A Review of SERS for Biomaterials Analysis Using Metal Nanoparticles

Surface enhanced Raman scattering (SERS) was first discovered in 1974 by an unexpected Raman signal increase from Pyridine adsorbed on rough Ag electrode surfaces by the M. Fleishmann group. M. Moskovits group suggested that this phenomenon could be caused by surface plasmon resonance (SPR), which is a collective oscillation of free electrons at the surface of metal nanostructures by an external light source. After about 40 years, the SERS study has attracted great attention as a biomolecule analysis technology, and more than 2500 new papers and 500 review papers related to SERS topic have been published each year in recently. The advantages of biomaterials analysis using SERS are as follows; 1 Molecular level analysis is possible based on unique fingerprint information of biomolecule, 2 There is no photo-bleaching effect of the Raman reporters, allowing long-term monitoring of biomaterials compared to fluorescence microscopy, 3 SERS peak bandwidth is approximately 10 to 100 times narrower than fluorescence emission from organic phosphor or quantum dot, resulting in higher analysis accuracy, 22) 4 Single excitation wavelength allows analysis of various biomaterials, 5 By utilizing near-infrared (NIR) SERSactivated nanostructures and NIR excitation lasers, auto-fluorescence noise in the visible wavelength range can be avoided from in vivo experiment and light damage in living cells can be minimized compared to visible lasers, 6 The weak Raman signal of the water molecule makes it easy to analyze biomaterials in aqueous solutions. For this reason, SERS is attracting attention as a next-generation non-invasive medical diagnostic device as well as substance analysis. In this review, the principles of SERS and various biomaterial analysis principles using SERS analysis will be introduced through recent research papers.