Isoelectric point calculations are critical in your biochemistry course and MCAT prep. The isoelectric point or pI gives you the pH at which the molecule has a net zero charge. This comes from a balance of protonation and deprotonation so that all positive and negative charges cancel out.
This video shows you how to calculate amino acid isoelectric point along with a shortcut to help you figure out WHICH pKa to use when given a side chain pKa value.
(Watch on YouTube: Isoelectric Point of Amino Acids. Click cc on the bottom right for video transcript)
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This is video 6 in the Amino Acids Series. Click for complete series + Practice Quiz and Cheat Sheet
Have you grabbed the FREE Printable Cheat Sheet to follow along? CLICK HERE
No one… I repeat no one can explain this like you! I have your voice in my head as I study these lol!
This is the most amazing video I’ve ever learned from. Some prep companies failed to explain this fully like you did, and I found myself making the mistakes you mentioned! This is great, wish I found it a bit earlier.
Rim, I’m glad this has been helpful to you! I was a student once too, so I know exactly what you mean. I try to provide the resources I wish I could have had. How long until you have your MCAT exam?