Samples
The sample preparation is crucial in the case of the SDS-PAGE process. But to make it more simple, let's go through an example by which it will be easier.
"From the clinics, we got 4 samples from four different patients. We know that the disease for what we are looking is characterized by a high level of p53 for example. About the p53 we know that the molecular weight of the protein is exactly 53 kDa. We need to run the samples and detect it."
The crude sample from the patients contain hundreds of different sized and shaped proteins. In order to find our protein of interest, we need to cast a gel, which is capable to separate the proteins based on the size.
GEL CASTING
The basic component of the gel is acrylamide. This molecule is highly toxic, it is accumulating in the brain, thus the tissue damages slowly. The same molecule will appear in the oil that we are using for the fried dishes. Even more, we use the same oil even more acrylamide is generating. (Please do not use more than 2 times the same oil)
The gel has two separate parts the "bottom" and the "top" part.
The bottom part of the gel is the so-called separating gel. This is the bigger part of the whole structure, while the top is the sample collection gel. Every time we need to prepare two mixtures, one for the bottom and one for the top gels. In this mixture not only the acrylamide is there but also a buffer, a