SERS Analysis for Single-Molecule Detection of Disease Biomarkers

Surface-Enhanced Raman spectroscopy (SERS) is a powerful molecular vibrational fingerprinting technique that utilizes the enhanced electromagnetic fields produced by the excitation of localized surface plasmons from the nanostructures for the ultrasensitive detection of analytes down to a single molecule. The choice of substrates and noble metal nanostructures to engineer the hotspots plays a crucial role in realizing the single-molecule SERS analysis. This chapter summarizes the fundamental concepts and mechanisms behind SERS and the technological advancements in developing SERS substrates with patterned nanostructures. In addition, we highlight the application of this multidisciplinary approach in detecting the clinically significant biomarkers which are present at ultralow concentrations down to a single molecule for early disease diagnosis. Finally, we discuss the upcoming challenges and interesting insights of the single-molecule SERS technique for the real-time detection of biomolecules.