Used in laboratories to detect and measure specific proteins, antibodies, or antigens in biological samples such as blood or serum. Commonly applied in medical diagnostics to identify infectious diseases like HIV, hepatitis, and Lyme disease. Also used in research settings to study immune responses, hormone levels, and biomarkers. Provides a sensitive and high-throughput method for analyzing multiple samples quickly. Widely used in clinical testing, pharmaceutical development, and quality control in biotechnology.