Antibody purification is a process in which antibodies are extracted from an antiserum which contains a mixture of compounds. Once purified, the antibodies can be used in a variety of ways. This process can be performed at labs which offer an antibody purification service, and people can also purify their own, if they have the necessary equipment and tools. This may be done in a lab where people want rapid turnarounds for their research, or when researchers are concerned about protecting the integrity of original research.
One of the major sources of antibodies is antiserum produced in animals. In this case, an animal is repeatedly injected with an antigen until it develops antibodies, and its blood is used to prepare an antiserum which can be purified to access the antibodies. Another source of antibodies is a cloned cell which produces antibodies as part of a colony of identical cells; this method is used for mass production of so-called “monoclonal antibodies.”
There are several techniques which can be used for antibody purification. The most suitable technique depends on the medium being purified. Antibodies made in eggs, for example, are treated differently than antiserum from a rabbit or goat. Affinity chromatography and protein A/G are both used in the pursuit of antibody purification, for the purpose of isolating antibodies from the rest of the solution. Classically antibody purification relies on using a substance which binds to a specific antibody, holding in place while the rest of the solution is washed away.
For research, relatively small amounts of antibodies may be needed. In other instances, they need to be generated in large amounts because they are being used in therapy or diagnosis. For example, antibodies can be used with an ELISA test to determine whether or not someone has been exposed to a virus. The test can reveal whether or not matching antibodies are present in the blood, and in what concentration, which can be important when determining the severity and extent of an infection. In this case, having ample supplies of antibodies on hand is necessary to avoid a lag time with testing.
Researchers can order custom antibodies through companies which produce antibodies. These companies often provide an entire package, supplying the researcher with purified antibodies at the end of a set period of time. The cost of antibody production and purification varies, depending on the company and the antibody being produced.