Assay technology refers to a set of methods and techniques used to measure the presence, amount, or activity of a substance, often in biological samples. This technology is crucial in fields like pharmaceutical research, clinical diagnostics, and environmental monitoring, where accurate measurements are essential for understanding health and safety. Common types of assays include enzyme-linked immunosorbent assays (ELISA), polymerase chain reaction (PCR), and mass spectrometry. Each method has its own specific applications and advantages, allowing researchers and clinicians to detect diseases, monitor treatment responses, and analyze complex mixtures effectively.