In order to fulfil their natural role in the body, antibodies are tailor-made to recognise specific structures on bacteria and viruses. They bind to these invaders and make them easier to destroy. However, it is possible to produce antibodies against many other substances. Their specificity makes them valuable laboratory reagents.The vast number of antibodies on the market reflects their wide range of application. Ways in which antibodies are used include:

• Antibodies tagged with fluorescent dye can be used to visualise a specific protein or structure within cells and tissues. When viewed under a fluorescent microscope, the antibodies appear in glowing colours. Differently coloured dyes enable several different structures to be highlighted simultaneously
• ELISA (enzyme-linked immunoassay) tests detect the presence or measure the amount of a substance in a sample. They use antibodies linked to an enzyme. The enzyme catalyses a biochemical reaction which results in a signal, for example, a change in colour. The quantity of test substance present is calculated from the strength of the signal. The home pregnancy test is an ELISA. When used to test urine, a colour change shows that the pregnancy hormone is present
• Western blot tests are used to investigate mixed proteins in a sample. The proteins are separated out by placing the sample on a gel through which an electric current is passed. Blotting paper is placed over the gel to pick up the separated proteins. Antibodies tagged with enzymes are used to stain the proteins to identify them
These three methods using antibodies are widely employed in every area of biological and medical research. The importance of antibody research is illustrated by the size of its contribution to biotechnology. Antibodies are at the heart of attempts to improve future treatment for health conditions. To help cope with this extraordinary demand, we at Novus Biologicals offer over 55,000 products in our antibody catalogue.