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Western Blot on an IEF separated recombinant protein - (Sep/22/2006 )

Hi everyone!
I tried to blot proteins from IEF gel, which I cast my own to PVDF membrane. But, I failed to detect any bands on the film. I transfer the gel with tris, glycine and methanol buffer...Am i using the wrong buffer?? :huh: :(

TQ

Spling spling

-spling-

what do you mean by "IEF gel"? is it a native PAGE slab gel or tube gel? analytic or even preparative IEF is commonly performed with IEF acrylamid gel fixed on plastic strips; because of the plastic on one side they cannot be blotted; your transfer buffer system should contain SDS; anyway, your "IEF gel" should be soaked in your SDS-containing transfer buffer before blotting

-The Bearer-

Thanks for your reply Kosmodrom..
U are rite, there is always a plastic strips attached to one side of IEF acrylamide gel..but I prepare myself using Biorad electrophoresis unit (mini protean III) which used to run SDS-PAGE. Therefore, blotting was performed w/o plastic. But, I never add SDS in transfer buffer,so I agree with you that should add SDS in the buffer to re-charge the proteins. Do you have any idea what's the concentration of SDS in buffer??

tongue.gif tongue.gif

-spling-

My transfer buffer is made of 100 mL methanol, 100 mL premade buffer TGS from biorad (composed of 25mM tris, 192 mM glycine, 0,1% w/v SDS, pH 8,3) and bring up to 1 L with distilled water. It has always worked fine.
Hope this helps smile.gif

-pumuki-

QUOTE (pumuki @ Sep 25 2006, 04:36 PM)
My transfer buffer is made of 100 mL methanol, 100 mL premade buffer TGS from biorad (composed of 25mM tris, 192 mM glycine, 0,1% w/v SDS, pH 8,3) and bring up to 1 L with distilled water. It has always worked fine.
Hope this helps smile.gif



Thanks Pumuki!!!

I will give a try !

biggrin.gif tongue.gif

-spling-

for SDS-gels we use a self-mixed transfer buffer modified and adapted from Towbin et al., PNAS (1979), containing 48 mM Tris, 30 mM Glycin, 0.037 % (w/v) SDS, 20 % methanol;

however, samples were boiled in 5 % SDS, and in running buffer is about 1.25 % SDS; soaking your native gel in original Towbin-buffer will not contain enough SDS; therefore, add 5 % SDS in an aliquot of transfer buffer for only some minutes to incubate the gel immediately after PAGE ( years ago I´ve done a similar experiment and incubated too long: smaller polypeptides were washed out of the gel!); wash than quickly in a transfer buffer aliquot of 1.25 - 2% SDS; this last mentioned buffer should also be used for transfer; use cooled tank blotting for several hours

-The Bearer-