Very hard to know with such little detail. There could be a number of problems. Do your samples leak horizontally (into adjacent wells), vertically (down through the gel), diffuse randomly, between the gel and the casting cassette, etc etc? What is your gel recipe? Can you post a picture?

I completely agree with Grant that we need more information. Based on what you are saying I would guess 1) you are using the wrong size comb for the spacer plate (i.e. too small of comb for your plates such as 1.0 mm comb with 1.5 mm spacer plates or vice versa).or 2) you are not flushing your wells properly or at all. This can cause the sample to not fall into the well and "leak" into neighboring wells. On the other hand if you flush too rigorously, you can damage the well barrier and thus sample leaks into neighboring well. That's all I have no based on the information you provided.

Good luck,

~Adam

Dear Yogesh

There are several reseons:

1- Puncturing the well

2- Low polymerization of stacking gels

3- Warping of plate

Please tell me that all wells were leaking or some wells?

Also please check the pH of your samples.

Cheers

Good to know that this problem was resolves. In addition to the possible reasons above, in my experience gels stored at 4°C without adequate hydration are susceptible to shrinkage. Any shrinkage near the wells would result in detachment of the gel from the gel plates. Also samples left loaded in the wells without applying the electric current may eventually seep out!

Regards,

Anant

Dear Yogesh and hi everbody, 

I'm experiencing the very same problem you had some time ago. It happens sometimes that western blot samples leak out of the bottom of the wells and diffuse around in the stacking gel. Actually I think the samples diffuse between the stacking gel and the glass. Did you manage to fix the problem? I already tried to wash the glasses with EtOH 70% before casting the gels and I'm sure I'm not puncturing the well itself while loading the samples. I also take out the comb once the gels are in the electrophoresis box and covered with running buffer. Any idea is very welcome. thanks a lot. Marco

Hi everybody. I have the same problem too but with agarose gel (agarose powder and TAE buffer). The leaking was horizontal across the neighbouring well and sometimes below the gel. I have tried loading the samples (assuring the wells are not damaged) right after I cast the gel and let dry for almost 30 minutes, so does after leaving it for almost 5 hours. However, occasionally, I still have the same problem. Could it be because of the spacer of comb that I've expanded using masking tape or it is simply because it happens inevitably sometimes?

@Marco Morini.

I´ve done PAGEs thousands times so far, it never happend that the loaded sample was leaking horizontally into adjacent wells. Today was the first time and I could not figure out why. Did you already solve this problem?

I too faced the same problem. I changed my acrylamide solution and opened a new vial of APS. It's resolved.