Running Buffer composition in SDS Page - (Apr/11/2007 )

Hi everybody,

I need to prepare Running Buffer for SDS Page gel. I saw two buffers different in concentration (not in composition).
1-BufferA 5X: for 2 liter buffer 288 gr Glycine, 60 gr Tris-Base, 10 gr SDS.
2-BufferB 5X: for 2 liter buffer 144 gr Glycine, 30 gr Tris-Base, 10 gr SDS.

Does anyone know which one is the correct one (although I'm pretty sure both of them work well), and what will be the difference between them (only the cost??!!).

Thanks for your answers.

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I use the second one

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So do I

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we use solution 1 (we make a 10x solution).

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second one

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so you mean you use the recipie 1, but it is to prepare a 10x solution, and not a 5x solution like it is written?

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I used the first one too. But the SDS powder will be 20g instead.
I guess it is just the concentration difference. I presume it works at half of the concentration.

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According to the current protocol in molecular biology (vol2), for running normal SDS PAGE gel, the running buffer would be B (the 2nd one), and they call it 1x running buffer. Our lab also uses B.

However, also according to this book, for nonurea separation of peptides using SDS PAGE gel (could separate 5kD peptitide), then the running buffer would be 2x, i.e. similar to A, but SDS would be 20g instead. Of course, the making gel also got modified a little, mostly in concentration of various ingredients.

I guess both work OK. But why go for the expensive one if you don't have to.

Hope that help.

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