ELISA kit is widely used in medical and biological research for detecting and quantifying substances such as peptides, proteins, antibodies, and hormones. It is commonly applied in disease diagnosis, including infectious diseases like HIV, hepatitis, and more recently, SARS-CoV-2. The kit enables high sensitivity and specificity in measuring analytes in complex biological samples such as serum, plasma, and cell culture supernatants. It is also used in quality control in pharmaceutical development, food testing for allergens, and environmental monitoring. Due to its adaptability and reliability, ELISA kits are standard tools in clinical laboratories and research settings.