Protein quantification is divided into “total quantification method” of whole protein and “individual quantification method” of specific protein according to its purpose. It is an indispensable part of biological experiments. In order to verify the success of cell lysis, or to compare or standardize multiple samples for parallel experiments, protein cytolysis should be performed for protein quantification; in order to determine protein yield, the purified protein should be quantified; In order to label the purified protein with biotin or reporter enzyme, the protein sample should also be quantified to ensure that the labeling reaction is carried out at the appropriate chemical concentration.