Used for detecting and quantifying specific proteins, antibodies, or antigens in biological samples such as serum, plasma, cell lysates, and urine. Commonly applied in medical diagnostics to identify infectious diseases like HIV, hepatitis, and Lyme disease. Also used in research settings to measure cytokine levels, hormone concentrations, and biomarker discovery. Widely utilized in pharmaceutical development for monitoring immune responses during clinical trials. Offers high sensitivity and specificity, making it suitable for both qualitative and quantitative analysis in high-throughput screening environments.