The apparatus used in gel electrophoresis primarily consists of a gel and an electrophoretic chamber.
Components of the Gel Electrophoresis Apparatus
Here's a breakdown of the key components, as described in the reference:
- The Gel: This serves as the medium through which molecules will move. Gels are typically made from:
- Agar: Often used for larger molecules, like DNA fragments.
- Polyacrylamide: Generally used for smaller molecules, like proteins.
- Electrophoretic Chamber: This is the housing for the gel and provides the electrical field necessary for the separation process. The chamber usually includes:
- A hard plastic box or tank that holds the gel and buffers.
- A cathode (negative terminal) located at one end.
- An anode (positive terminal) located at the opposite end.
How the Apparatus Works
The sample is loaded into wells in the gel, and an electric field is applied across the gel via the cathode and anode in the electrophoretic chamber. Molecules migrate through the gel based on their size and electrical charge, allowing for their separation. The electric current flows from the negative terminal to the positive terminal.
Practical Insights
- Buffer Solution: The electrophoretic chamber is filled with a buffer solution to ensure a stable pH and allow electrical current to flow.
- Power Supply: A power supply is used to generate the electric field needed for separation.
- Visualization: After separation, molecules often need to be visualized with dyes or special detection methods.
Example Application
Consider a DNA sample containing fragments of different sizes. When subjected to gel electrophoresis, smaller fragments will migrate more quickly towards the positive terminal, resulting in a separation based on size.
