SDS PAGE

Describe the purpose and process of SDS PAGE. (10 marks)


The purpose of the SDS PAGE is to separate proteins according to their size.
In order to prepare the SDS PAGE, we must firstly add the protein into the SDS using the pipette. The SDS solution is also known as Sodium dodecyl sulfate for its full name. Its function is to make the secondary or teritary structure of the protein to primary structure, and it becomes a linear strand. After putting into the SDS, the protein will be covered with many negative charges. The reason is because before it gets break down into primary structure, it has positive and negative charges. After soaking into the SDS, it becomes negative charges.
After the protein is being inserted into the well, the electric charges will flow through it by opening the switch. The proteins will flow from the negative electrode to the positive electrode. The reason is because the proteins have strong negativity, and it will therefore get attracted to the positive sides.
After some time, the proteins with different sizes will get stuck at the different locations, therefore we are able to determine the size of it, and telling which is larger and which is smaller.