Antibodies are highly specific proteins produced by the immune system and are widely used in fields such as medicine, life sciences and biotechnology. Antibody separation and purification is the process of obtaining a single specific antibody from a complex mixture. Here are several main antibody separation and purification methods:
Antibody purification
1. Affinity chromatography : This method utilizes the specific binding between the antibody and its corresponding antigen to purify the target antibody. The antigen is usually immobilized on a solid phase, and then a mixed antibody sample is added. The antibody binds to the antigen and attaches to the solid phase, while other non-specific components are removed through washing steps. Finally, the target antibody is eluted from the solid phase under appropriate conditions.
2. Ion exchange chromatography: This method is based on the difference in the charge state between different antibodies. It uses an ionic matrix to fix these antibodies and uses buffers with gradient concentrations to make the antibodies adsorb/elute according to the method for separation and purification. Specifically, according to the charge properties of the antibody, select an appropriate ionic immobilization matrix (such as DEAE, CM, etc.), pass the mixed antibody sample through the matrix under the adjustment of the pH value of the buffer, and then elute the target antibody through a gradient.
Antibody preparation
3. Gel filtration method: This method uses molecular weight differences to purify the target antibody. In the gel layer, the antibody samples are further separated based on their different molecular weights. Usually, a gel filtration column with appropriate parameters such as molecular weight and pore size is selected, and the target antibody can be purified and purified efficiently through washing.
4. Dialysis method: This method is based on the size difference of antibody molecules and uses a semipermeable membrane to dialyze and purify the mixed sample. A dialysis bag is used to place the mixed sample inside, and then the buffer is used for dialysis. According to the molecular weight of the antibody, the antibody is separated after dialysis.
Antibody separation
There are many other separation and purification methods that can also be used for antibody separation, such as hydrophilic exchange chromatography, hydrophobic exchange chromatography and affinity adsorption. It is necessary to choose the most suitable method for purification based on the specific requirements of the experiment and the characteristics of the antibody.