Practice question

In SPR terminology, ligand denotes macromolecule covalently immobilized to sensor chip dextran via amine coupling, while analyte is soluble binding partner in mobile phase. During association phase, analyte solution is injected at constant flow over ligand surface, allowing complex formation monitored as increase in resonance units. After injection, buffer flow induces dissociation. This orientation distinguishes immobilized state from flowing state. Detection is optical plasmon shift, not ELISA enzymatic reaction, and analyte is never immobilized or used for coating in conventional setup.