Today, let's talk about the replacement of the buffer solution of the protein purification method. The following is introduced by the Suzhou protein purification system.
Although changing the buffer does not improve protein purity, it plays an extremely important role in protein purification protocols. Different protein purification methods require different pH and different ionic strength buffers. If you use ammonium sulfate to precipitate the protein, there is no doubt that the protein is in a high-salt environment, and you need to find a way to desalinate. The available methods include the use of semi-permeable membrane dialysis and the removal of salt by frequently changing the dialysis fluid. This method is acceptable. But it takes several hours, usually overnight, and it is difficult to use in large-scale purification.
The new type of equipment sandwiches the dialysis membrane between two plates, adding buffer on one side of the plate, and adding the protein solution to be desalted on the other side, and pressurizing the protein solution by a pump, which can make the solution on both sides for several hours. The internal balance is reached. If the pressure on the protein solution is increased, more water and salt can be forced into the dialysate through the dialysis membrane to achieve the purpose of protein concentration. There are also desalting columns on sale. The packing in the column is particles with a small pore size. Protein molecules cannot enter the pores, and the salt ions flow out of the column before the high concentration, so that the two are separated.
Each step of protein purification will cause the loss of the target protein, especially the step of buffer equilibration. The protein will bind to any surface it can contact, and shear forces, foaming, and rapid changes in ionic strength can easily inactivate the protein.
The above is the replacement of buffer for protein purification method. If you want to know more about Suzhou protein purification system, please pay attention to Suzhou Sepure Instrument Co., Ltd.!