Great Video! Love your channel! I have some minor corrections to your video: 1) TOF: detected m/z value is dependent on BOTH the molecular mass ("size") and the CHARGE of the analyte. it is not only dependent on the "size" as you stated. A peptide with a mass of 1 kDa, for instance, can be detected at ~ 1kDa m/z if it bears 1 charge, but also at 500 Da m/z if it bears 2 charges, and at 333 Da m/z if it bears 3 charges. 2) you should not use the term "size" when referring to the molecular mass of a molecule. These are 2 different physical properties. Thanks! :)
Great points! Thank you so much! I've been considering to make an updated version to this video since I could make a much nicer version today so when I do I'll make sure to include your corrections!👍
Thanks a million for this fantastic educational video. I have two suggestions, I guess it would be much better if you use some pictures from real instruments which are used in laboratories, and secondly, if you produce a series of videos on using the common analyser software to teach the whole PMF process, it would be great.
once you have "digested" the proteins and splitted them into parts of different molecular weights, how do you know which parts belong to the same protein in order to have an accurate identification of it?
This depends. Sometimes you do your best to isolate the protein as much as possible before you use MALDI-TOF. However, often you might compare the results to existing libraries of mass spectra in order to try and find a match. Does that help at all?
Excellent question! The MALDI part is ONLY responsible for ionizing the sample while the TOF is ONLY responsible for measuring the ionized sample. In other words, we can use another ionization method such as for instance electrospray ionization (ESI), which I cover in another video, instead of MALDI. In the same way, we can use another method instead of TOF to measure our sample. You can think of this as two different parts of one larger device that can be changed out depending on what samples you are measuring and so forth... First "real-life" metaphor that comes to mind would be in gaming, where you can either use a PC, Playstation or an Xbox and plug this device into a desktop screen, or some type of TV... Not the best analogy but hopefully that answers your question!
Hello this was a great video explaining how MALDI-TOF works! I am currently using the MALDI-TOF on some peptides I'm making and I had a question. The peptides we are making has a +4 net charge but on the maldi we usually see +1 charge mass (m/z) on the spectra and not the +4 charged (m/z) mass. Can you explain this? Thank you!
How does that show up exactly? I mean how do you know that you're seeing +1 charge rather than +4 charge?🤔 I've only analyzed things that had a +1 charge myself I'm afraid🙈😅
@@LucasLearnz Hi thanks for responding! I know that it is the +1 charge because that is the predicted mass of my peptide. My peptide has a mass of 1154 g/mol and that is the peak that I see on the maldi-tof. I am just confused because the peptide has charged amino acid residues that should be fully protonated with a net +4 charge when it is on the plate with the matrix.
Hi I'm currently trying to analyse both positive and negative MALDITOF spectra for some lanthanide complexes I synthesised to try and determine the molecular weight and hence structure of my products, but I'm really struggling to understand how to interpret the spectra. I would really appreciate any help you can offer.
Not entirely sure what you mean. Chemical Ionization is also an ionization technique true but they are different in terms of how they are carried out and how well they preserve the sample.
Please ask any questions you may have!
Can you please explain DESI technique?
Why is kinetic energy = electric potential in this concept ?
Great Video! Love your channel! I have some minor corrections to your video:
1) TOF: detected m/z value is dependent on BOTH the molecular mass ("size") and the CHARGE of the analyte. it is not only dependent on the "size" as you stated. A peptide with a mass of 1 kDa, for instance, can be detected at ~ 1kDa m/z if it bears 1 charge, but also at 500 Da m/z if it bears 2 charges, and at 333 Da m/z if it bears 3 charges.
2) you should not use the term "size" when referring to the molecular mass of a molecule. These are 2 different physical properties.
Thanks! :)
Great points! Thank you so much! I've been considering to make an updated version to this video since I could make a much nicer version today so when I do I'll make sure to include your corrections!👍
Thanks for the video! Very clear and simple explanation
Thank you so much for those nice words Octavio!😇
thx! it was very helpful for my presentation
I am happy to hear that!👍
Great explanation
Thankyou 🤟
Great that I could help!
Thanks a million for this fantastic educational video. I have two suggestions, I guess it would be much better if you use some pictures from real instruments which are used in laboratories, and secondly, if you produce a series of videos on using the common analyser software to teach the whole PMF process, it would be great.
Great suggestions! I'll see what I can do!
once you have "digested" the proteins and splitted them into parts of different molecular weights, how do you know which parts belong to the same protein in order to have an accurate identification of it?
This depends. Sometimes you do your best to isolate the protein as much as possible before you use MALDI-TOF.
However, often you might compare the results to existing libraries of mass spectra in order to try and find a match.
Does that help at all?
Very helpful! Thanks!
Excellent! Glad to hear it! I also have videos about MALDI and TOF separately if you wish to know more about either one of these two techniques😇👍
What exactly is the difference between MALDI-TOF and MALDI? Whitout measuring the TOF how does MALDI analyze the samples?
Excellent question! The MALDI part is ONLY responsible for ionizing the sample while the TOF is ONLY responsible for measuring the ionized sample.
In other words, we can use another ionization method such as for instance electrospray ionization (ESI), which I cover in another video, instead of MALDI. In the same way, we can use another method instead of TOF to measure our sample.
You can think of this as two different parts of one larger device that can be changed out depending on what samples you are measuring and so forth... First "real-life" metaphor that comes to mind would be in gaming, where you can either use a PC, Playstation or an Xbox and plug this device into a desktop screen, or some type of TV... Not the best analogy but hopefully that answers your question!
@@LucasLearnz perfectly explained, thank you very much!!
@@noraspeiser1865 Glad to hear that, thanks for commenting!!
Hello this was a great video explaining how MALDI-TOF works! I am currently using the MALDI-TOF on some peptides I'm making and I had a question. The peptides we are making has a +4 net charge but on the maldi we usually see +1 charge mass (m/z) on the spectra and not the +4 charged (m/z) mass. Can you explain this? Thank you!
How does that show up exactly? I mean how do you know that you're seeing +1 charge rather than +4 charge?🤔
I've only analyzed things that had a +1 charge myself I'm afraid🙈😅
@@LucasLearnz
Hi thanks for responding! I know that it is the +1 charge because that is the predicted mass of my peptide. My peptide has a mass of 1154 g/mol and that is the peak that I see on the maldi-tof. I am just confused because the peptide has charged amino acid residues that should be fully protonated with a net +4 charge when it is on the plate with the matrix.
THX!!!! Great explanation!
Happy I was able to help!
Thank you!!
Happy I could help!!😇👍
Thank you great video
Glad to hear that you found it helpful! Let me know if you have any questions or suggestions for other topics to cover!👍
Nice ❤
I'm happy you liked it!😇🙏
Make video on illumina sequencing
Here you go😇
ruclips.net/video/1kUNGeW-KKQ/видео.htmlsi=XdXbyBtO-CfHVxZj
Excellent teaching🎉Can you add a video on NMR spectroscopy?
A short video series on different aspects of NMR will be the next thing I do! Promise! :D
Hi I'm currently trying to analyse both positive and negative MALDITOF spectra for some lanthanide complexes I synthesised to try and determine the molecular weight and hence structure of my products, but I'm really struggling to understand how to interpret the spectra. I would really appreciate any help you can offer.
If you mail me some of the spectra at biotechlucas@gmail.com I can take a look😇👍
Also if you know what matrix you're using and the standard used for calibration that would help as well🙏
can you describe how to build one? thanks.
Interesting question! What is the context if I may ask?😇 Do you mean theoretically or how these are built by different companies?
So MALDI ionization technique is same as Chemical Ionization (CI) technique in GC mode?
Not entirely sure what you mean. Chemical Ionization is also an ionization technique true but they are different in terms of how they are carried out and how well they preserve the sample.
Thanks
Happy to help!😇
Can you go more in-depth about MALDI?
Absolutely, might do it this week or the next week at the latest!