Stabilization of proteins

By the purification process, steps have to be taken to ensure in which the protein  of  interest  is  not  inactivated  or  denatured  either  through  physical  or  biological factors. The pH of the solutions used requires to be carefully buffered at a pH in that the protein is stable, commonly around pH 7. The temperature  frequently require to be maintained  below 25°C (generally  around  4°C) to avoid  thermal  denaturation  and  to minimize  the  activity  of proteases.  Ahead homogenization,   proteases  within  the  source  material  which  are  generally  in  a different subcellular  compartment  will be liberated into solution and come into contact  with the protein  of interest  and may degrade  it. For instance, the acid hydrolases in lysosomes could be liberated into solution and rapidly degrade the protein of interest. Although, as well as carrying out the process at low temperature,  protease inhibitors  are often involve in the buffers used  in  the  early  stages   of  the  isolation   process   in  order  to  minimize unwanted proteolysis.