Electrophoresis orgo question

[pbure9]

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So here's a pretty interesting question I found in kaplan.
I thought I had this stuff down but I'm a little confused.

The question read as follows... A non polar amino acid has a pHi of 7.5 (so its neutral state)... when subjected to electrophoresis at pH 12, this amino acid will:

- migrate to the cathode
- migrate to the anode

So my logic. At pH of 12, its basic because it has an NH2 group and a COO-. So it would move towards the positive electrode, which I always had thought was the cathode. But the answer is anode? I then read online that in electrophoresis is an electrolytic cell where the anode is the + electrode. But don't electrons still go from anode to cathode in an electrolytic cell.
Anyway, hope you guys can help out. Thanks

 

[iwannabadentist]

R-O-C-A
Reduction ALWAYS occurs at the Cathode
Oxidation ALWAYS occurs at the Anode

Those are the only 2 constants in electrochemical cells. Other then that, in a Galvanic cell, anode is the negative end and cathode is the positive end - which is "normal" because the reactions in a galvanic cell are spontaneous. In an Electrolytic cell, this is "switched" meaning that the anode becomes the positive end and the cathode is the negative end - this is because the reactions are non-spontaneous. Hope that makes some sense?!

 

[tdkyun]

In electrophoresis there is an external source of power so like iwannabadentist has mentioned ends are switched.

 

[toothytay]

Yeah!! iwannabadentist has it down.

Here's what I always remember:

REDuction CAThode
ANode OXidation

My Gen chem prof drilled that into my head! red cat...an ox!

Then Kaplan said this...

Anions migrate to Anode
Cations migrate to Cathode

Best of luck!

 

[little joe bug]

It really makes no difference here what kind of cell we are talking about. At a ph of 12 an amino acid is always negative and thus it is an anion and anions always migrate to the anode!!