Used in immunological research to quantify complement fragment C3a levels in biological samples such as serum, plasma, or tissue homogenates. Enables assessment of complement system activation, which is critical in studying inflammatory diseases, autoimmune disorders, and immune responses to infection. Commonly applied in preclinical studies, biomarker validation, and drug development where modulation of the complement pathway is a target. Provides a reliable, sensitive, and specific method for measuring C3a concentration, supporting research into conditions like sepsis, asthma, neurodegenerative diseases, and ischemia-reperfusion injury.