Used in immunological research to quantify terminal complement complex (sC5b-9) levels in biological samples such as plasma, serum, or tissue extracts. Helps assess complement system activation, which is linked to inflammatory diseases, autoimmune disorders, and tissue damage. Commonly applied in studies of sepsis, lupus, age-related macular degeneration, and thrombotic conditions. Provides a reliable, sensitive method for monitoring disease progression and evaluating therapeutic interventions targeting the complement pathway.