about the spectrometer video present it.

[@vincaalkaloids6732]

Thank you very much.

[@abdullahdar2527]

Even the man looks like Animated AI robot

[@snwbubble]

why so serious?

[@allroundergamer1738]

Thank you 🎈

[@peterluxus7382]

you don't this manually in 2019???

[@Sluo1947]

that was beautiful :')

[@raqiamalik9419]

hi, why you test the sample again can you reply me

[@RanaAyan-j6h]

To measure absorbance and transmission at different wavelength

[@jayeelli3906]

how to analyze an unknown substance using spectrophotometry?

[@ishanilahiri7387]

If you know what kind your unknown substance is like is it a protein or a reducing sugar, then prepare a standard curve of the substance (of known concentration) closest to your unknown substance, and then map it out.

[@jayeelli3906]

@@ishanilahiri7387 hi thank you. i love u so much

[@arbazkohati747]

tkanks for demo and practice exp

[@jordanmellis314]

Why did we have to set the wavelength to specifically 380 nm?

[@doooooms1586]

❤❤❤

[@munkhundarga9081]

VEry nice bro

[@zodd0001]

It takes a lot of time make just one complete spectrum. It must be an old version of spectrophotometer or just a didactic one.

[@fss1704]

zodd0001 fking yeah, i build an automatic spectrophotometer in my bedroom pretty much the size of a cigarette box that can connect to my cellphone via non standard bitbanged infrared signals using an adaptor in the audio jack to send commands to the spec microcontroller and receive the digital data via the jack microphone input, i spend 50usd in it and the result is pretty much high grade lab quality.

[@fss1704]

Theoretically you can do the read using an USB sound adaptor and bypass the input cap on the microphone, then use the sound output of a moving loudspeaker with a prism glued on top to filter the light, and a photodiode in the mic input to read the level of absorbance on each wavelenght.

[@sanofarnisha5899]

Thanks a lot

[@hezakadoo6514]

The soundtrack tho 👌

[@shahdragb9062]

well explained

[@nicolelevy219]

Excellent

[@bhartiandana8314]

It helps alot 👍

[@anannaone]

❤

[@deepakchoudhary9146]

Watching in online practical )

[@FeliciaAdedotun]

Very helpful....thanks

[@Mobashar61]

Nice❤

[@miklaszjay]

Looks like he knows what he's doing, but his data sheet is kinda sketchy. He's going to run into trouble when he's making the plot...

[@fss1704]

miklaszj non automatic spectrometer in 2018? You've gotta be kidding me, my DIY spectrometer cost $50 and does auto sampling directly to my cellphone screen, seriously, all of that user interaction and sample being completely taken in a different direction each time should make your results have a mount everest of error.

[@ethicalrevolution3294]

@@fss1704 What is your phone spectrometer like?

[@Zept41]

What song is this ? Dammmn

[@Mrsemanmahmoudm]

so good

[@Digital_Guidance]

Show calculation part

[@dailygrow6961]

Fascinating to see. Build one from paper on my channel 😂

[@pinkyy3]

Me too!! Ahhhh :S good luck!!

[@yxz458]

u don't have to set the transmittance to zero before putting in the blank, since the trans/abs will be changed to either 0 or 100 after putting in the blank solution. this extra step is confusing and unnecessary...

[@fss1704]

Joanna Zhang i made a diy version for 50usd and it can plot the results in the screen of my cellphone, and it's a LOT more precise than this "remove x and exchange it by z" error monstruosity. Good fking luck correlating all of this data points from a moving sample.

[@alvinlisyandi8541]

Ilmunya sangat bermanfaat tapi sayang saya tidak bisa bahasa Inggris

[@tremainewheatley471]

「コンテンツを調整する必要があります」、

[@ボンズ-i6k]

0:16

[@crazyexpriementknig543]

Bisleri Water ke jitne bhi test hai Jaise ki Sulfate /Nitrate /iron/Hardness/Calcium etc. Sabhi test Hindi Language me bhejo. Please.

[@Mauberetl]

nice..

[@t.s.m7116]

استمر حبي

[@ulfataabid2809]

I have a qstion sir .. can u please help me sir ..... Make a report about Spectrophotomter from zero to 100... I don't know sir what I write in this assignment .... Becz of covid I never seen this practical .... How can I write .. can u plz help me sir so I can learn something about this and I can submit my assignment... Waiting for ur rply sir

[@joshuaronisjr]

I don't know about that data though...

[@oldboy4782]

I almost gonna sleep

[@indrarayendra5530]

Dewissengi aga kasi bettuanna

[@sdlmalkapurbuldana2175]

PLEASE SEND ME SAME PROCEDURE FOR WATER FLUORIDE

[@رنيمالديرية]

جميل