Used for quantitative determination of human norepinephrine levels in biological samples such as serum, plasma, or cell culture supernatants. Widely applied in clinical research and neuroscience studies to assess sympathetic nervous system activity. Helps in investigating conditions like hypertension, heart failure, stress-related disorders, and neurodegenerative diseases. Provides high sensitivity and specificity for accurate measurement of norepinephrine bound to tartaric acid, enabling reliable data in pharmacological and physiological experiments.