What is the function of the Wash Buffer in the chromatography process?

The function of the Wash Buffer in the chromatography process is primarily to wash away less hydrophobic proteins.

During chromatography, particularly in affinity chromatography where GFP is being purified, the matrix is designed to bind to specific proteins based on their properties. The Wash Buffer is strategically used to remove non-specifically bound or less strongly interacting proteins that do not have a high affinity for the target protein, in this case, GFP. By carefully selecting the composition of the Wash Buffer, you can ensure that it is effective at washing away unwanted contaminants while keeping the target protein bound to the matrix.

This ensures that when you proceed to the elution step, the only proteins present are those that have a strong affinity for the column, which results in a more purified product. Thus, the role of the Wash Buffer is critical in helping to refine the purification process by selectively removing undesired proteins without affecting the more tightly bound target proteins.