Coupling of Monoclonal Antibodies with Fluorophores

Immunofluorescence analysis has been greatly aided by the use of monoclonal antibodies (MAbs) modified by derivatization with fluorescent labels (1 ). Improvements of known fluorophores and development of new ones with a broader range of colors have paralleled the production of new detection systems with enhanced sensitivity, offering an increasingly more convenient alternative to radioactive probes (2 –8 ). When compared with radioisotopes, fluorescent dyes have the advantages of generally lower cost, ease of disposal, similar sensitivity, and the feasibility of multicolor labeling. The ability to use several colors (even five or more) allows one to identify multiple-cell subsets, or multiple structures or functions within a cell in the same experimental preparation (9 ). Progress in the production of MAbs and effective antigens obtained by conjugating small molecules, such as drugs and toxins, to proper carriers has enormously enhanced the prospects of using antibodies not only for diagnosing diseases, but also for detecting toxins or pesticides in foods and in the environment (10 ).