Figure 15.5 — Surface enhanced Raman scattering (SERS) Figure 15.5 — Surface enhanced Raman scattering (SERS). SERS of bovine serum albumin (BSA) proteins performed in liquid by optically trapping gold colloidal aggregates on which the protein is adsorbed. The enhanced BSA peaks are indicated: SS, disulfide bridges; Tyr, tyrosine; Trp, tryptophan, amide bands, stretching modes. The asterisks indicate the SERS signal from pyridine.Reprinted with permission from Messina et al., J. Phys. Chem. C 115, 5115–22. Copyright (2011) American Chemical Society.