Surface Plasmon Resonance (SPR): Utilizes the unique optical properties of metallic nanoparticles to detect biomolecular interactions in real-time. Fluorescence Resonance Energy Transfer (FRET): Uses energy transfer between quantum dots and fluorophores to detect biomarker presence. Electrochemical Sensors: Employ nanomaterials to enhance the sensitivity of electrochemical detection methods. Magnetic Immunoassays: Utilize magnetic nanoparticles for highly sensitive detection of biomarkers through magnetic separation techniques.