Noble metal gold (Au) and silver (Ag) nanoparticles (NPs) are used to conjugate with M3 peptides. The AuNPs-sGFP and AuNPs-M3 peptide forms an active SERS hot spot through self-assembly and GFP complementation. The nanoparticles self-assemble into surface-enhanced Raman-scattering (SERS) nanoclusters. The nanocluster can be a contrast agent for multimodal SERS and photoacoustic microscopy with single-cell sensitivity.
Reference: M3 peptide was purchased from LifeTein.
Cellular imaging by targeted assembly of hot-spot SERS and photoacoustic nanoprobes using split-fluorescent protein scaffolds
https://www.nature.com/articles/s41467-018-03046-w