Gel electrophoresis

[sam0001]

 Following amino acids are separated using gel electrophoresis at a low pH. Starting from the negative terminal, to the positive terminal, what is he order of amino acids?

Alanine, Argonne, aspartic acid, cystenine and glutamic acid.


I'm not sure which is more important, weight or charge?

[thushan]

Charge I think would definitely be more important...

well, that would make more sense anyway. Mao to confirm.

[sam0001]

I'm confused as to whether glutamic acid will migrate further than serene at a low pH. It's got a greater charge, but it's also the larger molecule.

[Mao]

Charge and mass are both important. Separation by charge is always there, separation by mass depends on what gel matrix is used.

For DNA gel electrophoresis, each fragment can contain a few thousand base pairs, and we can use a rather coarse gel matrix (reasonably large pores) to separate by mass, a bit like how column chromatography works.

For protein gel electrophoresis, I'm not certain what gel they use, but the same thing should happen if we choose the right gel with small enough pores. Though more commonly, we use a method called 'zone electrophoresis' (not part of vce).

If I had to guess, I will say distance travelled is proportional to

[Nobby]

If I had to guess, I will say distance travelled is proportional to

Similar to mass spec?

[Mao]

If I had to guess, I will say distance travelled is proportional to

Similar to mass spec?

Inverse of mass spec, but roughly the same idea.

I can't promise it's a linear proportionality, but it'll definitely play an important factor. This kind of chemistry is always a bit iffy, there's no simple way to decide what's important in the formula and what's not.