Enzyme-Linked Immunosorbent Assay (ELISA)
Introduction to ELISA Enzyme-Linked Immunosorbent Assay (ELISA) is a powerful biochemical technique used to detect the presence and quantify the concentration of antigens (proteins, peptides, hormones, etc.) or antibodies in a sample. ELISA is widely utilized in clinical diagnostics, research, and quality control due to its high sensitivity, specificity, and ease of use. Principles of ELISA The fundamental principle of ELISA involves the specific binding of an antibody to its corresponding antigen, which is then detected by an enzyme-linked antibody capable of producing a measurable signal, usually a color change, upon addition of a substrate. The intensity of the signal is directly proportional to the amount of antigen or antibody present in the sample. Types of ELISA ELISA can be broadly categorized into four main types based on the format and the way the antigen or antibody is detected: 1. Direct ELISA: - Principle: In direct ELISA, the antigen is immobilized on the microplate, a